20.深拷贝和浅拷贝的区别是什么?

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5然 U"ĩ hashCode?

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ď知https://blog.csdn.net/xlgen157387/article/details/88087963

20.Čʇƴ4Ȭʇƴ Ť I!?

ͫ现ɨ

ʊ1ʋʈ ƽ

yǫĴ<ȴ Æõ ˳ªì <ȴ· ǭҊj <ÅJ<ȴ ʙF͢]Ɨđì <

package com.test;

public class ShallowCopy { public static void main(String[] args) throws CloneNotSupportedException

{ Teacher teacher = new Teacher();

teacher.setName("riemann");

teacher.setAge(27);

Student2 student1 = new Student2();

student1.setName("edgar");

student1.setAge(18);

student1.setTeacher(teacher);

Student2 student2 = (Student2) student1.clone();

System.out.println("拷贝贝后");

System.out.println(student2.getName());

System.out.println(student2.getAge());

System.out.println(student2.getTeacher().getName());

System.out.println(student2.getTeacher().getAge());

System.out.println("修改老老老师的信息后——————");

// 修改老老老师的信息 teacher.setName("Games");

System.out.println(student1.getTeacher().getName());

System.out.println(student2.getTeacher().getName());

} }

class Teacher implements Cloneable { private String name;

private int age;

public String getName() { return name;

}

public void setName(String name) { this.name = name;

}

public int getAge() { return age;

}

public void setAge(int age) {

private String name;

private int age;

private Teacher teacher;

public String getName() { return name;

}

public void setName(String name) { this.name = name;

}

public int getAge() { return age;

}

public void setAge(int age) { this.age = age;

}

public Teacher getTeacher() { return teacher;

}

public void setTeacher(Teacher teacher) { this.teacher = teacher;

}

public Object clone() throws CloneNotSupportedException { Object object = super.clone();

return object;

} }

̫7Āp:

拷贝贝后 edgar

18 riemann

27 修改老老老师的信息后——————

Games Games

ŕ现ɨ

ʊ1ʋʈ ƽ

ŕ现ɨ džLjǸ <ȴ现ɨҊŕ现ɨ 现ɨ Ŏ¸,Č现ɨŎ¸Ɨđ aDž2Ȓ ĂȘѽ©< ȴ;ı ʙF <ȴ 1现ɨ$ľ:*ŕ现ɨѽŕ现ɨ·º ͫ现ɨDŽîȾǮČɽÑˍȾ ѽ

ǰjǯiҊŕ现ɨ ǫĴ <ȴ ʙF <ȴ ǫĴ ʖѽ

ʊ2ʋʈČʇƴ Ƀ

package com.test;

public class DeepCopy { public static void main(String[] args) throws CloneNotSupportedException

{ Teacher2 teacher = new Teacher2();

teacher.setName("riemann");

teacher.setAge(27);

Student3 student1 = new Student3();

student1.setName("edgar");

student1.setAge(18);

student1.setTeacher(teacher);

Student3 student2 = (Student3) student1.clone();

System.out.println("拷贝贝后");

System.out.println(student2.getName());

System.out.println(student2.getAge());

System.out.println(student2.getTeacher().getName());

System.out.println(student1.getTeacher().getName());

System.out.println(student2.getTeacher().getName());

} }

class Teacher2 implements Cloneable { private String name;

private int age;

public String getName() { return name;

}

public void setName(String name) { this.name = name;

}

public int getAge() { return age;

}

public void setAge(int age) { this.age = age;

}

public Object clone() throws CloneNotSupportedException { return super.clone();

} }

class Student3 implements Cloneable { private String name;

private int age;

private Teacher2 teacher;

public String getName() { return name;

}

public void setName(String name) { this.name = name;

}

public int getAge() { return age;

}

return teacher;

}

public void setTeacher(Teacher2 teacher) { this.teacher = teacher;

}

public Object clone() throws CloneNotSupportedException { // 浅复制时：

// Object object = super.clone();

// return object;

// 改为深复制：

Student3 student = (Student3) super.clone();

// 本来是浅复制，现在将Teacher对象复制一一份并重新set进来 student.setTeacher((Teacher2) student.getTeacher().clone());

return student;

} }

̫7Āp知

拷贝贝后 edgar

18 riemann

27 修改老老老师的信息后——————

Games riemann

Āp2ί知 lʙFstudent1;student2Ɨđ l<ȴҊlʙFstudent1;student2 lteacherʙF

Ɨđ l<ȴҊ´<teacher<ȴ ȰƇE İʡstudent1<ȴ, 5' ŕ现ɨѽ