我还需要做什么/创建以使我的servlet和AJAX工作?

时间:2015-07-06 14:50:34

标签: java ajax eclipse tomcat servlets

我创建了一个AJAX Web应用程序,它应该向我的servlet发送一些数据(POSITIONS),这将在我的服务器中创建包含该数据的文本文件。问题是我不知道它是否有效,我不知道web.xml如何工作以及如何为我的应用配置它。
< / p>

更新:

我收到了CORS问题,但我的webapp.html和我的.war文件都在我的本地主机上。



服务器:Apache Tomcat 7.0
Eclipse EE Mars

提前谢谢。

PS:我在下面发布的片段只是为了观察,但我不能使用脚本,因为我不拥有图书馆所在的业务,如果你想看到它在上面的链接上查看它这个PostScript。

我的AJAX

    $(document).ready(function() {

      var POSITIONS;

      //var data is a dynamic JSON file that should be created in the backend.
      var data = [{
        label: 'node1',
        id: 1,
        children: [{
          label: 'child1',
          id: 2
        }, {
          label: 'child2',
          id: 3
        }]
      }, {
        label: 'node2',
        id: 4,
        children: [{
          label: 'child3',
          id: 5
        }]
      }];
      $('#tree1').tree({
        data: data,
        autoOpen: true,
        dragAndDrop: true
      });


      console.log($('#tree1').tree('toJson')); //This will give you the loading jqtree structure.

      $('#tree1').bind(
        'tree.move',
        function(event) {
          event.preventDefault();
          // do the move first, and _then_ POST back.
          event.move_info.do_move();
          console.log($(this).tree('toJson')); //this will give you the latest tree.
          POSITIONS = $(this).tree('toJson');
          alert(POSITIONS);
          $.post('http://sistema.agrosys.com.br/sistema/labs/CSS_HTML/', {
            tree: $(this).tree('toJson')
          });
          alert("done"); //this will post the json of the latest tree structure.
        }
      );

      var data = new FormData();
      data.append("JqTree", POSITIONS);
      alert('Sending: ' + POSITIONS);
      $.ajax({
        url: '/JqTree/Hello',
        type: 'POST',
        data: data,
        cache: false,
        dataType: 'json',
        processData: false,
        contentType: false,
        success: function(response) {
          alert("file has been successfully sent\n\n" + POSITIONS);
        },
        error: function(jqXHR, textStatus, errorThrown) {
          alert('ERRORS: ' + textStatus);
        }
      });

    });

我的Servlet

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;

public class Hello extends HttpServlet {
private static final long serialVersionUID = 1L;
public Hello() {}

protected void doGet(HttpServletRequest request, HttpServletResponse     response) throws ServletException, IOException {

    response.setContentType("text/html");
    PrintWriter out=response.getWriter();

    out.print("<html><body>");
    out.print("<h3>Hello Servlet</h3>");
    out.print("</body></html>");
}

 protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
     String position = request.getParameter("JqTree");

     PrintWriter writer = new PrintWriter("Positions.txt", "UTF-8");
     writer.println(position);
     writer.close();
}

}

和我的web.xml

<?xml version="1.0" encoding="UTF-8"?>

<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"     xmlns="http://java.sun.com/xml/ns/javaee" xmlns:web="http://java.sun.com/xml/ns/javaee"  xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" id="WebApp_ID" version="2.5">

<display-name>JqTree</display-name>


<welcome-file-list>


<welcome-file>index.html</welcome-file>    
<welcome-file>index.htm</welcome-file>    
<welcome-file>index.jsp</welcome-file>
<welcome-file>default.html</welcome-file>
<welcome-file>default.htm</welcome-file>
<welcome-file>default.jsp</welcome-file>
</welcome-file-list>

<servlet>

<description></description>

<display-name>Hello</display-name>
<servlet-name>Hello</servlet-name>
<servlet-class>Hello</servlet-class>
</servlet>

<servlet-mapping>  
<servlet-name>Hello</servlet-name>
<url-pattern>/Hello</url-pattern>
</servlet-mapping>

</web-app>

1 个答案:

答案 0 :(得分:1)

根据屏幕截图,您通过file://网址打开了HTML页面。当然,您将点击CORS墙,因为ajax请求不会在file://网址上触发,而是在http://localhost网址上触发。

修复file://网址也是一个值得信赖的http://localhost网址,绝不会将file://网址用于网络资源。将source.html文件移动到项目的公共Web内容中,然后通过以下方式打开它:

  

http://localhost/JqTree/source.html