# 代码审查报告 **文件:** `data\demo-pmd\src\com\demo\designep\DesignErrorProne.java` **语言:** java **耗时:** 195.1s **分析工具:** pmd --- 总计: 771 | 错误: 166 | 警告: 598 | 建议: 7 静态分析 · 762 个问题 - 🔴 `pmd:AbstractClassWithoutAnyMethod` L30 抽象类没有抽象方法，abstract 可能只是用来阻止实例化 建议: 如果目的是阻止实例化，应使用私有或 protected 构造函数而非 abstract。 - 🔴 `pmd:SystemPrintln` L39 使用了 System.out/err 输出 建议: 改用 SLF4J/Log4j 等日志框架记录输出。 - 🔴 `pmd:AvoidThrowingNullPointerException` L75 避免手动抛出 NullPointerException 建议: 应通过参数校验、Objects.requireNonNull 等方式处理，而不是直接 new NullPointerException。 - 🔴 `pmd:AvoidThrowingRawExceptionTypes` L82 避免抛出原始异常类型 RuntimeException 建议: 抛出自定义异常或更具体的异常类型，并携带业务上下文。 - 🔴 `pmd:ClassWithOnlyPrivateConstructorsShouldBeFinal` L93 只有私有构造函数，应声明为 final 建议: 给类添加 final 修饰符，防止通过反射或内部类扩展。 - 🔴 `pmd:SystemPrintln` L103 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L140 Usage of System.out/err - 🔴 `pmd:FieldNamingConventions` L149 字段命名不符合约定 建议: 按 Java 命名规范：常量用 UPPER_SNAKE，普通字段用 lowerCamel。 - 🔴 `pmd:SystemPrintln` L155 Usage of System.out/err - 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🔴 `pmd:SystemPrintln` L430 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L431 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L432 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L433 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L436 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L437 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L438 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L439 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L440 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L441 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L442 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L443 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L444 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L445 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L446 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L447 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L450 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L451 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L452 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L453 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L454 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L455 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L456 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L457 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L458 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L459 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L460 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L461 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L464 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L495 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L496 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L497 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L498 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L501 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L502 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L503 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L504 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L507 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L508 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L509 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L510 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L513 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L514 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L515 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L516 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L528 Usage of System.out/err - 🔴 `pmd:AvoidReassigningParameters` L538 避免重新为参数赋值 建议: 使用新的局部变量保存修改后的值。 - 🔴 `pmd:SystemPrintln` L539 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L577 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L578 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L586 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L597 Usage of System.out/err - 🔴 `pmd:ConstructorCallsOverridableMethod` L693 构造函数中调用了可重写方法 建议: 避免在构造期间调用非 final/method，或将该方法设为 final/private。 - 🔴 `pmd:DoNotCallGarbageCollectionExplicitly` L702 不要显式触发垃圾回收 建议: 删除 System.gc()，交由 JVM 自动管理内存。 - 🔴 `pmd:AvoidThrowingRawExceptionTypes` L728 Avoid throwing raw exception type RuntimeException. - 🔴 `pmd:EqualsNull` L758 避免使用 equals() 与 null 比较 建议: 使用 o == null 判空，而不是 o.equals(null)。 - 🔴 `pmd:AvoidReassigningParameters` L766 Avoid reassigning parameters such as 's' - 🔴 `pmd:SystemPrintln` L768 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L788 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L790 Usage of System.out/err - 🔴 `pmd:MethodNamingConventions` L816 方法命名不符合约定 建议: 使用 lowerCamelCase 命名方法，如 sameName()。 - 🔴 `pmd:ClassWithOnlyPrivateConstructorsShouldBeFinal` L829 This class has only private constructors and may be final - 🔴 `pmd:MoreThanOneLogger` L835 类中包含多个 logger 建议: 统一使用一个 logger 实例，避免日志输出混乱。 - 🔴 `pmd:SystemPrintln` L843 Usage of System.out/err - 🔴 `pmd:ReturnEmptyCollectionRatherThanNull` L882 应返回空集合而不是 null 建议: 返回 Collections.emptyList() 或 List.of()。 - 🔴 `pmd:SuspiciousEqualsMethodName` L909 方法名与 equals(Object) 高度相似，容易误导 建议: 重命名方法，或改为真正重写 equals(Object)。 - 🔴 `pmd:SystemPrintln` L928 Usage of System.out/err - 🔴 `pmd:FieldNamingConventions` L996 The field name 'TypeName' doesn't match '[a-z][a-zA-Z0-9]*' - 🔴 `pmd:SingleMethodSingleton` L1029 类包含多个 getInstance 方法，单例模式混乱 建议: 只保留一个无参 getInstance()，移除重载方法。 - 🔴 `pmd:ClassWithOnlyPrivateConstructorsShouldBeFinal` L1029 This class has only private constructors and may be final - 🔴 `pmd:SingletonClassReturningNewInstance` L1039 getInstance 总是创建新对象，不符合单例行为 建议: getInstance 应返回缓存的唯一实例，而不是新建对象。 - 🔴 `pmd:SystemPrintln` L1070 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L1078 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L1089 Usage of System.out/err - 🔴 `pmd:FieldNamingConventions` L1096 The constant name '_LOG' doesn't match '[A-Z][A-Z_0-9]*' - 🔴 `pmd:GuardLogStatement` L1101 日志调用应使用日志级别守卫包裹 建议: 添加 if (LOGGER.isDebugEnabled()) 等守卫，或使用占位符避免字符串拼接。 - 🔴 `pmd:SystemPrintln` L1134 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L1178 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L1208 Usage of System.out/err - 🔴 `pmd:SystemPrintln` L1218 Usage of System.out/err - 🔴 `pmd:AvoidBranchingStatementAsLastInLoop` L1222 避免在循环末尾使用 break/continue 作为最后一条语句 建议: 调整循环结构，使正常退出条件更明确。 - 🔴 `pmd:AvoidMultipleUnaryOperators` L1230 多个一元运算符叠用可能造成误解或 bug 建议: 简化表达式，只保留一个运算符或使用括号明确语义。 - 🔴 `pmd:AvoidMultipleUnaryOperators` L1231 Using multiple unary operators may be a bug, and/or is confusing. - 🔴 `pmd:SystemPrintln` L1232 Usage of System.out/err - 🔴 `pmd:BrokenNullCheck` L1239 null 检查逻辑有误，可能导致 NullPointerException 或逻辑错误 建议: 检查短路语义：判空应使用 && 或 || 正确组合，并在空值分支避免解引用。 - 🔴 `pmd:BrokenNullCheck` L1242 Dereferencing the qualifier of this expression will throw a NullPointerException - 🔴 `pmd:ProperCloneImplementation` L1254 clone() 应通过 super.clone() 实现 建议: 使用 super.clone() 并强制转换返回类型，而不是 new 新对象。 - 🔴 `pmd:ProperCloneImplementation` L1286 Object clone() should be implemented with super.clone() - 🔴 `pmd:FieldNamingConventions` L1339 The field name 'LOG' doesn't match '[a-z][a-zA-Z0-9]*' - 🔴 `pmd:FieldNamingConventions` L1344 The constant name '_LOG' doesn't match '[A-Z][A-Z_0-9]*' - 🔴 `pmd:ClassWithOnlyPrivateConstructorsShouldBeFinal` L1372 This class has only private constructors and may be final - 🔴 `pmd:FieldNamingConventions` L1373 The static field name 'INSTANCE' doesn't match '[a-z][a-zA-Z0-9]*' - 🔴 `pmd:ClassWithOnlyPrivateConstructorsShouldBeFinal` L1384 This class has only private constructors and may be final - 🔴 `pmd:FieldNamingConventions` L1385 The static field name 'INSTANCE' doesn't match '[a-z][a-zA-Z0-9]*' - 🔴 `pmd:SystemPrintln` L1400 Usage of System.out/err - 🟡 `pmd:AtLeastOneConstructor` L30 每个类应至少声明一个构造函数（适用于所有命中项） 建议: 为没有构造函数的类添加显式构造函数；若类不应被实例化，则改为私有构造。 - 🟡 `pmd:AbstractClassWithoutAbstractMethod` L30 该抽象类没有任何抽象方法 建议: 删除 abstract 关键字，或为类增加抽象方法。 - 🟡 `pmd:AtLeastOneConstructor` L34 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L35 缺少默认访问修饰符的注释（方法/字段/类） 建议: 为包级私有成员添加 /* default */ 注释，或显式声明 private/protected/public。 - 🟡 `pmd:MethodArgumentCouldBeFinal` L35 参数未被赋值，可以声明为 final（适用于所有命中项） 建议: 在方法参数前添加 final 修饰符，避免无意中重新赋值。 - 🟡 `pmd:MethodArgumentCouldBeFinal` L35 Parameter 'b' is not assigned and could be declared final - 🟡 `pmd:MethodArgumentCouldBeFinal` L35 Parameter 'c' is not assigned and could be declared final - 🟡 `pmd:CollapsibleIfStatements` L37 该 if 语句可以与父级 if 合并 建议: 使用 && 或 || 将嵌套条件合并，减少嵌套层级。 - 🟡 `pmd:AvoidDeeplyNestedIfStmts` L38 if 嵌套过深，难以阅读 建议: 使用卫语句、提前返回或提取方法降低嵌套深度。 - 🟡 `pmd:CollapsibleIfStatements` L38 This if statement could be combined with its parent - 🟡 `pmd:AtLeastOneConstructor` L47 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L48 Missing commented default access modifier on method 'bad()' - 🟡 `pmd:AvoidRethrowingException` L51 捕获异常后仅重新抛出，应避免 建议: 不要捕获该异常，直接在方法签名中声明抛出；若必须捕获，请加入实际处理逻辑。 - 🟡 `pmd:CommentDefaultAccessModifier` L55 Missing commented default access modifier on method 'doWork()' - 🟡 `pmd:AtLeastOneConstructor` L60 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L61 Missing commented default access modifier on method 'bad()' - 🟡 `pmd:CommentDefaultAccessModifier` L68 Missing commented default access modifier on method 'doWork()' - 🟡 `pmd:AtLeastOneConstructor` L73 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L74 Missing commented default access modifier on method 'bad()' - 🟡 `pmd:AtLeastOneConstructor` L80 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L81 Missing commented default access modifier on method 'bad()' - 🟡 `pmd:AtLeastOneConstructor` L87 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L88 Missing commented default access modifier on method 'bad()' - 🟡 `pmd:AvoidUncheckedExceptionsInSignatures` L88 方法/构造函数不应显式声明非受检异常 RuntimeException 建议: 从 throws 子句中删除非受检异常。 - 🟡 `pmd:MissingStaticMethodInNonInstantiatableClass` L93 类无法实例化，且没有提供任何静态方法或字段 建议: 添加 public static 方法/工厂方法，或将类声明为 final 并仅作工具类使用。 - 🟡 `pmd:AtLeastOneConstructor` L99 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L100 Missing commented default access modifier on method 'bad(int, int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L100 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:MethodArgumentCouldBeFinal` L100 Parameter 'b' is not assigned and could be declared final - 🟡 `pmd:CollapsibleIfStatements` L102 This if statement could be combined with its parent - 🟡 `pmd:AtLeastOneConstructor` L110 Each class should declare at least one constructor - 🟡 `pmd:DataClass` L110 类疑似数据类（只包含 getter/setter） 建议: 将数据与行为封装在一起，增加业务方法，避免仅作为数据容器。 - 🟡 `pmd:PublicMemberInNonPublicType` L113 非公共类型中声明了公共成员 建议: 将类改为 public，或将该成员的访问级别降为 package 私有。 - 🟡 `pmd:PublicMemberInNonPublicType` L116 Public member 'setName' declared in a non-public type - 🟡 `pmd:MethodArgumentCouldBeFinal` L116 Parameter 'name' is not assigned and could be declared final - 🟡 `pmd:PublicMemberInNonPublicType` L119 Public member 'getAge' declared in a non-public type - 🟡 `pmd:PublicMemberInNonPublicType` L122 Public member 'setAge' declared in a non-public type - 🟡 `pmd:MethodArgumentCouldBeFinal` L122 Parameter 'age' is not assigned and could be declared final - 🟡 `pmd:MissingSerialVersionUID` L128 实现 Serializable 的类应定义 serialVersionUID 建议: 添加 private static final long serialVersionUID = 1L; - 🟡 `pmd:AtLeastOneConstructor` L128 Each class should declare at least one constructor - 🟡 `pmd:DoNotExtendJavaLangError` L128 异常不应继承 java.lang.Error 建议: 应继承 Exception/RuntimeException，Error 留给 JVM 内部严重错误。 - 🟡 `pmd:AtLeastOneConstructor` L132 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L133 Missing commented default access modifier on method 'bad()' - 🟡 `pmd:UnusedAssignment` L134 变量的初始值从未被使用 建议: 删除初始赋值，或直接使用最终需要的值初始化。 - 🟡 `pmd:CommentDefaultAccessModifier` L142 Missing commented default access modifier on method 'check()' - 🟡 `pmd:AtLeastOneConstructor` L148 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L149 Missing commented default access modifier on field 'CONST' - 🟡 `pmd:FinalFieldCouldBeStatic` L149 final 字段可以声明为 static 建议: 若字段是编译时常量，请声明为 static final。 - 🟡 `pmd:AtLeastOneConstructor` L153 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L154 Missing commented default access modifier on method 'm1(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L154 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:CommentDefaultAccessModifier` L157 Missing commented default access modifier on method 'm2(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L157 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:CommentDefaultAccessModifier` L160 Missing commented default access modifier on method 'm3(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L160 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:CommentDefaultAccessModifier` L163 Missing commented default access modifier on method 'm4(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L163 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:CommentDefaultAccessModifier` L166 Missing commented default access modifier on method 'm5(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L166 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:CommentDefaultAccessModifier` L169 Missing commented default access modifier on method 'm6(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L169 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:CommentDefaultAccessModifier` L172 Missing commented default access modifier on method 'm7(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L172 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:CommentDefaultAccessModifier` L175 Missing commented default access modifier on method 'm8(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L175 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:CommentDefaultAccessModifier` L178 Missing commented default access modifier on method 'm9(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L178 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:CommentDefaultAccessModifier` L181 Missing commented default access modifier on method 'm10(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L181 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:CommentDefaultAccessModifier` L184 Missing commented default access modifier on method 'm11(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L184 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:CommentDefaultAccessModifier` L187 Missing commented default access modifier on method 'm12(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L187 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:CommentDefaultAccessModifier` L190 Missing commented default access modifier on method 'm13(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L190 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:CommentDefaultAccessModifier` L193 Missing commented default access modifier on method 'm14(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L193 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:CommentDefaultAccessModifier` L196 Missing commented default access modifier on method 'm15(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L196 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:CommentDefaultAccessModifier` L199 Missing commented default access modifier on method 'm16(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L199 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:CommentDefaultAccessModifier` L202 Missing commented default access modifier on method 'm17(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L202 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:CommentDefaultAccessModifier` L205 Missing commented default access modifier on method 'm18(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L205 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:CommentDefaultAccessModifier` L208 Missing commented default access modifier on method 'm19(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L208 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:CommentDefaultAccessModifier` L211 Missing commented default access modifier on method 'm20(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L211 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:CommentDefaultAccessModifier` L214 Missing commented default access modifier on method 'm21(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L214 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:CommentDefaultAccessModifier` L217 Missing commented default access modifier on method 'm22(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L217 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:CommentDefaultAccessModifier` L220 Missing commented default access modifier on method 'm23(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L220 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:CommentDefaultAccessModifier` L223 Missing commented default access modifier on method 'm24(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L223 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:CommentDefaultAccessModifier` L226 Missing commented default access modifier on method 'm25(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L226 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:CommentDefaultAccessModifier` L229 Missing commented default access modifier on method 'm26(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L229 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:CommentDefaultAccessModifier` L232 Missing commented default access modifier on method 'm27(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L232 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:CommentDefaultAccessModifier` L235 Missing commented default access modifier on method 'm28(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L235 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:CommentDefaultAccessModifier` L238 Missing commented default access modifier on method 'm29(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L238 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:CommentDefaultAccessModifier` L241 Missing commented default access modifier on method 'm30(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L241 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:CommentDefaultAccessModifier` L244 Missing commented default access modifier on method 'm31(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L244 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:CommentDefaultAccessModifier` L247 Missing commented default access modifier on method 'm32(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L247 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:CommentDefaultAccessModifier` L250 Missing commented default access modifier on method 'm33(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L250 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:CommentDefaultAccessModifier` L253 Missing commented default access modifier on method 'm34(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L253 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:CommentDefaultAccessModifier` L256 Missing commented default access modifier on method 'm35(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L256 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:CommentDefaultAccessModifier` L259 Missing commented default access modifier on method 'm36(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L259 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:CommentDefaultAccessModifier` L262 Missing commented default access modifier on method 'm37(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L262 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:CommentDefaultAccessModifier` L265 Missing commented default access modifier on method 'm38(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L265 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:CommentDefaultAccessModifier` L268 Missing commented default access modifier on method 'm39(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L268 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:CommentDefaultAccessModifier` L271 Missing commented default access modifier on method 'm40(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L271 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:CommentDefaultAccessModifier` L274 Missing commented default access modifier on method 'm41(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L274 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:CommentDefaultAccessModifier` L277 Missing commented default access modifier on method 'm42(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L277 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:CommentDefaultAccessModifier` L280 Missing commented default access modifier on method 'm43(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L280 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:CommentDefaultAccessModifier` L283 Missing commented default access modifier on method 'm44(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L283 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:CommentDefaultAccessModifier` L286 Missing commented default access modifier on method 'm45(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L286 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:CommentDefaultAccessModifier` L289 Missing commented default access modifier on method 'm46(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L289 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:CommentDefaultAccessModifier` L292 Missing commented default access modifier on method 'm47(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L292 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:CommentDefaultAccessModifier` L295 Missing commented default access modifier on method 'm48(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L295 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:CommentDefaultAccessModifier` L298 Missing commented default access modifier on method 'm49(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L298 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:CommentDefaultAccessModifier` L301 Missing commented default access modifier on method 'm50(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L301 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:UnusedPrivateField` L308 存在未使用的私有字段 建议: 删除该字段，或确认其确实被需要后补充使用。 - 🟡 `pmd:ImmutableField` L308 字段可以声明为 final 建议: 初始化后不再变更的字段应添加 final 修饰符。 - 🟡 `pmd:UnnecessaryConstructor` L310 构造函数不必要，编译器会生成默认构造 建议: 删除空的、无实际逻辑的构造函数。 - 🟡 `pmd:CommentDefaultAccessModifier` L310 Missing commented default access modifier on constructor 'Immut()' - 🟡 `pmd:AtLeastOneConstructor` L315 Each class should declare at least one constructor - 🟡 `pmd:PublicMemberInNonPublicType` L317 Public member 'getname' declared in a non-public type - 🟡 `pmd:PublicMemberInNonPublicType` L320 Public member 'setname' declared in a non-public type - 🟡 `pmd:MethodArgumentCouldBeFinal` L320 Parameter 'n' is not assigned and could be declared final - 🟡 `pmd:AtLeastOneConstructor` L326 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L327 Missing commented default access modifier on method 'bad(A)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L327 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:LawOfDemeter` L328 Call to `getB` on foreign value `a` (degree 1) - 🟡 `pmd:AtLeastOneConstructor` L330 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L330 Missing commented default access modifier on nested class 'A' - 🟡 `pmd:CommentDefaultAccessModifier` L331 Missing commented default access modifier on method 'getB()' - 🟡 `pmd:AtLeastOneConstructor` L335 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L335 Missing commented default access modifier on nested class 'B' - 🟡 `pmd:CommentDefaultAccessModifier` L336 Missing commented default access modifier on method 'getC()' - 🟡 `pmd:AtLeastOneConstructor` L340 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L340 Missing commented default access modifier on nested class 'C' - 🟡 `pmd:CommentDefaultAccessModifier` L341 Missing commented default access modifier on method 'doIt()' - 🟡 `pmd:AtLeastOneConstructor` L347 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L348 Missing commented default access modifier on method 'bad(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L348 Parameter 'x' is not assigned and could be declared final - 🟡 `pmd:SimplifyBooleanReturns` L349 该 if 语句可被替换为返回条件表达式 建议: 例如 if (x) return true; else return false 应改为 return x; - 🟡 `pmd:LogicInversion` L349 Use opposite operator instead of the logic complement operator. - 🟡 `pmd:OnlyOneReturn` L350 方法应只有唯一出口，且应在最后一条语句 建议: 将多个 return 改为单出口风格，或使用表达式结果返回。 - 🟡 `pmd:UseUtilityClass` L359 所有成员都是静态的，应添加私有构造防止实例化 建议: 为工具类添加 private 无参构造函数，并将类声明为 final。 - 🟡 `pmd:MutableStaticState` L360 不要使用非 final 非私有的静态字段 建议: 改为 private static final，或通过 getter/setter 控制访问。 - 🟡 `pmd:CommentDefaultAccessModifier` L360 Missing commented default access modifier on field 'counter' - 🟡 `pmd:AtLeastOneConstructor` L364 Each class should declare at least one constructor - 🟡 `pmd:PublicMemberInNonPublicType` L365 Public member 'x' declared in a non-public type - 🟡 `pmd:AtLeastOneConstructor` L369 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L370 Missing commented default access modifier on method 'bad()' - 🟡 `pmd:SignatureDeclareThrowsException` L370 方法/构造函数不应显式抛出 java.lang.Exception 建议: 抛出具体异常类型，避免宽泛的 Exception。 - 🟡 `pmd:AtLeastOneConstructor` L375 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L376 Missing commented default access modifier on method 'bad(boolean)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L376 Parameter 'x' is not assigned and could be declared final - 🟡 `pmd:SimplifiedTernary` L377 三元表达式可以简化 建议: 例如 return x ? true : false 应改为 return x。 - 🟡 `pmd:AtLeastOneConstructor` L382 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L383 Missing commented default access modifier on method 'bad(boolean)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L383 Parameter 'x' is not assigned and could be declared final - 🟡 `pmd:SimplifyBooleanExpressions` L384 布尔表达式包含不必要的比较 建议: 例如 return x == true 应改为 return x。 - 🟡 `pmd:AtLeastOneConstructor` L389 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L390 Missing commented default access modifier on method 'bad(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L390 Parameter 'x' is not assigned and could be declared final - 🟡 `pmd:SimplifyBooleanReturns` L391 This if statement can be replaced by `return {condition};` - 🟡 `pmd:OnlyOneReturn` L392 A method should have only one exit point, and that should be the last statement in the method - 🟡 `pmd:AtLeastOneConstructor` L400 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L401 Missing commented default access modifier on method 'bar(Object)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L401 Parameter 'x' is not assigned and could be declared final - 🟡 `pmd:EmptyControlStatement` L402 存在空的控制语句（if/for/while 等） 建议: 补充逻辑或删除空语句块。 - 🟡 `pmd:SimplifyConditional` L402 instanceof 前不需要检查 null 建议: 删除 x != null &&，因为 x instanceof List 已覆盖 null 情况。 - 🟡 `pmd:AtLeastOneConstructor` L408 Each class should declare at least one constructor - 🟡 `pmd:SingularField` L409 字段可能应改为局部变量 建议: 如果字段只在一个方法中使用，请改为方法内局部变量。 - 🟡 `pmd:PublicMemberInNonPublicType` L411 Public member 'foo' declared in a non-public type - 🟡 `pmd:MethodArgumentCouldBeFinal` L411 Parameter 'y' is not assigned and could be declared final - 🟡 `pmd:AtLeastOneConstructor` L418 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L419 Missing commented default access modifier on method 'bad(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L419 Parameter 'x' is not assigned and could be declared final - 🟡 `pmd:SwitchDensity` L420 switch 中语句与分支比例过高 建议: 将每个 case 的逻辑抽取为独立方法，或使用多态/映射表重构。 - 🟡 `pmd:AtLeastOneConstructor` L471 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L472 Missing commented default access modifier on method 'm()' - 🟡 `pmd:AtLeastOneConstructor` L475 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L477 Missing commented default access modifier on method 'm()' - 🟡 `pmd:UselessOverridingMethod` L477 重写方法仅调用 super，无实际用途 建议: 删除该重写方法，让父类方法直接生效。 - 🟡 `pmd:UseUtilityClass` L483 All members are static. Consider adding a private no-args constructor to prevent instantiation. - 🟡 `pmd:CommentDefaultAccessModifier` L484 Missing commented default access modifier on method 'helper()' - 🟡 `pmd:AtLeastOneConstructor` L491 Each class should declare at least one constructor - 🟡 `pmd:PublicMemberInNonPublicType` L492 Public member 'bar' declared in a non-public type - 🟡 `pmd:MethodArgumentCouldBeFinal` L492 Parameter 'x' is not assigned and could be declared final - 🟡 `pmd:AtLeastOneConstructor` L525 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L526 Missing commented default access modifier on method 'bar(Object, String)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L526 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:MethodArgumentCouldBeFinal` L526 Parameter 'baz' is not assigned and could be declared final - 🟡 `pmd:MisplacedNullCheck` L527 null 检查位置错误，可能引发 NullPointerException 建议: 先判空再调用方法，例如 a != null && a.equals(baz)。 - 🟡 `pmd:AtLeastOneConstructor` L536 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L537 Missing commented default access modifier on method 'bad(int)' - 🟡 `pmd:AssignmentInOperand` L538 避免在操作数中赋值 建议: 将赋值移到表达式外，单独一行，再参与判断。 - 🟡 `pmd:UseUtilityClass` L545 All members are static. Consider adding a private no-args constructor to prevent instantiation. - 🟡 `pmd:MutableStaticState` L546 Do not use non-final non-private static fields - 🟡 `pmd:CommentDefaultAccessModifier` L546 Missing commented default access modifier on field 'counter' - 🟡 `pmd:CommentDefaultAccessModifier` L548 Missing commented default access modifier on constructor 'AssignStatic()' - 🟡 `pmd:AssignmentToNonFinalStatic` L549 构造函数中给非 final 静态字段赋值可能不安全 建议: 使用实例字段，或通过 static final/初始化块管理静态状态。 - 🟡 `pmd:AtLeastOneConstructor` L554 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L555 Missing commented default access modifier on method 'bad()' - 🟡 `pmd:SignatureDeclareThrowsException` L555 A method/constructor should not explicitly throw java.lang.Exception - 🟡 `pmd:LocalVariableCouldBeFinal` L556 局部变量可声明为 final 建议: 为只赋值一次的局部变量添加 final 修饰符。 - 🟡 `pmd:AvoidAccessibilityAlteration` L557 不应使用 setAccessible(true) 修改可见性 建议: 避免反射破坏封装；若必须，应评估安全风险并限制调用权限。 - 🟡 `pmd:AtLeastOneConstructor` L562 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L563 Missing commented default access modifier on method 'bad()' - 🟡 `pmd:LocalVariableCouldBeFinal` L564 Local variable 'o' could be declared final - 🟡 `pmd:AvoidCallingFinalize` L565 避免显式调用 finalize() 方法 建议: 删除显式调用，改用 try-with-resources 或 Cleaner 管理资源。 - 🟡 `pmd:AtLeastOneConstructor` L570 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L571 Missing commented default access modifier on field 'd' - 🟡 `pmd:AvoidDecimalLiteralsInBigDecimalConstructor` L571 避免用浮点字面量构造 BigDecimal，可能产生精度问题 建议: 使用字符串构造：new BigDecimal("0.1")。 - 🟡 `pmd:AtLeastOneConstructor` L575 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L576 Missing commented default access modifier on method 'bad()' - 🟡 `pmd:AtLeastOneConstructor` L583 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L584 Missing commented default access modifier on method 'bad(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L584 Parameter 'x' is not assigned and could be declared final - 🟡 `pmd:AvoidLiteralsInIfCondition` L585 if 条件中避免使用魔术数字/字面量 建议: 将 42、5 等常量提取为命名常量。 - 🟡 `pmd:AtLeastOneConstructor` L592 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L593 Missing commented default access modifier on method 'bad()' - 🟡 `pmd:AssignmentInOperand` L596 Avoid assignment to x in operand - 🟡 `pmd:AtLeastOneConstructor` L602 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L603 Missing commented default access modifier on field 'x' - 🟡 `pmd:AvoidUsingOctalValues` L603 避免使用八进制字面量 建议: 去掉前导 0，或明确使用 0x/0b 前缀。 - 🟡 `pmd:AtLeastOneConstructor` L607 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L608 Missing commented default access modifier on method 'bad(Object, Object)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L608 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:MethodArgumentCouldBeFinal` L608 Parameter 'b' is not assigned and could be declared final - 🟡 `pmd:EmptyControlStatement` L609 Empty if statement - 🟡 `pmd:AtLeastOneConstructor` L615 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L616 Missing commented default access modifier on method 'bad()' - 🟡 `pmd:UselessPureMethodCall` L618 调用了纯方法但未使用结果 建议: 删除该调用，或将结果赋给变量并使用。 - 🟡 `pmd:CommentDefaultAccessModifier` L620 Missing commented default access modifier on method 'doSomething()' - 🟡 `pmd:AtLeastOneConstructor` L625 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L626 Missing commented default access modifier on method 'bad()' - 🟡 `pmd:UselessPureMethodCall` L627 Do not call pure method toString if the result is not used. - 🟡 `pmd:CommentDefaultAccessModifier` L630 Missing commented default access modifier on method 'doSomething()' - 🟡 `pmd:AtLeastOneConstructor` L635 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L636 Missing commented default access modifier on method 'bad()' - 🟡 `pmd:CloseResource` L637 资源使用后应关闭 建议: 使用 try-with-resources 自动关闭 InputStream 等资源。 - 🟡 `pmd:LocalVariableCouldBeFinal` L637 Local variable 'in' could be declared final - 🟡 `pmd:CheckSkipResult` L638 应检查 InputStream.skip() 的返回值 建议: 将 skip 返回值赋给变量，并判断是否满足所需跳过字节数。 - 🟡 `pmd:AtLeastOneConstructor` L643 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L644 Missing commented default access modifier on method 'bad(Collection)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L644 Parameter 'c' is not assigned and could be declared final - 🟡 `pmd:UnusedLocalVariable` L645 存在未使用的局部变量 建议: 删除未使用的局部变量，或补全其使用逻辑。 - 🟡 `pmd:ClassCastExceptionWithToArray` L645 Collection.toArray() 的使用会抛出 ClassCastException 建议: 使用 c.toArray(new String[0]) 传入类型化数组。 - 🟡 `pmd:AtLeastOneConstructor` L650 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L651 Missing commented default access modifier on method 'bad()' - 🟡 `pmd:LocalVariableCouldBeFinal` L652 Local variable 'in' could be declared final - 🟡 `pmd:AtLeastOneConstructor` L658 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L659 Missing commented default access modifier on method 'bad()' - 🟡 `pmd:UnusedLocalVariable` L660 Avoid unused local variables such as 'l'. - 🟡 `pmd:UnusedLocalVariable` L661 Avoid unused local variables such as 'o'. - 🟡 `pmd:PrimitiveWrapperInstantiation` L661 不要使用 new Integer(...)，应使用 Integer.valueOf(...) 建议: 使用装箱缓存或 Integer.valueOf 替代 new Integer。 - 🟡 `pmd:UnnecessaryBoxing` L661 存在不必要的显式装箱 建议: 直接使用基本类型或依赖自动装箱。 - 🟡 `pmd:AtLeastOneConstructor` L666 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L667 Missing commented default access modifier on method 'bad(String, String)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L667 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:MethodArgumentCouldBeFinal` L667 Parameter 'b' is not assigned and could be declared final - 🟡 `pmd:EmptyControlStatement` L668 Empty if statement - 🟡 `pmd:CompareObjectsWithEquals` L668 比较对象引用应使用 equals() 而不是 == 建议: 对非基本类型对象比较使用 equals()。 - 🟡 `pmd:UseEqualsToCompareStrings` L668 比较字符串应使用 equals() 而不是 == 建议: 使用 a.equals(b)，并按需调用 equalsIgnoreCase。 - 🟡 `pmd:AtLeastOneConstructor` L674 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L675 Missing commented default access modifier on method 'bad(double)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L675 Parameter 'x' is not assigned and could be declared final - 🟡 `pmd:EmptyControlStatement` L676 Empty if statement - 🟡 `pmd:ComparisonWithNaN` L676 与 NaN 比较恒为 false 建议: 使用 Double.isNaN(x) 判断 NaN。 - 🟡 `pmd:AtLeastOneConstructor` L682 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L683 Missing commented default access modifier on method 'call()' - 🟡 `pmd:CommentDefaultAccessModifier` L686 Missing commented default access modifier on method 'accept(String[])' - 🟡 `pmd:CommentDefaultAccessModifier` L692 Missing commented default access modifier on constructor 'CtorCall()' - 🟡 `pmd:CommentDefaultAccessModifier` L695 Missing commented default access modifier on method 'overridable()' - 🟡 `pmd:AtLeastOneConstructor` L700 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L701 Missing commented default access modifier on method 'bad()' - 🟡 `pmd:MissingSerialVersionUID` L707 Classes implementing Serializable should set a serialVersionUID - 🟡 `pmd:AtLeastOneConstructor` L707 Each class should declare at least one constructor - 🟡 `pmd:DoNotExtendJavaLangThrowable` L707 异常不应直接继承 java.lang.Throwable 建议: 应继承 Exception 或 RuntimeException。 - 🟡 `pmd:AtLeastOneConstructor` L711 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L712 Missing commented default access modifier on field 'path' - 🟡 `pmd:DoNotHardCodeSDCard` L712 不要硬编码 /sdcard 路径 建议: 使用环境变量或上下文 API 获取存储路径。 - 🟡 `pmd:AtLeastOneConstructor` L716 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L717 Missing commented default access modifier on method 'bad()' - 🟡 `pmd:DoNotTerminateVM` L718 不应调用 System.exit() 终止 JVM 建议: 通过受控方式结束应用，或抛出异常交给上层处理。 - 🟡 `pmd:AtLeastOneConstructor` L723 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L724 Missing commented default access modifier on method 'bad()' - 🟡 `pmd:CommentDefaultAccessModifier` L731 Missing commented default access modifier on method 'doWork()' - 🟡 `pmd:AtLeastOneConstructor` L736 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L737 Missing commented default access modifier on method 'bad()' - 🟡 `pmd:DontUseFloatTypeForLoopIndices` L738 不要使用浮点类型作为循环索引，浮点精度可能导致循环异常 建议: 改用 int/long 循环变量，或使用 double 并明确终止条件。 - 🟡 `pmd:EmptyControlStatement` L738 Empty for statement - 🟡 `pmd:AtLeastOneConstructor` L744 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L745 Missing commented default access modifier on method 'bad()' - 🟡 `pmd:EmptyCatchBlock` L748 避免空 catch 块 建议: 至少记录日志或做降级处理，不要静默吞掉异常。 - 🟡 `pmd:AvoidCatchingGenericException` L748 避免捕获泛化 Exception 建议: 捕获具体异常类型，如 IOException、IllegalArgumentException。 - 🟡 `pmd:CommentDefaultAccessModifier` L751 Missing commented default access modifier on method 'doWork()' - 🟡 `pmd:AtLeastOneConstructor` L756 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L757 Missing commented default access modifier on method 'bad(Object)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L757 Parameter 'o' is not assigned and could be declared final - 🟡 `pmd:EmptyControlStatement` L758 Empty if statement - 🟡 `pmd:AtLeastOneConstructor` L764 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L765 Missing commented default access modifier on method 'bad(String)' - 🟡 `pmd:AtLeastOneConstructor` L773 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L774 Missing commented default access modifier on method 'bad(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L774 Parameter 'x' is not assigned and could be declared final - 🟡 `pmd:IdenticalConditionalBranches` L775 条件分支完全相同，条件判断无意义 建议: 删除 if/else，直接返回相同结果或提取公共逻辑。 - 🟡 `pmd:OnlyOneReturn` L776 A method should have only one exit point, and that should be the last statement in the method - 🟡 `pmd:AtLeastOneConstructor` L784 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L785 Missing commented default access modifier on method 'bad(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L785 Parameter 'x' is not assigned and could be declared final - 🟡 `pmd:ImplicitSwitchFallThrough` L789 switch 分支存在隐式 fall-through 建议: 在 case 末尾补上 break/return，或添加注释明确故意 fall-through。 - 🟡 `pmd:AtLeastOneConstructor` L799 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L800 Missing commented default access modifier on method 'bad()' - 🟡 `pmd:UnusedLocalVariable` L801 Avoid unused local variables such as 'c'. - 🟡 `pmd:PrimitiveWrapperInstantiation` L801 Do not use `new Integer(...)`, prefer `Integer.valueOf(...)` - 🟡 `pmd:AtLeastOneConstructor` L806 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L807 Missing commented default access modifier on method 'bad()' - 🟡 `pmd:ForLoopVariableCount` L808 for 循环中控制变量过多 建议: 拆分循环或将额外变量移到循环外，保持循环头简洁。 - 🟡 `pmd:AvoidReassigningLoopVariables` L809 避免修改循环控制变量 建议: 不要在循环体内或内层循环更新外层循环变量，使用独立变量。 - 🟡 `pmd:AtLeastOneConstructor` L815 Each class should declare at least one constructor - 🟡 `pmd:MethodWithSameNameAsEnclosingClass` L816 方法与包含它的类同名（可能误当构造函数） 建议: 重命名方法，避免与类名混淆。 - 🟡 `pmd:CommentDefaultAccessModifier` L816 Missing commented default access modifier on method 'SameName()' - 🟡 `pmd:AtLeastOneConstructor` L821 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L822 Missing commented default access modifier on method 'bad(String)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L822 Parameter 's' is not assigned and could be declared final - 🟡 `pmd:EmptyControlStatement` L823 Empty if statement - 🟡 `pmd:MissingStaticMethodInNonInstantiatableClass` L829 Class cannot be instantiated and does not provide any static methods or fields - 🟡 `pmd:UnusedPrivateField` L836 Avoid unused private fields such as 'LOG1'. - 🟡 `pmd:UnusedPrivateField` L837 Avoid unused private fields such as 'LOG2'. - 🟡 `pmd:AtLeastOneConstructor` L841 Each class should declare at least one constructor - 🟡 `pmd:NonStaticInitializer` L842 非静态初始化器令人困惑 建议: 将初始化逻辑移到构造函数或工厂方法中。 - 🟡 `pmd:AtLeastOneConstructor` L848 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L849 Missing commented default access modifier on field 's' - 🟡 `pmd:CommentDefaultAccessModifier` L850 Missing commented default access modifier on method 'bad()' - 🟡 `pmd:NullAssignment` L851 将对象赋值为 null 是代码坏味道 建议: 用 Optional 或空集合/空对象模式替代 null 赋值。 - 🟡 `pmd:AtLeastOneConstructor` L856 Each class should declare at least one constructor - 🟡 `pmd:OverrideBothEqualsAndHashcode` L857 重写 equals() 时应同时重写 hashCode() 建议: 为相等的对象保证 hashCode 一致，避免集合类行为异常。 - 🟡 `pmd:MissingOverride` L857 重写方法缺少 @Override 注解 建议: 在继承或实现的方法上添加 @Override 注解。 - 🟡 `pmd:AtLeastOneConstructor` L863 Each class should declare at least one constructor - 🟡 `pmd:MissingOverride` L864 The method 'compareTo(CmpOnly)' is missing an @Override annotation. - 🟡 `pmd:OverrideBothEqualsAndHashCodeOnComparable` L864 实现 Comparable 时应同时重写 equals() 和 hashCode() 建议: 保持 compareTo、equals、hashCode 三者语义一致。 - 🟡 `pmd:AtLeastOneConstructor` L870 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L871 Missing commented default access modifier on field 'c' - 🟡 `pmd:ReplaceJavaUtilCalendar` L871 应使用 java.time 替代 java.util.Calendar 建议: 使用 LocalDate/LocalDateTime/ZonedDateTime 等新时间 API。 - 🟡 `pmd:AtLeastOneConstructor` L875 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L876 Missing commented default access modifier on field 'd' - 🟡 `pmd:ReplaceJavaUtilDate` L876 应使用 java.time 替代 java.util.Date 建议: 使用 Instant/LocalDateTime 并配合 DateTimeFormatter 处理格式。 - 🟡 `pmd:ReplaceJavaUtilDate` L876 Usage of java.util.Date should be replaced with classes from java.time - 🟡 `pmd:AtLeastOneConstructor` L880 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L881 Missing commented default access modifier on method 'bad()' - 🟡 `pmd:AtLeastOneConstructor` L887 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L888 Missing commented default access modifier on method 'bad()' - 🟡 `pmd:OnlyOneReturn` L890 A method should have only one exit point, and that should be the last statement in the method - 🟡 `pmd:ReturnFromFinallyBlock` L892 避免在 finally 块中返回值 建议: 从 try/catch 中返回结果，finally 只做资源清理。 - 🟡 `pmd:AtLeastOneConstructor` L898 Each class should declare at least one constructor - 🟡 `pmd:AvoidFieldNameMatchingTypeName` L899 字段名与类名相同容易混淆 建议: 重命名字段，例如 sdf 改为 dateFormat。 - 🟡 `pmd:CommentDefaultAccessModifier` L899 Missing commented default access modifier on field 'sdf' - 🟡 `pmd:SimpleDateFormatNeedsLocale` L899 SimpleDateFormat 实例化时应指定 Locale 建议: new SimpleDateFormat("yyyy-MM-dd", Locale.ROOT)。 - 🟡 `pmd:AtLeastOneConstructor` L903 Each class should declare at least one constructor - 🟡 `pmd:AvoidStringBufferField` L904 StringBuffer 字段可能造成内存问题 建议: 优先使用 StringBuilder，并避免在长生命周期对象中持有大缓冲区。 - 🟡 `pmd:CommentDefaultAccessModifier` L904 Missing commented default access modifier on field 'sb' - 🟡 `pmd:AtLeastOneConstructor` L908 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L909 Missing commented default access modifier on method 'equals(String)' - 🟡 `pmd:AtLeastOneConstructor` L914 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L915 Missing commented default access modifier on method 'hashcode()' - 🟡 `pmd:AtLeastOneConstructor` L920 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L921 Missing commented default access modifier on field 's' - 🟡 `pmd:AtLeastOneConstructor` L925 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L926 Missing commented default access modifier on method 'bad()' - 🟡 `pmd:UnconditionalIfStatement` L927 不要使用恒真/恒假的 if 语句 建议: 删除无条件 if，直接执行其中的代码或删除整个语句块。 - 🟡 `pmd:AtLeastOneConstructor` L934 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L935 Missing commented default access modifier on method 'bad(String)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L935 Parameter 's' is not assigned and could be declared final - 🟡 `pmd:EmptyControlStatement` L936 Empty if statement - 🟡 `pmd:AtLeastOneConstructor` L942 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L943 Missing commented default access modifier on method 'bad(int)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L943 Parameter 'x' is not assigned and could be declared final - 🟡 `pmd:UnusedLocalVariable` L944 Avoid unused local variables such as 's'. - 🟡 `pmd:UnnecessaryConversionTemporary` L944 避免不必要的临时转换对象 建议: 使用 String.valueOf(x) 替代 new Integer(x).toString()。 - 🟡 `pmd:PrimitiveWrapperInstantiation` L944 Do not use `new Integer(...)`, prefer `Integer.valueOf(...)` - 🟡 `pmd:AtLeastOneConstructor` L949 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L950 Missing commented default access modifier on field 's' - 🟡 `pmd:OverrideBothEqualsAndHashcode` L951 Ensure you override both equals() and hashCode() - 🟡 `pmd:MissingOverride` L951 The method 'equals(Object)' is missing an @Override annotation. - 🟡 `pmd:MethodArgumentCouldBeFinal` L951 Parameter 'o' is not assigned and could be declared final - 🟡 `pmd:EmptyControlStatement` L952 Empty if statement - 🟡 `pmd:AtLeastOneConstructor` L959 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L960 Missing commented default access modifier on method 'bad(String, String)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L960 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:MethodArgumentCouldBeFinal` L960 Parameter 'b' is not assigned and could be declared final - 🟡 `pmd:CompareObjectsWithEquals` L961 Use equals() to compare object references. - 🟡 `pmd:UseEqualsToCompareStrings` L961 Use equals() to compare strings instead of '==' or '!=' - 🟡 `pmd:AtLeastOneConstructor` L966 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L967 Missing commented default access modifier on method 'bad()' - 🟡 `pmd:UselessPureMethodCall` L968 Do not call pure method length if the result is not used. - 🟡 `pmd:AtLeastOneConstructor` L973 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L974 Missing commented default access modifier on method 'bad(String)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L974 Parameter 's' is not assigned and could be declared final - 🟡 `pmd:UselessPureMethodCall` L975 Do not call pure method toUpperCase if the result is not used. - 🟡 `pmd:UseLocaleWithCaseConversions` L975 toUpperCase()/toLowerCase() 应指定 Locale 建议: 使用 s.toUpperCase(Locale.ROOT) 或指定业务 locale。 - 🟡 `pmd:AtLeastOneConstructor` L980 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L981 Missing commented default access modifier on method 'bad()' - 🟡 `pmd:UnusedLocalVariable` L982 Avoid unused local variables such as 'cl'. - 🟡 `pmd:UseProperClassLoader` L982 getClassLoader() 在 J2EE 中可能不符合预期 建议: 使用 Thread.currentThread().getContextClassLoader()。 - 🟡 `pmd:AtLeastOneConstructor` L987 Each class should declare at least one constructor - 🟡 `pmd:AvoidFieldNameMatchingMethodName` L988 字段名与同名方法容易混淆 建议: 重命名字段或方法，避免同名歧义。 - 🟡 `pmd:CommentDefaultAccessModifier` L988 Missing commented default access modifier on field 'value' - 🟡 `pmd:CommentDefaultAccessModifier` L990 Missing commented default access modifier on method 'value()' - 🟡 `pmd:AtLeastOneConstructor` L995 Each class should declare at least one constructor - 🟡 `pmd:AvoidFieldNameMatchingTypeName` L996 It is somewhat confusing to have a field name matching the declaring class name - 🟡 `pmd:CommentDefaultAccessModifier` L996 Missing commented default access modifier on field 'TypeName' - 🟡 `pmd:AtLeastOneConstructor` L1000 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L1001 Missing commented default access modifier on method 'bad()' - 🟡 `pmd:AvoidCatchingGenericException` L1004 Avoid catching Exception in try-catch block - 🟡 `pmd:EmptyControlStatement` L1005 Empty if statement - 🟡 `pmd:AvoidInstanceofChecksInCatchClause` L1005 catch 块中不应使用 instanceof 判断异常类型 建议: 为每种异常类型增加独立的 catch 子句。 - 🟡 `pmd:CommentDefaultAccessModifier` L1009 Missing commented default access modifier on method 'doWork()' - 🟡 `pmd:AtLeastOneConstructor` L1014 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L1015 Missing commented default access modifier on method 'bad()' - 🟡 `pmd:LocalVariableCouldBeFinal` L1016 Local variable 'x' could be declared final - 🟡 `pmd:TooFewBranchesForSwitch` L1017 switch 分支少于三个，使用 if 更高效 建议: 将 switch 改为 if/else if 判断。 - 🟡 `pmd:NonExhaustiveSwitch` L1017 switch 不完整，应包含 default 或所有枚举分支 建议: 补充 default 分支处理未知情况。 - 🟡 `pmd:NonCaseLabelInSwitch` L1020 switch 中出现了非 case 标签 建议: 移除标签，或重构 switch 逻辑。 - 🟡 `pmd:UnusedLabel` L1020 存在未使用的标签 建议: 删除未引用标签，避免误导。 - 🟡 `pmd:PublicMemberInNonPublicType` L1035 Public member 'getInstance' declared in a non-public type - 🟡 `pmd:PublicMemberInNonPublicType` L1039 Public member 'getInstance' declared in a non-public type - 🟡 `pmd:MethodArgumentCouldBeFinal` L1039 Parameter 'obj' is not assigned and could be declared final - 🟡 `pmd:VariableCanBeInlined` L1040 局部变量可以内联，不需要额外存储 建议: 直接返回值或表达式，减少中间变量。 - 🟡 `pmd:LocalVariableCouldBeFinal` L1040 Local variable 's' could be declared final - 🟡 `pmd:SignatureDeclareThrowsException` L1047 A method/constructor should not explicitly throw java.lang.Exception - 🟡 `pmd:UnsupportedJdkApiUsage` L1048 使用了不受支持的 JDK API（如 sun.misc.Unsafe） 建议: 改用标准 JDK API，例如 VarHandle/Atomic 类或通过受支持方式获取 Unsafe。 - 🟡 `pmd:AtLeastOneConstructor` L1053 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L1054 Missing commented default access modifier on method 'bar()' - 🟡 `pmd:IdempotentOperations` L1056 存在幂等操作（如变量赋值给自身/重复转换） 建议: 删除重复或自我赋值，保留一次有效操作。 - 🟡 `pmd:UnusedAssignment` L1056 The value assigned to variable 'x' is never used - 🟡 `pmd:AtLeastOneConstructor` L1061 Each class should declare at least one constructor - 🟡 `pmd:PublicMemberInNonPublicType` L1062 Public member 'hashcode' declared in a non-public type - 🟡 `pmd:SuspiciousHashcodeMethodName` L1062 方法名与 hashCode() 高度相似，但签名不符 建议: 重命名为 hashcode -> hashCode，并返回 int 且加上 @Override。 - 🟡 `pmd:AtLeastOneConstructor` L1068 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L1069 Missing commented default access modifier on method 'foo()' - 🟡 `pmd:SuspiciousOctalEscape` L1070 字符串中的八进制转义后紧跟数字字符很可疑 建议: 将转义拆分或改用 Unicode 转义，避免歧义。 - 🟡 `pmd:AtLeastOneConstructor` L1075 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L1076 Missing commented default access modifier on method 'bad(String)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L1076 Parameter 'buz' is not assigned and could be declared final - 🟡 `pmd:LocalVariableCouldBeFinal` L1077 Local variable 'answer' could be declared final - 🟡 `pmd:LiteralsFirstInComparisons` L1077 字符串比较时应将字面量放在前面 建议: 使用 "BAZ".equals(buz) 避免 NPE。 - 🟡 `pmd:UnnecessaryCaseChange` L1077 使用 toUpperCase/toLowerCase().equals() 不如 equalsIgnoreCase 清晰 建议: 改为 s1.equalsIgnoreCase(s2)。 - 🟡 `pmd:UseLocaleWithCaseConversions` L1077 When doing a String.toLowerCase()/toUpperCase() call, use a Locale - 🟡 `pmd:AtLeastOneConstructor` L1083 Each class should declare at least one constructor - 🟡 `pmd:PublicMemberInNonPublicType` L1084 Public member 'method1' declared in a non-public type - 🟡 `pmd:PublicMemberInNonPublicType` L1087 Public member 'method' declared in a non-public type - 🟡 `pmd:MethodArgumentCouldBeFinal` L1087 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:UnusedNullCheckInEquals` L1088 equals() 中的 null 检查未被使用或位置不当 建议: 直接调用非空对象.equals()，或先用 Objects.equals() 统一判空。 - 🟡 `pmd:AtLeastOneConstructor` L1095 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L1097 Missing commented default access modifier on method 'bar()' - 🟡 `pmd:AvoidCatchingGenericException` L1100 Avoid catching Exception in try-catch block - 🟡 `pmd:CommentDefaultAccessModifier` L1104 Missing commented default access modifier on method 'doWork()' - 🟡 `pmd:AtLeastOneConstructor` L1109 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L1111 Missing commented default access modifier on method 'bar()' - 🟡 `pmd:AtLeastOneConstructor` L1118 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L1119 Missing commented default access modifier on method 'bar()' - 🟡 `pmd:AvoidDuplicateLiterals` L1120 字符串字面量重复出现多次 建议: 提取为常量，避免重复字符串字面量。 - 🟡 `pmd:CommentDefaultAccessModifier` L1125 Missing commented default access modifier on method 'buz(String)' - 🟡 `pmd:AtLeastOneConstructor` L1130 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L1131 Missing commented default access modifier on method 'foo()' - 🟡 `pmd:JumbledIncrementer` L1133 内层循环修改了外层循环的递增变量，循环逻辑混乱 建议: 确保内层循环更新自己的控制变量，不要更新外层循环变量。 - 🟡 `pmd:LocalVariableCouldBeFinal` L1133 Local variable 'k' could be declared final - 🟡 `pmd:AvoidReassigningLoopVariables` L1133 Avoid reassigning the loop control variable 'i' - 🟡 `pmd:AtLeastOneConstructor` L1141 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L1142 Missing commented default access modifier on method 'foo()' - 🟡 `pmd:AvoidLiteralsInIfCondition` L1144 Avoid using literals such as 5 in if statements - 🟡 `pmd:AtLeastOneConstructor` L1152 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L1153 Missing commented default access modifier on method 'bad()' - 🟡 `pmd:LocalVariableCouldBeFinal` L1154 Local variable 'numbers' could be declared final - 🟡 `pmd:CollectionTypeMismatch` L1155 集合操作使用了与泛型类型不匹配的对象 建议: 确保存入/取出/删除的元素类型与泛型一致，例如用 Integer 而不是 String。 - 🟡 `pmd:UseConcurrentHashMap` L1156 并发访问场景应使用 ConcurrentHashMap 建议: 将 HashMap 改为 ConcurrentHashMap，或同步访问。 - 🟡 `pmd:LocalVariableCouldBeFinal` L1156 Local variable 'map' could be declared final - 🟡 `pmd:UselessPureMethodCall` L1157 Do not call pure method get if the result is not used. - 🟡 `pmd:CollectionTypeMismatch` L1157 Object of type 'int' cannot be in collection expecting 'java.lang.String' - 🟡 `pmd:LocalVariableCouldBeFinal` L1158 Local variable 'names' could be declared final - 🟡 `pmd:UselessPureMethodCall` L1159 Do not call pure method contains if the result is not used. - 🟡 `pmd:CollectionTypeMismatch` L1159 Object of type 'int' cannot be in collection expecting 'java.lang.String' - 🟡 `pmd:AtLeastOneConstructor` L1164 Each class should declare at least one constructor - 🟡 `pmd:AtLeastOneConstructor` L1165 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L1165 Missing commented default access modifier on nested class 'C' - 🟡 `pmd:CommentDefaultAccessModifier` L1166 Missing commented default access modifier on method 'varargs(Object[])' - 🟡 `pmd:CommentDefaultAccessModifier` L1167 Missing commented default access modifier on method 'call()' - 🟡 `pmd:ConfusingArgumentToVarargsMethod` L1168 可变参数调用意图不清晰 建议: 显式转换为 Object 或 Object[]，或直接展开参数，避免歧义。 - 🟡 `pmd:ConfusingArgumentToVarargsMethod` L1169 Unclear if a varargs or non-varargs call is intended. Cast to Object or Object[] to clarify intent. - 🟡 `pmd:AtLeastOneConstructor` L1175 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L1176 Missing commented default access modifier on method 'bar(Object, String)' - 🟡 `pmd:MethodArgumentCouldBeFinal` L1176 Parameter 'a' is not assigned and could be declared final - 🟡 `pmd:MethodArgumentCouldBeFinal` L1176 Parameter 'baz' is not assigned and could be declared final - 🟡 `pmd:AtLeastOneConstructor` L1184 Each class should declare at least one constructor - 🟡 `pmd:UnusedPrivateField` L1186 Avoid unused private fields such as 'stream'. - 🟡 `pmd:NonSerializableClass` L1186 可序列化类包含不可序列化的字段 建议: 将该字段标记为 transient，或改为可序列化类型。 - 🟡 `pmd:AtLeastOneConstructor` L1190 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L1191 Missing commented default access modifier on method 'bad()' - 🟡 `pmd:CommentDefaultAccessModifier` L1198 Missing commented default access modifier on method 'doWork()' - 🟡 `pmd:AtLeastOneConstructor` L1204 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L1205 Missing commented default access modifier on method 'bad()' - 🟡 `pmd:AtLeastOneConstructor` L1215 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L1216 Missing commented default access modifier on method 'foo()' - 🟡 `pmd:AvoidLiteralsInIfCondition` L1219 Avoid using literals such as 25 in if statements - 🟡 `pmd:AtLeastOneConstructor` L1228 Each class should declare at least one constructor - 🟡 `pmd:CommentDefaultAccessModifier` L1229 Missing commented default access modifier on method 'foo()' - 🟡 `pmd:LocalVariableCouldBeFinal` L1230 Local variable 'i' could be declared final - 🟡 `pmd:LocalVariableCouldBeFinal` L1231 Local variable 'b' could be declared final - 🟡 `pmd:AtLeastOneConstructor` L1237 Each class should declare at least one constructor - 🟡 `pmd:PublicMemberInNonPublicType` L1238 Public member 'bar' declared in a non-public type - 🟡 `pmd:MethodArgumentCouldBeFinal` L1238 Parameter 'string' is not assigned and could be declared final - 🟡 `pmd:LiteralsFirstInComparisons` L1239 Position literals first in String comparisons - 🟡 `pmd:OnlyOneReturn` L1240 A method should have only one exit point, and that should be the last statement in the method - 🟡 `pmd:LiteralsFirstInComparisons` L1242 Position literals first in String comparisons - 🟡 `pmd:OnlyOneReturn` L1243 A method should have only one exit point, and that should be the last statement in the method - 🟡 `pmd:AtLeastOneConstructor` L1252 Each class should declare at least one constructor - 🟡 `pmd:PublicMemberInNonPublicType` L1254 Public member 'clone' declared in a non-public type - 🟡 `pmd:CloneMethodReturnTypeMustMatchClassName` L1254 clone() 返回类型必须与类名一致 建议: 将 clone() 返回类型改为当前类名。 - 🟡 `pmd:CloneMethodMustImplementCloneable` L1254 只有实现 Cloneable 接口才应实现 clone() 方法 建议: 要么移除 clone() 方法，要么让类实现 Cloneable。 - 🟡 `pmd:AtLeastOneConstructor` L1260 Each class should declare at least one constructor - 🟡 `pmd:CloneMethodReturnTypeMustMatchClassName` L1262 The return type of the clone() method must be the class name when implements Cloneable - 🟡 `pmd:CloneMethodMustBePublic` L1262 实现 Cloneable 时 clone() 方法必须为 public 建议: 将 protected clone() 改为 public CloneableType clone()。 - 🟡 `pmd:OnlyOneReturn` L1264 A method should have only one exit point, and that should be the last statement in the method - 🟡 `pmd:AtLeastOneConstructor` L1272 Each class should declare at least one constructor - 🟡 `pmd:PublicMemberInNonPublicType` L1274 Public member 'clone' declared in a non-public type - 🟡 `pmd:CloneMethodReturnTypeMustMatchClassName` L1274 The return type of the clone() method must be the class name when implements Cloneable - 🟡 `pmd:OnlyOneReturn` L1276 A method should have only one exit point, and that should be the last statement in the method - 🟡 `pmd:AtLeastOneConstructor` L1284 Each class should declare at least one constructor - 🟡 `pmd:PublicMemberInNonPublicType` L1286 Public member 'clone' declared in a non-public type - 🟡 `pmd:CloneMethodReturnTypeMustMatchClassName` L1286 The return type of the clone() method must be the class name when implements Cloneable - 🟡 `pmd:AtLeastOneConstructor` L1294 Each class should declare at least one constructor - 🟡 `pmd:EmptyFinalizer` L1296 finalize() 方法为空，没有实际作用 建议: 删除空 finalize 方法，或使用 Cleaner 清理资源。 - 🟡 `pmd:AtLeastOneConstructor` L1301 Each class should declare at least one constructor - 🟡 `pmd:FinalizeDoesNotCallSuperFinalize` L1304 finalize() 方法应最后调用 super.finalize() 建议: 在 finalize() 末尾添加 super.finalize()。 - 🟡 `pmd:CommentDefaultAccessModifier` L1306 Missing commented default access modifier on method 'cleanup()' - 🟡 `pmd:AtLeastOneConstructor` L1311 Each class should declare at least one constructor - 🟡 `pmd:FinalizeOnlyCallsSuperFinalize` L1313 finalize() 只调用 super.finalize()，没有实际清理逻辑 建议: 删除无意义的 finalize，或在其中加入真正的资源清理逻辑。 - 🟡 `pmd:AtLeastOneConstructor` L1319 Each class should declare at least one constructor - 🟡 `pmd:FinalizeOnlyCallsSuperFinalize` L1320 Finalize should do something besides just calling super.finalize() - 🟡 `pmd:MissingOverride` L1320 The method 'finalize()' is missing an @Override annotation. - 🟡 `pmd:FinalizeOverloaded` L1323 finalize 方法不应被重载 建议: 删除重载的 finalize(int) 方法。 - 🟡 `pmd:AtLeastOneConstructor` L1328 Each class should declare at least one constructor - 🟡 `pmd:FinalizeOnlyCallsSuperFinalize` L1330 Finalize should do something besides just calling super.finalize() - 🟡 `pmd:FinalizeShouldBeProtected` L1330 finalize() 应声明为 protected 建议: 将 public finalize() 改为 protected finalize()。 - 🟡 `pmd:PublicMemberInNonPublicType` L1330 Public member 'finalize' declared in a non-public type - 🟡 `pmd:AtLeastOneConstructor` L1338 Each class should declare at least one constructor - 🟡 `pmd:ProperLogger` L1339 logger 应定义为 private static final，并持有正确的类 建议: 改为 private static final Logger LOG = LoggerFactory.getLogger(Class.class); - 🟡 `pmd:AtLeastOneConstructor` L1343 Each class should declare at least one constructor - 🟡 `pmd:ProperLogger` L1344 Logger should be defined private static final and have the correct class - 🟡 `pmd:CommentDefaultAccessModifier` L1345 Missing commented default access modifier on method 'bar()' - 🟡 `pmd:AvoidCatchingGenericException` L1348 Avoid catching Exception in try-catch block - 🟡 `pmd:CommentDefaultAccessModifier` L1352 Missing commented default access modifier on method 'doWork()' - 🟡 `pmd:MissingSerialVersionUID` L1359 Classes implementing Serializable should set a serialVersionUID - 🟡 `pmd:AtLeastOneConstructor` L1359 Each class should declare at least one constructor - 🟡 `pmd:UnusedPrivateField` L1360 Avoid unused private fields such as 'value'. - 🟡 `pmd:AtLeastOneConstructor` L1364 Each class should declare at least one constructor - 🟡 `pmd:UnusedPrivateField` L1366 Avoid unused private fields such as 'nonSerializableField'. - 🟡 `pmd:ImmutableField` L1366 Field 'nonSerializableField' may be declared final - 🟡 `pmd:PublicMemberInNonPublicType` L1378 Public member 'getInstance' declared in a non-public type - 🟡 `pmd:PublicMemberInNonPublicType` L1390 Public member 'getInstance' declared in a non-public type - 🟡 `pmd:NonThreadSafeSingleton` L1391 单例实现不是线程安全的 建议: 使用 enum 单例、静态持有者（holder）或双重检查加 volatile。 - 🔵 `pmd:UnnecessaryFullyQualifiedName` L402 不必要使用全限定名 建议: 使用已导入的简单类名代替全限定名。 - 🔵 `pmd:DoNotThrowExceptionInFinally` L727 在 finally 块中抛出异常会使控制流难以理解 建议: 不要在 finally 中抛出异常，先记录或吞掉 finally 中的异常。 - 🔵 `pmd:InstantiationToGetClass` L801 不要仅为获取 Class 对象而实例化 建议: 使用 Integer.class 而不是 new Integer(1).getClass()。 - 🔵 `pmd:StringBufferInstantiationWithChar` L904 new StringBuffer(char) 会把 char 隐式转为 int 容量 建议: 使用 new StringBuffer() 或 new StringBuffer("c") 明确意图。 - 🔵 `pmd:InvalidLogMessageFormat` L1112 日志消息格式参数数量不匹配 建议: 修正占位符数量：一个 {} 对应一个参数。 - 🔵 `pmd:InvalidLogMessageFormat` L1113 Too many arguments, expected 1 argument but found 2 - 🔵 `pmd:UnnecessaryFullyQualifiedName` L1184 Unnecessary qualifier 'java.io': 'Serializable' is already in scope because it is imported in this file AI 审查 · 9 条建议 - 🔴 [AI] [bug] `rethrow-missing-throws` L48 **捕获 IOException 后重新抛出但方法未声明 throws IOException，编译失败** ReThrow.bad() 中 catch (IOException e) 后直接 throw e，但 bad() 没有 throws IOException，无法编译。 建议: 在方法签名上增加 throws IOException，或者更简单：不要捕获该异常，直接让 doWork() 的异常向外传播。 - 🔴 [AI] [bug] `wrap-same-missing-throws` L61 **包装 IOException 抛出但方法未声明 throws IOException，编译失败** WrapSame.bad() 中 catch 后 throw new IOException(...)，但 bad() 未声明 throws IOException，代码无法编译。 建议: 为 bad() 增加 throws IOException，或捕获后改为抛出一个非受检异常。 - 🔴 [AI] [bug] `finalize-protected-inaccessible` L565 **显式调用 Object.finalize() 违反访问控制，无法编译** CallFinalize.bad() 中通过 Object 引用调用 o.finalize()，但 Object.finalize() 是 protected 方法，不在同包且不是通过子类引用访问，编译不通过。 建议: 删除该调用；如果需要清理资源，使用 AutoCloseable/Cleaner。 - 🔴 [AI] [bug] `null-inputstream-skip-npe` L637 **InputStream 初始化为 null 后直接调用 skip()，必现 NPE** CheckSkip.bad() 中 InputStream in = null，随后调用 in.skip(10)，运行时必然抛出 NullPointerException。 建议: 初始化真实流，并用 try-with-resources 管理生命周期，同时检查 skip 返回值。 - 🔴 [AI] [performance] `infinite-loop-inner-increment` L1133 **内层循环误递增外层变量 i，且 k 永不变，导致无限循环** JumbledInc.foo() 的内层循环 for (int k = 0; k < 20; i++) 更新的是 i 而不是 k，k 恒为 0，内层循环永不退出，程序将挂起。 建议: 内层循环应递增自己的控制变量 k。 - 🟡 [AI] [design] `bean-getter-setter-naming` L317 **getter/setter 未遵循 JavaBean 命名规范，影响框架绑定** BadBean 中 getname/setname 不符合 JavaBean 规范，应为 getName/setName，否则很多序列化/绑定框架无法识别。 建议: 将 getter 改为 getName()，setter 改为 setName(String name)。 - 🟡 [AI] [security] `singleton-cast-classcastexception` L1039 **重载 getInstance(Object) 中无类型检查直接强转，会抛 ClassCastException** SingletonDemo.getInstance(Object obj) 直接 (SingletonDemo) obj，传入非 SingletonDemo 对象时抛出 ClassCastException，且该重载破坏了单例语义。 建议: 删除该重载方法；如果确需接收对象，应先 instanceof 校验后再处理。 - 🟡 [AI] [bug] `log-exception-as-string` L1101 **日志只输出异常的 toString，丢失堆栈信息** CorrectLog.bar() 中 _LOG.error(String.valueOf(e)) 只记录异常字符串，无法看到堆栈；应把异常对象作为最后一个参数传给日志 API。 建议: 使用 _LOG.error("doWork failed", e)，保留异常堆栈。 - 🟡 [AI] [bug] `loop-break-on-first-iteration` L1222 **循环第一次迭代就 break，后续逻辑成为死代码** BranchLastInLoop.foo() 中 if (i > 25) 永远不成立（i 最大为 9），而循环体末尾的 break 无条件执行，导致循环只执行一次。 建议: 检查循环终止条件，删除多余的 break，或把 break 放入有意义的条件判断中。