谷歌Gson简单测试

深藏阁楼爱情的钟 2022-06-06 00:36 226阅读 0赞

**1.废话不多说，先看结果：**

str类型是否为String:true
    gson.toJson(str):[1,2,3,4,5,6,9,8,45,4]
    map.toString():{k1=Wed Oct 25 14:17:36 CST 2017, k2=User [uname=小明, pwd=123]}
    gson.toJson(map):{"k1":"Oct 25, 2017 2:17:36 PM","k2":{"uname":"小明","pwd":"123"}}
    list.toString():[{k1=我是String对象, k2=User [uname=小狗, pwd=abc]}, {k1=我是String对象, k2=User [uname=小狗, pwd=abc]}]
    gson.toJson(list):[{"k1":"我是String对象","k2":{"uname":"小狗","pwd":"abc"}},{"k1":"我是String对象","k2":{"uname":"小狗","pwd":"abc"}}]
    list.toString():[{k1=我是String对象, k2=User [uname=小狗, pwd=abc]}, {k1=我是String对象, k2=User [uname=小狗, pwd=abc]}]
    原数组中下标为5的数字为：6
    还原后的list：[{k1=我是String对象, k2={uname=小狗, pwd=abc}}, {k1=我是String对象, k2={uname=小狗, pwd=abc}}]

**2.测试代码**

package 谷歌Gson;
    
    import java.util.Date;
    import java.util.HashMap;
    import java.util.LinkedList;
    import java.util.List;
    import java.util.Map;
    import java.util.Random;
    
    import com.google.gson.Gson;
    
    public class Test01 {
    
    	public static void main(String[] args) {
    		//创建Gson实例
    		Gson gson = new Gson();
    		int[] numbers = {1,2,3,4,5,6,9,8,45,4};
    		String str = gson.toJson(numbers);
    		System.out.println("str类型是否为String:"+( str instanceof String));
    		System.out.println("gson.toJson(str):"+str);
    		/*通过gson将Map类型数据转换为json格式*/
    		Map<String,Object> map = new HashMap<String,Object>();
    		map.put("k1", new Date());
    		map.put("k2", new User("小明","123"));
    		String s2 = gson.toJson(map);
    		System.out.println("map.toString():"+map.toString());
    		System.out.println("gson.toJson(map):"+s2);
    		/*通过gson将List类型转换为json格式*/
    		List<Map<String,Object>> list = new LinkedList<Map<String,Object>>();
    		map.clear();
    		map.put("l1", new Random().nextInt(255));
    		map.put("l2", new User("小花","789"));
    		list.add(map);
    		map.clear();
    		map.put("k1", "我是String对象");
    		map.put("k2", new User("小狗","abc"));
    		list.add(map);
    		String s3 = gson.toJson(list);
    		System.out.println("list.toString():"+list.toString());
    		System.out.println("gson.toJson(list):"+s3);
    		/*反转：将转换后的json格式还原*/
    		System.out.println("list.toString():"+list.toString());
    		System.out.println("原数组中下标为5的数字为："+gson.fromJson(str,int[].class)[5]);
    		System.out.println("还原后的list："+gson.fromJson(s3, new LinkedList<HashMap<String,User>>().getClass()));
    	}
    
    }