完整项目地址:micro-service-plus
系列文章入口:
前言
主要介绍@RestControllerAdvice捕捉全局异常,然后返回给前端显示
我们这边主要以ty-example为例进行说明
注:micro-service-plus里的微服务都会引用ty-common里的配置和依赖
核心文件介绍
ty-common/khcomomon/exception/BaseExceptionHandler
/*
* 全局异常处理
* */
//@RestControllerAdvice 捕捉当前微服务里的错误,并将错误信息返回前端
@RestControllerAdvice
public class BaseExceptionHandler {
//方法参数传入移除监听,如果传入的方法和参数有问题,直接return回前端
@ExceptionHandler(MethodArgumentNotValidException.class)
public ResResult MethodArgumentNotValidExceptionHandler(MethodArgumentNotValidException e) {
ObjectError objectError = e.getBindingResult().getAllErrors().get(0);
return new ResResult().error(objectError.getDefaultMessage());
}
//微服务异常监听,如果微服务中产生Exception相关的异常(包括RunTimeException),直接return回前端
@ExceptionHandler(value = Exception.class)
public ResResult error(Exception e) {
e.printStackTrace();
return new ResResult().error(e.getMessage());
}
}
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在ty-example中的config/BaseConfig
/*
* 总结:1.@Configuration 下的@ComponentScan回将包下带有@Component扫描变成配置类,
* 而@SpringBootApplication扫描的只会变成普通类
* */
@Configuration
@ComponentScan(basePackages = {"top.kuanghua.khcomomon"})
//mapper scanning
@MapperScan(basePackages = {"top.kuanghua.tyexample.mapper"})
//feign scanning
@EnableFeignClients(basePackages = {"top.kuanghua.feign"})
public class BaseConfig {
}
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@ComponentScan(basePackages = {"top.kuanghua.khcomomon"})
会将ty-common/khcomomon下的配置
全部都扫进来,包括全局异常处理配置(BaseExceptionHandler),mybitsPlusConfig基本配置(MybatisPlusConfig),swagger基本配置等
注:在每个微服务中都有BaseConfig文件,用于通用基本配置,,包括全局异常处理配置(BaseExceptionHandler),mybitsPlusConfig基本配置(MybatisPlusConfig),swagger基本配置等
现在已经将BaseExceptionHandler导入到项目了,那么如何更优雅的使用它呢?
我们看一段代码
ty-example/service/UploadService
//检验文件内容
BufferedImage bufferedImage = ImageIO.read(file.getInputStream());
if (bufferedImage == null) {
log.info("文件不能为空:{}", originalFilename);
throw new RuntimeException("文件不能为空");
}
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throw new RuntimeException("文件内容不合法"); 这段代码写在service中,但是BaseExceptionHandler将会进行捕捉直接返回前端,不用再controller层自己处理。所以以后有啥异常想直接返回告诉前端就用throw new RuntimeException。省了很多事情
前端收到的内容如下:
{flag: false, code: 20001, msg: "文件不能为空", data: null}
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因此你以后在service,不用写太多处理错误的逻辑,也不用写返回前端的代码逻辑,直接写一个throw new RuntimeException("文件不能为空"),就行了
通用返回类ResResult
ty-common\src\main\java\top\kuanghua\khcomomon\entity\ResResult.java
@Data
@AllArgsConstructor
public class ResResult<T> implements Serializable {
private static final long serialVersionUID = 2344775856369318037L;
private boolean flag;//是否成功
private Integer code;//返回码
private String msg;//返回消息
private T data;//返回数据
//成功返回可传入data
public ResResult success(Object data) {
this.flag = true;
this.code = StatusCode.OK;
this.data = (T) data;
return this;
}
//成功返回
public ResResult success() {
this.flag = true;
this.code = StatusCode.OK;
this.msg = "操作成功!";
return this;
}
//失败返回可传入msg
public ResResult error(String msg) {
this.flag = false;
this.code = StatusCode.ERROR;
this.msg = msg;
return this;
}
//失败返回可传入msg和data
public ResResult(String msg, Object data) {
this.flag = true;
this.code = StatusCode.OK;
this.msg = msg;
this.data = (T) data;
}
public ResResult(boolean flag, Integer code, String msg) {
this.flag = flag;
this.code = code;
this.msg = msg;
}
public ResResult() {
this.flag = true;
this.code = StatusCode.OK;
this.msg = "操作成功!";
}
}
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如何使用
//成功
@GetMapping("sendEmailText")
public ResResult sendEmailText() {
return new ResResult().success("发送邮件成功");
}
//失败
return new ResResult().error(e.getMessage());
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