String转JSONArray,遍历JSONArray，Array数组转换成JSON字符串

<!-- https://mvnrepository.com/artifact/org.json/json -->
<dependency>
    <groupId>org.json</groupId>
    <artifactId>json</artifactId>
    <version>20201115</version>
</dependency>

	/**
	 * String转JSONArray
	 */
	public static void test1(){
		String json = "[{\"name\":\"张三\",\"code\":\"123\"},{\"name\":\"李四\",\"code\":\"123\"}]";
		JSONArray jsonArray = new JSONArray(json); 
		System.out.println("String转JSONArray: "+jsonArray);
		System.out.println();
	}

	/**
	 * 遍历JSONArray
	 * JSONArray含义：array数组,只不过数组是json格式的
	 */
	public static void test2(){
		String json = "[{\"name\":\"张三\",\"code\":\"123\"},{\"name\":\"李四\",\"code\":\"123\"}]";
		JSONArray jsonArray = new JSONArray(json); 
		if(jsonArray.length() > 0){
			for (int i = 0; i < jsonArray.length(); i++) {
				JSONObject jsonObject = jsonArray.getJSONObject(i);
				System.out.println("遍历jsonArray,获取数组中的name属性值："+jsonObject.get("name"));
			}
		}
		System.out.println();
	}

	/**
	 * Array数组转换成JSON字符串
	 * json字符串含义：字符串是json格式的
	 */
	public static void test3(){
		ArrayList<User> users = new ArrayList<User>();
		users.add(new User("zhangsan",21));
		users.add(new User("lisi",18));
		users.add(new User("wangwu",32));
		
		JSONArray array = new JSONArray(users);		
		System.out.println("Array数组转JSON字符串： "+array.toString());
	}