【持续更新】Java 中使用 @SuppressWarnings 警告压制汇总

根据个人实际代码中遇到的警告问题进行汇总，持续更新。

通过 @SuppressWarnings(“关键字”) 进行抑制警告，一般我们对警告的处理是要么抑制要么修复。

标准用法

一般常用在普通 JavaSE 项目中。

关键字	用途
all	to suppress all warnings
boxing	to suppress warnings relative to boxing/unboxing operations
cast	to suppress warnings relative to cast operations
dep-ann	to suppress warnings relative to deprecated annotation
deprecation	to suppress warnings relative to deprecation
fallthrough	to suppress warnings relative to missing breaks in switch statements
finally	to suppress warnings relative to finally block that don’t return
hiding	to suppress warnings relative to locals that hide variable
incomplete-switch	to suppress warnings relative to missing entries in a switch statement (enum case)
nls	to suppress warnings relative to non-nls string literals
null	to suppress warnings relative to null analysis
rawtypes	to suppress warnings relative to un-specific types when using generics on class params
restriction	to suppress warnings relative to usage of discouraged or forbidden references
serial	to suppress warnings relative to missing serialVersionUID field for a serializable class
static-access	o suppress warnings relative to incorrect static access
synthetic-access	to suppress warnings relative to unoptimized access from inner classes
unchecked	to suppress warnings relative to unchecked operations
unqualified-field-access	to suppress warnings relative to field access unqualified
unused	to suppress warnings relative to unused code

idea

idea 给普通 JavaSE 提供的语法警告。

关键字	用途
UnnecessaryLocalVariable	Local variable ‘userId’ is redundant
FieldCanBeLocal	Field can be converted to a local variable

个人觉得 Local variable ‘xxx’ is redundant 这种提示你做 inline 处理的其实没必要进行 inline，就 debug （不用点进去再勾选方法结束，勾选易卡顿）和可读性而言我个人是不喜欢做 inline 处理的。由于还存在 javac 编译时优化，源码上多一个变量，编译后执行也不会有性能问题，因此可以关闭 idea 的警告。

Spring

idea 在 Spring 以及 SpringBoot 等 Spring 的衍生项目中提供的语法警告。

关键字	用途
SpringJavaInjectionPointsAutowiringInspection	Could not autowire. No beans of ‘XXX’ type found.
SpringJavaAutowiredFieldsWarningInspection	Field injection is not recommended
ConfigurationProperties	Not registered via @EnableConfigurationProperties or marked as Spring component
@SuppressWarnings(“ConstantConditions”)	Condition ‘xxx != null’ is always ‘true’