先来看下前端项目jsp代码：
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@include file="../../../../common/commonBase.jsp"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<base href="<%=basePath%>">
<title>My JSP 'Test.jsp' starting page</title>
</head>
<input type="button" onclick="testAjax()" value="获取数据">
<body>
<script type="text/javascript">
function testAjax() {
var users = [ {
name : '张三',
age : '21',
birth : '1994-12-12'
}, {
name : '李四',
age : '20',
birth : '1995-12-11'
}, {
name : 'wangwu',
age : '20',
birth : '1995-12-11'
} ];
$.ajax({
type : 'POST',
data : JSON.stringify(users),
contentType : 'application/json',
dataType : 'json',
url : "http://localhost:8080/TestSolr/search/BaseTollgate/test",
success : function(data) {
alert("OK");
},
error : function(e) {
alert("error");
}
});
}
</script>
</body>
</html>
后端项目controller信息接受代码
@RequestMapping("/test")
@ResponseBody
public void test(@RequestBody User[] users){
for (User user : users) {
System.out.println(user.toString());
}
}
如果此时没有设置后端的filter的话，就会报这个错误
Response to preflight request doesn't pass access control check: No 'Access-Control-Allow-Origin'
意思差不多就是被限制了不能够被访问到，原因我理解的就是filter禁止和本项目域名不同的地址所访问，那么知道了这个就好办了，集体解决方法如下
先在后端项目中添加一个filter类，进行代码编写，其实代码都差不多，可以直接复制上去
package com.xqsm.filter;
import java.io.IOException;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.commons.httpclient.HttpStatus;
public class CorsFilter implements Filter {
public void init(FilterConfig filterConfig) throws ServletException {
}
public void doFilter(ServletRequest servletRequest,
ServletResponse servletResponse, FilterChain filterChain)
throws IOException, ServletException {
HttpServletResponse response = (HttpServletResponse) servletResponse;
HttpServletRequest request = (HttpServletRequest) servletRequest;
// 指定允许其他域名访问
response.setHeader("Access-Control-Allow-Origin", "*");
// 响应类型
response.setHeader("Access-Control-Allow-Methods",
"POST, GET, DELETE, OPTIONS, DELETE");
// 响应头设置
response.setHeader("Access-Control-Allow-Headers",
"Content-Type, x-requested-with, X-Custom-Header, HaiYi-Access-Token");
if ("OPTIONS".equals(request.getMethod())) {
response.setStatus(HttpStatus.SC_NO_CONTENT);
}
filterChain.doFilter(servletRequest, servletResponse);
}
public void destroy() {
}
}
其中这段代码
// 指定允许其他域名访问
response.setHeader("Access-Control-Allow-Origin", "*");
就是设置域名的访问权限了，里面的*代表着所有域名了，如果想规定哪些域名的话，就直接在里面改就行了，最后需要把我们编写好的filter放到web容器中去，也就是web.xml，在里面添加下面这段代码
<filter>
<filter-name>cors</filter-name>
<filter-class>com.xqsm.filter.CorsFilter(这里是你编写的filter地址)</filter-class>
</filter>
<filter-mapping>
<filter-name>cors</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
最后进行前端项目访问，在到后端去看输出的信息，发现后端成功收到信息，这样就解决了项目之间的跨域问题了。。