java创建对象的4种方式

//待创建的类
/**
* 创建对象的方式1
* colone-------克隆
*/
public class Hello implements Cloneable {

public void sayHello(){
    System.out.println("hello world");
}

public static void main(String[] args) {
    Hello h1 = new Hello();
    try {
        Hello h2 = (Hello) h1.clone();
        h2.sayHello();
    } catch (CloneNotSupportedException e) {
        e.printStackTrace();
    }
}

}
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
public class Hello_2 implements Serializable {
/**
* 创建对象的方式2
* 序列化
*/
public static void main(String[] args) {

    Hello h = new Hello();
    //使用物理内存存储
    File f = new File("D:\\File-Copy\\one\\hello.obj");

    try {
        FileOutputStream fos = new FileOutputStream(f);
        ObjectOutputStream oos = new ObjectOutputStream(fos);
        FileInputStream fis = new FileInputStream(f);
        ObjectInputStream ois = new ObjectInputStream(fis);
        //序列化对象,写入磁盘中
        oos.writeObject(h);
        //反序列化对象
        Hello newHello = (Hello) ois.readObject();
        //测试方法
        newHello.sayHello();
    } catch (IOException e) {
        e.printStackTrace();
    } catch (ClassNotFoundException e) {
        e.printStackTrace();
    }
}

}
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
public class NewClass_1 {
public static void main(String[] args) {
/**
* 创建对象的方式3,
* new
/
Hello h = new Hello();
h.sayHello();
}
}
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
/*
* 创建对象方式4
* 反射
*/
public class NewClass_2 {

public static void main(String[] args) {
    try {
        Class heroClass  = Class.forName("cn.itcast.demo.Hello");
        Hello h = (Hello) heroClass .newInstance();
        h.sayHello();

    } catch (ClassNotFoundException e) {
        e.printStackTrace();
    } catch (InstantiationException e) {
        e.printStackTrace();
    } catch (IllegalAccessException e) {
        e.printStackTrace();
    }

}

}
总结,java创建对象的四种方式有序列化,new,反射,克隆.

java创建对象的4种方式

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