spring security登录成功后跳转回登录前的页面

.successhandler(new AuthenticationSuccessHandler() {            
            @Override
            public void onAuthenticationSuccess(httpservletRequest request, HttpServletResponse response,
                    Authentication authentication) throws IOException, ServletException {
              response.setContentType("application/JSON;charset=utf-8");
 
              RequestCache cache = new HttpSessionRequestCache();
              SavedRequest savedRequest = cache.getRequest(request, response);
              String url = savedRequest.getRedirectUrl();              
              response.sendRedirect(url);           
            }
        })

<?xml version="1.0" encoding="UTF-8"?>
<beans:beans xmlns="http://www.springframework.org/schema/security"
	xmlns:beans="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
						http://www.springframework.org/schema/security http://www.springframework.org/schema/security/spring-security.xsd">
	<!--配置不用拦截的资源-->
	<http pattern="/*.html" security="none"></http>
	<http pattern="/CSS/**" security="none"></http>
	<http pattern="/img/**" security="none"></http>
	<http pattern="/js/**" security="none"></http>
	<http pattern="/plugins/**" security="none"></http>
	<!-- 页面的拦截规则 -->
	<http use-expressions="false">
		<intercept-url pattern="/**" access="ROLE_ADMIN"/>
		<form-login login-page="/login.html" default-target-url="/admin/index_user.html" authentication-failure-url="/error_page.html" />
		<csrf disabled="true"/>	
		<headers>
			<frame-options policy="SAMEORIGIN"/>
		</headers>
		<loGout logout-url="/logout"/>
	</http>
	
	<!--配置登录的账号和密码-->
	<authentication-manager>
		<authentication-provider>
			<user-service>
				<user name="admin" passWord="123456" authorities="ROLE_ADMIN"/>
			</user-service>
		</authentication-provider>
	</authentication-manager>		
</beans:beans>

<form class="sui-form" action="/login" method="post" id="loginform">
							
								<div class="input-prepend"><span class="add-on loginname"></span>
									<input id="prependedInput" type="text" name="username" placeholder="用户名" class="span2 input-xfat">
								</div>
								
								<div class="input-prepend"><span class="add-on loginpwd"></span>
									<input id="prependedInput" type="password" name="password" placeholder="密码" class="span2 input-xfat">
								</div>
								
								<div class="logined">
									<a class="sui-btn btn-block btn-xlarge btn-danger" onclick="doucment:loginform.submit()" target="_blank">登&nbsp;&nbsp;录</a>
								</div>
							</form>

<form class="sui-form" action="/investigation/login" method="post" id="loginform"><!--此处action需要加上工程的路径-->
							
								<div class="input-prepend"><span class="add-on loginname"></span>
									<input id="prependedInput" type="text" name="username" placeholder="用户名" class="span2 input-xfat">
								</div>
								
								<div class="input-prepend"><span class="add-on loginpwd"></span>
									<input id="prependedInput" type="password" name="password" placeholder="密码" class="span2 input-xfat">
								</div>
								
								<div class="logined">
									<a class="sui-btn btn-block btn-xlarge btn-danger" onclick="doucment:loginform.submit()" target="_blank">登&nbsp;&nbsp;录</a>
								</div>
							</form>