STRUTS2 return JSON data (using STRUTS2 plugin)

This article will show you how to use Struts2 's Struts2-json-plugin.jar plugin to return JSON data.

First, the main steps are:

1. Copy the Struts2-json-plugin.jar plugin to the project's "/web-inf/lib" folder;

2. Write the action class file;

3. Configure this action in the Struts.xml file, the action "<package.../>" must inherit "Json-default", the action of the result type is JSON, that is, type= "JSON" and does not correspond to any view resources.

Second, the sample code:

Action class file:

 Packagecom.example.action;Importjava.util.ArrayList;ImportCom.opensymphony.xwork2.ActionSupport; Public classStrutsjsonactionextendsActionsupport {Private intI=123; PrivateString str= "str"; Private int[] array={1,2,3}; PrivateArraylist<string>list;  Public intGeti () {returni; }     Public voidSetI (inti) { This. i =i; }     PublicString getstr () {returnstr; }     Public voidsetstr (String str) { This. str =str; }     Public int[] GetArray () {returnArray; }     Public voidSetArray (int[] Array) {         This. Array =Array; }     PublicArraylist<string>getList () {returnlist; }     Public voidSetlist (arraylist<string>list) {         This. List =list; }     PublicString Execute () {list=NewArraylist<string>(); List.add ("Red"); List.add ("Green"); List.add ("Yellow"); returnSUCCESS; }}

Struts.xml file:

<?XML version= "1.0" encoding= "UTF-8"?><!DOCTYPE struts Public "-//apache software foundation//dtd struts Configuration 2.1//en" "http://struts.apache.org/ Dtds/struts-2.1.dtd "><Struts>    < Packagename= "Json-example"namespace="/"extends= "Json-default">        <Actionname= "Jsonexample"class= "Com.example.action.StrutsJsonAction">            <resultname= "Success"type= "JSON"/>        </Action>    </ Package></Struts>    

Then access "http://localhost:8080/Struts2_JSON/JSONExample" in the browser to display the results

The JSON plug-in serializes all serializable action properties into JSON data.

Third, configure the JSON type of result:

Serialization contains the attributes:

<resulttype= "JSON"> 　　 <!--whether to cancel the browser cache - 　　 <paramname= "NoCache">True</param> 　　 <!--Setting the server response type - 　　 <paramname= "ContentType">Application/json</param> 　　 <!--matching expression property names are serialized - 　　 <paramname= "Includeproperties">I,str</param> </result>

Serializes only the specified action property:

<resulttype= "JSON"> 　　  <!--whether to cancel the browser cache -  　　 <paramname= "NoCache">True</param> 　　  <!--Setting the server response type -  　　 <paramname= "ContentType">Application/json</param>  　　 <!--serializes only the properties specified within the action - 　　 <paramname= "root">List</param></result>

STRUTS2 return JSON data (using STRUTS2 plugin)