解决跨域的jsonp+Java实例

 function getData( ) {
        $.ajax({
            var d1=$("#d11").val();
            url : "test/demoPage1.do",
            type : "GET",
            async:false,
            beforeSend : function(request) {
            },
            data : {
                     dtp1:d1,
             },
            dataType:‘jsonp‘, 
            jsonp:‘callback‘,      
            crossDomain:true,/*默认是false，记住要改为true，不然无法成功获取数据数据并跳转至success*/
            jsonpCallback:"callback",
            success:function(data){
                alert("success");
            },
            error:function(XMLHttpRequest, textStatus, errorThrown) {
                alert(XMLHttpRequest.status);
                alert(XMLHttpRequest.readyState);
                alert(textStatus);
            }
       });

@Action(value = "demoPage1", results = @Result(type = "json", params = {"root", "result" }))
public String getPage1Data() {
    Map<String,String> map = new HashMap<String,String>();   
    map.put("result", "content");  
    JSONObject resultJSON = JSONObject.fromObject(map);
    HttpServletResponse response=ServletActionContext.getResponse();
    HttpServletRequest resquest=ServletActionContext.getRequest();
    response.setContentType("text/plain");  
    response.setHeader("Pragma", "No-cache");  
    response.setHeader("Cache-Control", "no-cache");  
    response.setHeader("Access-Control-Allow-Origin", "*");//添加跨域访问
    response.setDateHeader("Expires", 0);   
    //String callback= request.getParameter("callback");//如果你在请求后面添加了callback，可以用自己传入的参数，没有添加则默认为callback，这里我使用默认
try {       
    PrintWriter out = response.getWriter();       
    out.println("callback"+"("+resultJSON.toString(1,1)+")");//返回jsonp格式数据 ，要用callback包装下
    out.flush();  
    out.close();  
    System.out.print("1");
} catch (Exception e) {
// TODO Auto-generated catch block
    e.printStackTrace();
    e.getMessage();
}
return null;
}