jsonp跨域，后台json需要包装

java后台：

package cn.xuwx;

import java.io.IOException;
import java.io.PrintWriter;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * Servlet implementation class test
 */
public class test extends HttpServlet {
    private static final long serialVersionUID = 1L;

    public test() {
        super();
    }

    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        resp.setContentType("text/html;charset=UTF-8");
        resp.setCharacterEncoding("utf-8");

        String result = "{\"name\":\"许文祥\",\"address\":\"武汉\"}";
        String jj = "successCallback("+result+")";
        PrintWriter out = resp.getWriter();
        out.write(jj);
    }

    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

    }

}

前台：

$.ajax({
        url: ‘http://localhost:8081/Servlet/test‘,
        dataType: ‘jsonp‘,
        jsonpCallback:"successCallback",
        success: function(data){
            console.log(JSON.stringify(data));
        },
        error: function(){
            console.log(‘失败‘);
        }
    })