Vert.x 4 Web 应用异常全局统一拦截处理

编程教程 > Java > Vert.x (332) 2024-11-26 14:39:04

前言

引用之前的例子《Vert.x 4 Web REST CRUD接口应用》项目作为基础进行修改，创建一个自定义异常和异常拦截处理器。以实现

对指定异常返回特殊数据
对未指定异常返回通用错误

项目结构参考

Vert.x 4 Web 应用异常全局统一拦截处理_图示-4c0c9ad7e437488382b0008af62aef46.png

基于上一篇项目用到的类，新增了红色圈出来的类。

引入开发工具组件`lombok`

maven pom.xml 依赖模块添加以下依赖：

<dependency>
  <groupId>org.projectlombok</groupId>
  <artifactId>lombok</artifactId>
  <optional>true</optional>
  <version>1.18.34</version>
</dependency>

新增自定义异常`BusinessException`

@EqualsAndHashCode(callSuper = true)
@Data
public class BusinessException extends RuntimeException{
  private int code=480;
  private String msg;


  public BusinessException() {
    this.msg="未知错误或空指针";
  }

  public BusinessException(int code, String msg) {
    this.code = code;
    this.msg = msg;
  }

  public BusinessException(String message) {
    super(message);
    this.msg=message;
  }

  public BusinessException(String message, Throwable cause) {
    super(message, cause);
    this.msg=message;
  }

  public BusinessException(Throwable cause) {
    super(cause);
    this.msg=cause.getMessage();
  }

  public BusinessException(String message, Throwable cause, boolean enableSuppression, boolean writableStackTrace) {
    super(message, cause, enableSuppression, writableStackTrace);
    this.msg=message;
  }


}

创建异常处理器`DefaultExceptionHandler`

public class DefaultExceptionHandler implements Handler<RoutingContext> {

  public DefaultExceptionHandler() {

  }

  @Override
  public void handle(RoutingContext routingContext) {
    Throwable throwable = routingContext.failure();
    if (throwable == null) {
      routingContext.response()
        .setStatusCode(200)
        .putHeader("content-type", "application/json; charset=utf-8")
        .end(Json.encodeToBuffer(Result.fail(480,"未知错误")));
      return;
    }

    if (throwable instanceof NullPointerException) {
      routingContext.response()
        .setStatusCode(200)
        .putHeader("content-type", "application/json; charset=utf-8")
        .end(Json.encodeToBuffer(Result.fail(480,"空指针")));
    }

    if (throwable instanceof BusinessException businessException) {
      routingContext.response()
        .setStatusCode(200)
        .putHeader("content-type", "application/json; charset=utf-8")
        .end(Json.encodeToBuffer(Result.fail(businessException.getCode(), businessException.getMsg())));
      return;
    }
    //其他没有指明的统一输出500
    routingContext.response()
      .setStatusCode(200)
      .putHeader("content-type", "application/json; charset=utf-8")
      .end(Json.encodeToBuffer(Result.fail(500, "系统内部错误")));

  }

  public static DefaultExceptionHandler of() {
    return new DefaultExceptionHandler();
  }
}

在路由处引入拦截器

聚焦代码

//必须加 last()排序到最后兜底
router.route().last().failureHandler(DefaultExceptionHandler.of());

编辑get 接口实现

/**
 * 通过路径参数id获取单个产品
 * @param routingContext 路由上下文
 */
private void getById(RoutingContext routingContext){
  String id = routingContext.pathParam("id");
  Whisky whisky = products.get(Integer.parseInt(id));
  if (whisky == null) {
    throw new BusinessException(481,"未找到相关产品信息：id-"+id);
  }
  routingContext.response()
    .putHeader("content-type", "application/json; charset=utf-8")
    .end(Json.encodePrettily(whisky));
}