Fastjson JSONObject深度复制

Fastjson JSONObject深度复制

目录

Fastjson JSONObject深度复制

1，new JSONObject (Object) - 失败

2，Put All;

3，串行化复制;

总结：

---

如何对fajstjson JSONObject类型的数据进行深度复制，有几种方式呢？

 

1，new JSONObject (Object) - 失败

 

代码：

public static void main(String[] args) throws IOException, ClassNotFoundException {
    testNewJson();
}

public static void testNewJson(){
    System.out.println("====== new JSONObject fail =======");
    JSONObject one = new JSONObject();
    one.put("one","fish");
    JSONObject two = new JSONObject(one);
    System.out.println("init: one: "+ one.toString());
    System.out.println("init: two: "+ two.toString());
    System.out.println("====== add grass =======");
    two.put("two","grass");
    System.out.println("change: one: "+ one.toString());
    System.out.println("change: two: "+ two.toString());
    System.out.println("====== new JSONObject fail =======");
}

 

结果：

====== new JSONObject fail =======

init: one: {"one":"fish"}

init: two: {"one":"fish"}

====== add grass =======

change: one: {"one":"fish","two":"grass"}

change: two: {"one":"fish","two":"grass"}

====== new JSONObject fail =======

new JSONObject(one) 这种方式失败了 new JSONObject(Object)深复制失败的原因​​​​​​​

2，Put All;

代码：

public static void main(String[] args) throws IOException, ClassNotFoundException {
    testPutAllJson();
}

public static void testPutAllJson(){
    System.out.println("====== put all =======");
    JSONObject one = new JSONObject();
    one.put("one","fish");
    JSONObject two = new JSONObject();
    two.putAll(one);
    System.out.println("init: one: "+ one.toString());
    System.out.println("init: two: "+ two.toString());
    System.out.println("====== add fox =======");
    two.put("two","fox");
    System.out.println("change: one: "+ one.toString());
    System.out.println("change: two: "+ two.toString());
    System.out.println();
}

结果：

====== put all =======

init: one: {"one":"fish"}

init: two: {"one":"fish"}

====== add fox =======

change: one: {"one":"fish"}

change: two: {"one":"fish","two":"fox"}

 putAll的方式行得通

 

3，串行化复制;

 

代码：

public static void main(String[] args) throws IOException, ClassNotFoundException {
    testDeppCopyJson();
}

public static void testDeppCopyJson() throws IOException, ClassNotFoundException {
    System.out.println("====== serializable success =======");
    JSONObject one = new JSONObject();
    one.put("one","fish");
    JSONObject two =  CloneUtils.clone(one);
    two.putAll(one);
    System.out.println("init: one: "+ one.toString());
    System.out.println("init: two: "+ two.toString());
    System.out.println("====== add wolf =======");
    two.put("two","wolf");
    System.out.println("change: one: "+ one.toString());
    System.out.println("change: two: "+ two.toString());
    System.out.println();
}

 

串行化代码：

public class CloneUtils {

    public static  T clone(T src) throws IOException, ClassNotFoundException {
        ObjectInputStream ois = getInputStream(src);
        //返回生成的新对象
        @SuppressWarnings("unchecked")
        T cloneObj = (T) ois.readObject();
        ois.close();
        return cloneObj;

    }

    public static  List deepCopy(List src) throws IOException, ClassNotFoundException {
        ObjectInputStream ois = getInputStream(src);
        @SuppressWarnings("unchecked")
        List dest = (List) ois.readObject();
        ois.close();
        return dest;
    }
 
    public static  Map cloneMap(Map src) throws IOException, ClassNotFoundException {
        ObjectInputStream ois = getInputStream(src);
        @SuppressWarnings("unchecked")
        Map result =   (Map)     ois.readObject();
        ois.close();
        return result;

    }

    private static ObjectInputStream getInputStream(Object src) throws IOException, ClassNotFoundException {
        //写入字节流
        ByteArrayOutputStream out = new ByteArrayOutputStream();
        ObjectOutputStream obs = new ObjectOutputStream(out);
        obs.writeObject(src);
        obs.close();
        //分配内存，写入原始对象，生成新对象
        ByteArrayInputStream ios = new ByteArrayInputStream(out.toByteArray());
        return new ObjectInputStream(ios);
    }
}

 

结果：

====== serializable success =======

init: one: {"one":"fish"}

init: two: {"one":"fish"}

====== add wolf =======

change: one: {"one":"fish"}

change: two: {"one":"fish","two":"wolf"}

 

总结：

   在使用fastjon JSONObject复制的时候，一般用第二种putAll的方式，如果大量使用，也可以考虑用第三种方式。