Java将list数组中重复的对象进行去重

news2024/12/23 10:45:16

/**
 * 数组去重
 */
public class ArrayDistinct {
    public static void main(String[] args) {
        ArrayList<Object> list = new ArrayList<>();

        JSONObject jsonObject1 = new JSONObject();
        jsonObject1.put("name","张三");
        jsonObject1.put("age",20);
        jsonObject1.put("gender","男");
        jsonObject1.put("money",200);

        JSONObject jsonObject2 = new JSONObject();
        jsonObject2.put("name","李四");
        jsonObject2.put("age",20);
        jsonObject2.put("gender","女");
        jsonObject2.put("money",100);

        list.add(jsonObject1);
        list.add(jsonObject1);
        list.add(jsonObject2);
        System.out.println(list);
    }
}

输出数组结果：

[
    {
        "gender": "男",
        "money": 200,
        "name": "张三",
        "age": 20
    },
    {
        "gender": "男",
        "money": 200,
        "name": "张三",
        "age": 20
    },
    {
        "gender": "女",
        "money": 100,
        "name": "李四",
        "age": 20
    }
]

预期结果：

[{"gender":"男","money":200,"name":"张三","age":20}, {"gender":"女","money":100,"name":"李四","age":20}]

实现方法：在输出前加上以下代码即可实现：

// 转为stream，利用distinct方法去重
list = list.stream().distinct().collect(Collectors.toList());

完整代码：

public class ArrayDistinct {
    public static void main(String[] args) {
        List<Object> list = new ArrayList<>();

        JSONObject jsonObject1 = new JSONObject();
        jsonObject1.put("name","张三");
        jsonObject1.put("age",20);
        jsonObject1.put("gender","男");
        jsonObject1.put("money",200);

        JSONObject jsonObject2 = new JSONObject();
        jsonObject2.put("name","李四");
        jsonObject2.put("age",20);
        jsonObject2.put("gender","女");
        jsonObject2.put("money",100);

        list.add(jsonObject1);
        list.add(jsonObject1);
        list.add(jsonObject2);

        System.out.println("去重前："+list);
        // 转为stream，利用distinct方法去重
        list = list.stream().distinct().collect(Collectors.toList());
        System.out.println("去重后："+list);
    }
}

输出：