本文已参与「新人创作礼」活动，一起开启掘金创作之路。
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' |
