有的时候，为了保全代码的简洁，我们不希望在程序中看到一些跟程序逻辑的代码，譬如异常日志打印，这个时候就需要我们对程序中的异常日志进行统一的管理。spring aop 可以在不破坏程序逻辑的情况下很好的完成我们上面的需求。本文对对日志的处理使用到了ThrowsAdvice接口和spring aop
ThrowsAdvice接口
1 /*
2 * Copyright 2002-2008 the original author or authors.
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 package org.springframework.aop;
18
19 /**
20 * Tag interface for throws advice.
21 *
22 * <p>There are not any methods on this interface, as methods are invoked by
23 * reflection. Implementing classes must implement methods of the form:
24 *
25 * <pre class="code">void afterThrowing([Method, args, target], ThrowableSubclass);</pre>
26 *
27 * <p>Some examples of valid methods would be:
28 *
29 * <pre class="code">public void afterThrowing(Exception ex)</pre>
30 * <pre class="code">public void afterThrowing(RemoteException)</pre>
31 * <pre class="code">public void afterThrowing(Method method, Object[] args, Object target, Exception ex)</pre>
32 * <pre class="code">public void afterThrowing(Method method, Object[] args, Object target, ServletException ex)</pre>
33 *
34 * The first three arguments are optional, and only useful if we want further
35 * information about the joinpoint, as in AspectJ <b>after-throwing</b> advice.
36 *
37 * <p><b>Note:</b> If a throws-advice method throws an exception itself, it will
38 * override the original exception (i.e. change the exception thrown to the user).
39 * The overriding exception will typically be a RuntimeException; this is compatible
40 * with any method signature. However, if a throws-advice method throws a checked
41 * exception, it will have to match the declared exceptions of the target method
42 * and is hence to some degree coupled to specific target method signatures.
43 * <b>Do not throw an undeclared checked exception that is incompatible with
44 * the target method‘s signature!</b>
45 *
46 * @author Rod Johnson
47 * @author Juergen Hoeller
48 * @see AfterReturningAdvice
49 * @see MethodBeforeAdvice
50 */
51 public interface ThrowsAdvice extends AfterAdvice {
52
53 }
看接口说明可知，该接口上没有任何方法，但是实现了这个接口的类必须至少实现以下4个方法中的一个，否则程序报：
Caused by: java.lang.IllegalArgumentException: At least one handler method must be found in class
接口中的异常类可以为自己自定义的异常类，方法是通过反射调用。
1 public void afterThrowing(Exception ex) 2 public void afterThrowing(RemoteException) 3 public void afterThrowing(Method method, Object[] args, Object target, Exception ex) 4 public void afterThrowing(Method method, Object[] args, Object target, ServletException ex)
自定义异常类
1 package com.apt.study.exception;
2
3 public class StudyException extends RuntimeException {
4
5 /**
6 *
7 */
8 private static final long serialVersionUID = -6183216129830888521L;
9
10 /**
11 * 异常信息
12 */
13 protected String message;
14
15 /**
16 * 异常编码
17 */
18 protected int code;
19
20 public static final StudyException PARAM_VALIDATE_EXCEPTION = new StudyException(1234,"参数校验出错");
21
22 public StudyException(int code, String msgFormat, Object... args) {
23 super(String.format(msgFormat, args));
24 this.code = code;
25 this.message = String.format(msgFormat, args);
26 }
27
28 public StudyException(String message, Throwable cause) {
29 super(message, cause);
30 }
31
32 public StudyException(Throwable cause) {
33 super(cause);
34 }
35
36 public StudyException(String message) {
37 super(message);
38 }
39
40 public String getMessage() {
41 return message;
42 }
43
44 public void setMessage(String message) {
45 this.message = message;
46 }
47
48 public int getCode() {
49 return code;
50 }
51
52 public void setCode(int code) {
53 this.code = code;
54 }
55
56
57 }
异常日志处理类
1 package com.apt.study.exception;
2
3 import java.lang.reflect.Method;
4
5 import org.slf4j.Logger;
6 import org.slf4j.LoggerFactory;
7 import org.springframework.aop.ThrowsAdvice;
8
9 public class ExceptionLogHandler implements ThrowsAdvice{
10
11 public Logger logger = LoggerFactory.getLogger(ExceptionLogHandler.class);
12
13 public void afterThrowing(Method method, Object[] args, Object target, StudyException ex) {
14 logger.error("ExceptionLogHandler--StudyExcception");
15 logger.info("-------errCode:" + ex.getCode() + "; errMessage:" + ex.getMessage());
16 errorClassInfo(ex);
17 logger.info("-------" + ex.fillInStackTrace());
18 }
19
20 public void afterThrowing(Method method, Object[] args, Object target, Exception ex) {
21
22 logger.error("ExceptionLogHandler--Exception");
23 logger.error("------->Erro Class: "+ target.getClass().getName());
24 logger.error("------->Error method:"+ method.getName());
25
26 if(args != null) {
27 for(int i=0; i<args.length; i++) {
28 logger.error("------->args[" + i + "]: " + args[i]);
29 }
30 }
31
32 logger.error("------->Exception class: " + ex.getClass().getName());
33 errorClassInfo(ex);
34 logger.error("------->" + ex.fillInStackTrace());
35 }
36
37 //打印抛出异常地方的信息
38 private void errorClassInfo(Exception ex) {
39 /*
40 * ex.getStackTrace()返回堆栈跟踪元素的数组，每个元素表示一个堆栈帧。数组的第零个元素（假定数据的长度为非零）表示堆栈顶部，
41 * 它是序列中最后的方法调用。
42 * 通常，这是创建和抛出该 throwable 的地方。数组的最后元素（假定数据的长度为非零）表示堆栈底部，它是序列中第一个方法调用
43 */
44 StackTraceElement[] stackTraceElementArr= ex.getStackTrace();
45 StackTraceElement stackTraceElement = stackTraceElementArr[0];
46 logger.error("------->Erro File:" + stackTraceElement.getFileName());
47 logger.error("------->Erro Method:" + stackTraceElement.getMethodName());
48 logger.error("------->Erro Line:" + stackTraceElement.getLineNumber());
49 }
50
51 }
spring-context.xml 配置
<!-- 异常信息 拦截 -->
<bean id="exceptionLog" class="com.apt.study.exception.ExceptionLogHandler"></bean>
<aop:config>
<aop:pointcut id="exceptionTrade" expression="execution(* com.apt.study.service.*.*(..))" />
<aop:advisor pointcut-ref="exceptionTrade" advice-ref="exceptionLog"/>
</aop:config>
时间： 2024-10-15 06:13:31