技術標籤：Java中級

好記性不如爛筆頭，複習一下深克隆

實際使用時由於序列化的方式實現深度克隆效能較差，還是推薦使用Cloneable介面的方式重寫clone方法，但是注意該方法需要注意克隆物件的物件（多層）

話不多說，下面講一下深度克隆，深克隆實現相對簡單一點，只需要被克隆的物件實現Serializable介面，克隆的過程相對比較通用

被克隆物件：

import java.io.Serializable;

public class SerialCar implements Serializable {

    private static final long serialVersionUID = -7308342867043888945L;
    private String carType;
    private String carName;

    public SerialCar() {
    }

    public SerialCar(String carType, String carName) {
        this.carType = carType;
        this.carName = carName;
    }

    public String getCarType() {
        return carType;
    }

    public void setCarType(String carType) {
        this.carType = carType;
    }

    public String getCarName() {
        return carName;
    }

    public void setCarName(String carName) {
        this.carName = carName;
    }

    @Override
    public String toString() {
        return "SerialCar{" +
                "carType='" + carType + '\'' +
                ", carName='" + carName + '\'' +
                '}';
    }
}
 

import java.io.Serializable;

public class SerialUser implements Serializable {
    private static final long serialVersionUID = -2167957013938386204L;
    private String username;
    private SerialCar serialCar;

    public SerialUser() {
    }

    public SerialUser(String username, SerialCar serialCar) {
        this.username = username;
        this.serialCar = serialCar;
    }

    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    public SerialCar getSerialCar() {
        return serialCar;
    }

    public void setSerialCar(SerialCar serialCar) {
        this.serialCar = serialCar;
    }

    @Override
    public String toString() {
        return "SerialUser{" +
                "username='" + username + '\'' +
                ", serialCar=" + serialCar +
                '}';
    }
}
 

測試程式碼：

import java.io.*;

public class TestDeepClone {
    public static void main(String[] args) throws IOException, ClassNotFoundException {
        SerialUser serialUser = new SerialUser("李四", new SerialCar("賓士", "250"));

        ByteArrayOutputStream bos = new ByteArrayOutputStream();
        ObjectOutputStream oos = new ObjectOutputStream(bos);
        oos.writeObject(serialUser);

        ByteArrayInputStream bis = new ByteArrayInputStream(bos.toByteArray());
        ObjectInputStream ois = new ObjectInputStream(bis);
        SerialUser cloneUser = (SerialUser)ois.readObject();

        SerialCar cloneCar = cloneUser.getSerialCar();
        cloneCar.setCarType("奧迪");
        cloneCar.setCarName("A8");

        System.out.println(serialUser);
        System.out.println(cloneUser);
    }
}
 

測試結果：