cas4.0.0中cas-server登录页自定义提示消息实现方法

网上关于cas4.0.0版本的文章比较少，公司需要验证用户信息账号密码是否正确，长度限制等并提示关于对象的错误信息提示，因此本站总结了关于如何自定义cas4.0.0验证登录时错误提示消息，对于cas-server登录页登录时自定义提示消息的实现方法有什么疑问，在本站素文宅blog.yoodb.com中留言即可。

cas4实现自定义验证登录提示错误信息，具体步骤配置

1、首先在cas-server-core工程中新建PasswordAuthenticationException.java类，代码如下：

package org.jasig.cas.authentication.handler;

public class PasswordAuthenticationException extends
java.security.GeneralSecurityException {
private static final long serialVersionUID = 1L;

/**
     * Constructs a PasswordAuthenticationException with no detail message.
     * A detail message is a String that describes this particular exception.
     */
    public PasswordAuthenticationException() {
        super();
    }

    /**
     * Constructs a PasswordAuthenticationException with the specified
     * detail message. A detail message is a String that describes
     * this particular exception.
     *
     * <p>
     *
     * @param msg the detail message.
     */
    public PasswordAuthenticationException(String msg) {
        super(msg);
    }

}

2、修改验证错误返回异常提示AuthenticationExceptionHandler.java类，具体代码如下：

static {
        DEFAULT_ERROR_LIST.add(javax.security.auth.login.AccountLockedException.class);
        DEFAULT_ERROR_LIST.add(javax.security.auth.login.FailedLoginException.class);
        DEFAULT_ERROR_LIST.add(javax.security.auth.login.CredentialExpiredException.class);
        DEFAULT_ERROR_LIST.add(javax.security.auth.login.AccountNotFoundException.class);
        DEFAULT_ERROR_LIST.add(org.jasig.cas.authentication.AccountDisabledException.class);
        DEFAULT_ERROR_LIST.add(org.jasig.cas.authentication.InvalidLoginLocationException.class);
        DEFAULT_ERROR_LIST.add(org.jasig.cas.authentication.InvalidLoginTimeException.class);
        /*----新增--------*/
        DEFAULT_ERROR_LIST.add(org.jasig.cas.authentication.handler.PasswordAuthenticationException.class);
    }

3、修改抽象用户密码验证AbstractUsernamePasswordAuthenticationHandler.java类，具体代码如下：

@Override
protected final HandlerResult doAuthentication(final Credential credential)
    throws GeneralSecurityException, PreventedException {
final UsernamePasswordCredential userPass = (UsernamePasswordCredential) credential;
if (userPass.getUsername() == null || userPass.getUsername().equals("")) {
   throw new AccountNotFoundException("Username is null.(blog.yoodb.com)");
}

final String transformedUsername= this.principalNameTransformer.transform(userPass.getUsername());
if (transformedUsername == null || transformedUsername.equals("")) {
   throw new AccountNotFoundException("Transformed username is null.");
}
/*----新增（简单例子）--------*/
if(8 < password.length()){
   throw new PasswordAuthenticationException("password is too long ---(blog.yoodb.com)");
}
userPass.setUsername(transformedUsername);
return authenticateUsernamePasswordInternal(userPass);
}

4、在login-webflow.xml配置文件中增加关于PasswordAuthenticationException类配置，具体配置代码如下：

<action-state id="handleAuthenticationFailure">
    <evaluate expression="authenticationExceptionHandler.handle(currentEvent.attributes.error, messageContext)" />
    <transition on="AccountDisabledException" to="casAccountDisabledView"/>
    <transition on="AccountLockedException" to="casAccountLockedView"/>
    <transition on="CredentialExpiredException" to="casExpiredPassView"/>
    <transition on="InvalidLoginLocationException" to="casBadWorkstationView"/>
    <transition on="InvalidLoginTimeException" to="casBadHoursView"/>
    <transition on="FailedLoginException" to="generateLoginTicket"/>
    <transition on="AccountNotFoundException" to="generateLoginTicket"/>
    <transition on="PasswordAuthenticationException" to="generateLoginTicket"/>
    <transition on="UNKNOWN" to="generateLoginTicket"/>
  </action-state>

5、在messages.properties文件中增加提示信息，具体信息如下：

authenticationFailure.PasswordAuthenticationException=密码超出限制范围

分析：步骤3新增代码DEFAULT_ERROR_LIST.add(org.jasig.cas.authentication.handler.PasswordAuthenticationException.class);是为了之后代码中判断返回class异常类是否有匹配项，存在后判断会生成authenticationFailure.PasswordAuthenticationException字符串，通过读取messages.properties文件获取错误提示信息。