以往在使用异常时，只是知道通过异常类的构造方法设置一些出错信息,此外最多就是把引起该异常的原因通过Throwable类的子类一同设置进去。今天在分析springSecurity3.0.5的框架时，看到AuthenticationException这个异常类(用在验证时)的源码，发现这个异常类除了上述常见的用法外，还把Authentication（验证信息）的做为属性放到了异常类中，当验证出错时AuthenticationException抛出时，Authentication（验证信息）一同被抛出了，这样捕获异常的类就能得到更丰富的信息，有些数据还可以通过异常类返回给调用者。看了这样的代码，思路不由地开阔了不少。该类源码如下：
1 package org.springframework.security.core;
2
3 /** 4 * Abstract superclass for all exceptions related to an {@link Authentication} object being invalid for whatever 5 * reason. 6 * 7 * @author Ben Alex 8 */ 9 public abstract class AuthenticationException extends RuntimeException { 10 //~ Instance fields ================================================================================================ 11 12 private Authentication authentication; 13 private Object extraInformation; 14 15 //~ Constructors =================================================================================================== 16 17 /** 18 * Constructs an <code>AuthenticationException</code> with the specified message and root cause. 19 * 20 * @param msg the detail message 21 * @param t the root cause 22 */ 23 public AuthenticationException(String msg, Throwable t) { 24 super(msg, t); 25 } 26 27 /** 28 * Constructs an <code>AuthenticationException</code> with the specified message and no root cause. 29 * 30 * @param msg the detail message 31 */ 32 public AuthenticationException(String msg) { 33 super(msg); 34 } 35 36 public AuthenticationException(String msg, Object extraInformation) { 37 super(msg); 38 this.extraInformation = extraInformation; 39 } 40 41 //~ Methods ======================================================================================================== 42 43 /** 44 * The authentication request which this exception corresponds to (may be <code>null</code>) 45 */ 46 public Authentication getAuthentication() { 47 return authentication; 48 } 49 50 public void setAuthentication(Authentication authentication) { 51 this.authentication = authentication; 52 } 53 54 /** 55 * Any additional information about the exception. Generally a <code>UserDetails</code> object. 56 * 57 * @return extra information or <code>null</code> 58 */ 59 public Object getExtraInformation() { 60 return extraInformation; 61 } 62 63 public void clearExtraInformation() { 64 this.extraInformation = null; 65 } 66 }
下面是在AbstractAuthenticationManager类中被使用到的片断：
public
final
Authentication authenticate(Authentication authRequest)
throws
AuthenticationException {
try
{
return
doAuthentication(authRequest);
}
catch
(AuthenticationException e) {
e.setAuthentication(authRequest);
if
(clearExtraInformation) {
e.clearExtraInformation();
}
throw
e;
}
}
|
通过上述两段源码可以看到，老外在写代码时考虑得很细，在异常类中加入了额外信息后,还提供了一个 clearExtraInformation()方法，用来清除额外信息。
转：https://www.cnblogs.com/hzhuxin/archive/2011/12/12/2285101.html
以往在使用异常时，只是知道通过异常类的构造方法设置一些出错信息,此外最多就是把引起该异常的原因通过Throwable类的子类一同设置进去。今天在分析springSecurity3.0.5的框架时，看到AuthenticationException这个异常类(用在验证时)的源码，发现这个异常类除了上述常见的用法外，还把Authentication（验证信息）的做为属性放到了异常类中，当验证出错时AuthenticationException抛出时，Authentication（验证信息）一同被抛出了，这样捕获异常的类就能得到更丰富的信息，有些数据还可以通过异常类返回给调用者。看了这样的代码，思路不由地开阔了不少。该类源码如下：
1 package org.springframework.security.core;
2
3 /** 4 * Abstract superclass for all exceptions related to an {@link Authentication} object being invalid for whatever 5 * reason. 6 * 7 * @author Ben Alex 8 */ 9 public abstract class AuthenticationException extends RuntimeException { 10 //~ Instance fields ================================================================================================ 11 12 private Authentication authentication; 13 private Object extraInformation; 14 15 //~ Constructors =================================================================================================== 16 17 /** 18 * Constructs an <code>AuthenticationException</code> with the specified message and root cause. 19 * 20 * @param msg the detail message 21 * @param t the root cause 22 */ 23 public AuthenticationException(String msg, Throwable t) { 24 super(msg, t); 25 } 26 27 /** 28 * Constructs an <code>AuthenticationException</code> with the specified message and no root cause. 29 * 30 * @param msg the detail message 31 */ 32 public AuthenticationException(String msg) { 33 super(msg); 34 } 35 36 public AuthenticationException(String msg, Object extraInformation) { 37 super(msg); 38 this.extraInformation = extraInformation; 39 } 40 41 //~ Methods ======================================================================================================== 42 43 /** 44 * The authentication request which this exception corresponds to (may be <code>null</code>) 45 */ 46 public Authentication getAuthentication() { 47 return authentication; 48 } 49 50 public void setAuthentication(Authentication authentication) { 51 this.authentication = authentication; 52 } 53 54 /** 55 * Any additional information about the exception. Generally a <code>UserDetails</code> object. 56 * 57 * @return extra information or <code>null</code> 58 */ 59 public Object getExtraInformation() { 60 return extraInformation; 61 } 62 63 public void clearExtraInformation() { 64 this.extraInformation = null; 65 } 66 }
下面是在AbstractAuthenticationManager类中被使用到的片断：
public
final
Authentication authenticate(Authentication authRequest)
throws
AuthenticationException {
try
{
return
doAuthentication(authRequest);
}
catch
(AuthenticationException e) {
e.setAuthentication(authRequest);
if
(clearExtraInformation) {
e.clearExtraInformation();
}
throw
e;
}
}
|
通过上述两段源码可以看到，老外在写代码时考虑得很细，在异常类中加入了额外信息后,还提供了一个 clearExtraInformation()方法，用来清除额外信息。
转：https://www.cnblogs.com/hzhuxin/archive/2011/12/12/2285101.html