jQuery与Servlet配合实现跨域请求

jQuery与Servlet配合实现跨域请求:

方法：1.ajax post到servlet

2.servlet远程访问远程url，并返回数据给页面。

public void doPost(HttpServletRequest req, HttpServletResponse resp) 

throws ServletException, IOException { 
        boolean requestType = false;//标记远程请求类型，默认为GET方式 
        PrintWriter out = resp.getWriter(); 
        Enumeration keys = req.getParameterNames();//取出客户端传入的所有参数名 
        ArrayList<String> params = new ArrayList<String>(); 
        String url=null; 
        while (keys.hasMoreElements()){ 
            String key = (String) keys.nextElement(); 
            
            params.add(key);//其它加入参数列表，此处为参与远程请求的参数 
            requestType = true;//修改标记，表求远程请求为POST方式 
           
        } 
         
        HttpClient client = new HttpClient(); 
        HttpMethod method = null; 
        if(requestType){//判断请求方式，并实例化HttpMethod对象，true:POST,false:GET 
            method = new UTF8PostMethod(url); 
            for(String name : params){//迭代POST参数，加入到请求中 
                String _value = req.getParameter(name); 
                ((PostMethod)method).setParameter(name,_value); 
            } 
        }else{ 
            method = new GetMethod(url); 
        }        
        client.executeMethod(method);//执行请求 
        String bodystr = method.getResponseBodyAsString();//返回结果 
        out.println(bodystr);//将结果返回给客户端 
    } 
     
    /**
     * 内部类，转换URL字符串为UTF-8
     * @author Administrator
     *
     */ 
    private static class UTF8PostMethod extends PostMethod {  
        public UTF8PostMethod(String url) {  
            super(url);  
        }  
        @Override  
        public String getRequestCharSet() {  
            return "UTF-8";  
        }  
    }