<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">

<modelVersion>4.0.0</modelVersion>

<groupId>com.hmkcode</groupId>

<artifactId>gson-json-java</artifactId>

<version>1.0-SNAPSHOT</version>

<packaging>jar</packaging>

<name>gson-json-java</name>

<url>http://maven.apache.org</url>

<properties>

<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>

</properties>

<dependencies>

<dependency>

<groupId>com.google.code.gson</groupId>

<artifactId>gson</artifactId>

<version>2.2.4</version>

</dependency>

</dependencies>

</project>

package com.hmkcode;

import java.lang.reflect.Type;

import java.util.LinkedList;

import java.util.List;

import com.google.gson.Gson;

import com.google.gson.reflect.TypeToken;

import com.hmkcode.vo.Article;

public class App

{

public static void main( String[] args )

{

Gson gson = new Gson();

List<Article> articles = new LinkedList<Article>();

articles.add(createArticle());

articles.add(createArticle());

// Java --> JSON

String json = gson.toJson(articles);

System.out.println("toJson: "+json);

// JSON --> Java

List list = gson.fromJson(json, List.class);

System.out.println("fromJson: "+list);

System.out.println("Class Type: "+list.get(0).getClass());

// JSON --> Java "Get the actual type"

Type type = new TypeToken<List<Article>>(){}.getType();

list = gson.fromJson(json, type);

System.out.println("fromJson: "+list);

System.out.println("Class Type: "+list.get(0).getClass());

}

private static Article createArticle(){

Article article = new Article();

article.setTitle("GSON - Java JSON Library");

article.setUrl("http://hmkcode.com/gson-json-java");

article.addCategory("Java");

article.addTag("Java");

article.addTag("GSON");

article.addTag("JSON");

return article;

}

}

package com.hmkcode.vo;

import java.util.LinkedList;

import java.util.List;

public class Article {

private String title;

private String url;

private List<String> categories;

private List<String> tags;

public String getTitle() {

return title;

}

public void setTitle(String title) {

this.title = title;

}

public String getUrl() {

return url;

}

public void setUrl(String url) {

this.url = url;

}

public List<String> getCategories() {

return categories;

}

public void setCategories(List<String> categories) {

this.categories = categories;

}

public List<String> getTags() {

return tags;

}

public void setTags(List<String> tags) {

this.tags = tags;

}

public void addCategory(String category){

if(this.categories == null)

this.categories = new LinkedList<String>();

this.categories.add(category);

}

public void addTag(String tag){

if(this.tags == null)

this.tags = new LinkedList<String>();

this.tags.add(tag);

}

@Override

public String toString() {

return "Article [title=" + title + ", url=" + url + ", categories="

+ categories + ", tags=" + tags + "]";

}

}