Spring boot異常統一處理方法：@ControllerAdvice註解的使用、全局異常捕獲、自定義異常捕獲

1、全局異常

一、首先建立異常處理包和類

二、使用@ControllerAdvice註解，全局捕獲異常類，只要做用在@RequestMapping上，全部的異常都會被捕獲

package com.example.demo.exception; import org.springframework.web.bind.annotation.ControllerAdvice; import org.springframework.web.bind.annotation.ExceptionHandler; import org.springframework.web.bind.annotation.ResponseBody; import java.util.HashMap; import java.util.Map; /** * 全局捕獲異常類，只要做用在@RequestMapping上，全部的異常都會被捕獲 */ @ResponseBody @ControllerAdvice public class MyControllerAdvice { @ExceptionHandler(value = Exception.class) public Map<String,Object> errorHandle(Exception e){ Map<String,Object> map = new HashMap<String,Object>(); map.put("code",-1); map.put("msg",e.getMessage()); return map; } }

　　這上面有個須要注意的是要加上@ResponseBody註解，若是不加會怎麼樣呢，咱們試下，報錯：

javax.servlet.ServletException: Circular view path [hello]: would dispatch back to the current handler URL [/hello] again. 
Check your ViewResolver setup! (Hint: This may be the result of an unspecified view, due to default view name generation.) at org.springframework.web.servlet.view.InternalResourceView.prepareForRendering(InternalResourceView.java:209) ~[spring-webmvc-5.0.6.RELEASE.jar:5.0.6.RELEASE] at org.springframework.web.servlet.view.InternalResourceView.renderMergedOutputModel(InternalResourceView.java:147) ~[spring-webmvc-5.0.6.RELEASE.jar:5.0.6.RELEASE] at org.springframework.web.servlet.view.AbstractView.render(AbstractView.java:314) ~[spring-webmvc-5.0.6.RELEASE.jar:5.0.6.RELEASE] at org.springframework.web.servlet.DispatcherServlet.render(DispatcherServlet.java:1325) ~[spring-webmvc-5.0.6.RELEASE.jar:5.0.6.RELEASE] at org.springframework.web.servlet.DispatcherServlet.processDispatchResult(DispatcherServlet.java:1069) ~[spring-webmvc-5.0.6.RELEASE.jar:5.0.6.RELEASE] at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1008) ~[spring-webmvc-5.0.6.RELEASE.jar:5.0.6.RELEASE] at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:925) ~[spring-webmvc-5.0.6.RELEASE.jar:5.0.6.RELEASE] at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:974) ~[spring-webmvc-5.0.6.RELEASE.jar:5.0.6.RELEASE] at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:866) ~[spring-webmvc-5.0.6.RELEASE.jar:5.0.6.RELEASE] at javax.servlet.http.HttpServlet.service(HttpServlet.java:635) ~[tomcat-embed-core-8.5.31.jar:8.5.31] at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:851) ~[spring-webmvc-5.0.6.RELEASE.jar:5.0.6.RELEASE] at javax.servlet.http.HttpServlet.service(HttpServlet.java:742) ~[tomcat-embed-core-8.5.31.jar:8.5.31] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231) ~[tomcat-embed-core-8.5.31.jar:8.5.31]

　　由於是個json的格式，因此必需要有@ResponseBody

三、測試：在hello裏面造個異常

package com.example.demo; import org.springframework.beans.factory.annotation.Value; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RestController; @RestController public class HelloController { @Value("${gwf.name}") private String msg; @RequestMapping("/hello") public String hello() { int num = 1/0; return this.msg; } }

　　結果：

2、自定義異常

一、首先建立自定義異常類：注意須要繼承extends RuntimeException

package com.example.demo.exception; public class BusinessException extends RuntimeException{ private String code; private String msg; public BusinessException(String code, String msg) { super(); this.code = code; this.msg = msg; } public String getCode() { return code; } public void setCode(String code) { this.code = code; } public String getMsg() { return msg; } public void setMsg(String msg) { this.msg = msg; } }

　　這裏介紹下idea自動生成get/set和構造函數的快捷鍵：alt + insert，而後選擇getter和setter，constructor，自動生成get、set方法和構造函數

二、而後就是自定義異常捕獲

package com.example.demo.exception; import org.springframework.web.bind.annotation.ControllerAdvice; import org.springframework.web.bind.annotation.ExceptionHandler; import org.springframework.web.bind.annotation.ResponseBody; import java.util.HashMap; import java.util.Map; /** * 全局捕獲異常類，只要做用在@RequestMapping上，全部的異常都會被捕獲 */ @ResponseBody @ControllerAdvice public class MyControllerAdvice { @ExceptionHandler(value = Exception.class) public Map<String,Object> errorHandle(Exception e){ Map<String,Object> map = new HashMap<String,Object>(); map.put("code",-1); map.put("msg",e.getMessage()); return map; } @ExceptionHandler(value = BusinessException.class) public Map<String,Object> errorHandle(BusinessException e){ Map<String,Object> map = new HashMap<String,Object>(); map.put("code",e.getCode()); map.put("msg",e.getMsg()); return map; } }

三、最後咱們測試下：拋出自定義異常

package com.example.demo; import com.example.demo.exception.BusinessException; import org.springframework.beans.factory.annotation.Value; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RestController; @RestController public class HelloController { @Value("${gwf.name}") private String msg; @RequestMapping("/hello") public String hello() { //int num = 1/0;
        throw new BusinessException("100","密碼錯誤"); //return this.msg;
 } }

　　結果：