Java Enum clone() 方法

2024年11月8日 | 2 分钟阅读

Enum 类的 clone() 方法会抛出 CloneNotSupportedException。该方法确保枚举不能被克隆，这有助于维护其“单例”属性。

语法

Override

Enum 类的 clone() 方法重写了 Object 类的 clone() 方法。

返回值

clone() 方法不返回任何内容。

抛出

如果对象的类不支持 Cloneable 接口，则 clone() 方法会抛出 CloneNotSupportedException。重写此方法的子类也可以抛出 CloneNotSupportedException 异常，以表明实例不能被克隆。

示例 1

import java.lang.*;

enum Colour{
Red,Pink,Black,Blue,White,red;
}
public class Enum_cloneMethodExample1 {
    String Red;

public static void main(String[] args) {
        Enum_cloneMethodExample1 enu = new Enum_cloneMethodExample1() {
protected final Object clone() throws CloneNotSupportedException {
throw new CloneNotSupportedException();
            }
        };
        Colour col = Colour.Red;

switch (col) {
case Red:
System.out.println("People with Red as their favourite colour are generally wiser.");
break;
case Blue:
System.out.println("People with Blue as their favourite colour are ambitious in life.");
break;
case Black:
System.out.println("People with Black as their favourite colour are soft hearted and are head strong.");
break;
case White:
System.out.println("Peoples with White as their favourite colour are benevolent and loving .");
break;
case Pink:
System.out.println("Peoples with Pink as their favourite colour are beautiful and intelligent.");
break;
        }
        }
        }

输出

People with Red as their favourite colour are generally wiser.

示例 2

import java.lang.*;

enum Vehicle{

MarutiI(2010), MarutiII(2013),MarutiIII(2016);

int model;

Vehicle(int m) {
model  = m;

    }

int showModel() {
return model;

    }
}

public class Enum_cloneMethodExample2 {

public static void main(String[] args) {

System.out.println("Maruti Car models till yet:");

//Enums can never be cloned...

Object t = new Enum_cloneMethodExample2() {

protected final Object clone() throws CloneNotSupportedException {

throw new CloneNotSupportedException();
            }

        };

for(Vehicle m : Vehicle.values()) {

System.out.println(m + " launched in " + m.showModel() + " year.");

        }
    }
}

输出

Maruti Car models till yet:
MarutiI launched in 2010 year.
MarutiII launched in 2013 year.
MarutiIII launched in 2016 year.

下一主题Java-enum-compareto-method

Java Enum clone() 方法

语法

Override

返回值

抛出

示例 1

示例 2

联系信息

关注我们

教程

面试题

在线编译器

Python

Java

.Net Framework

AI, ML and Data Science

Cloud Technology

B.Tech and MCA

Web Technology

PHP

Software Testing

Technical Interview

Java Interview

Python

Web Interview

Database Interview

B.Tech / MCA

Important Interview

Software Testing Interview

Company Interviews

Online Compilers

Multiple Choice Questions

Java EnumMap

Java DriverManager

Java ThreadLocal

Java StringBuilder

Java StringBuffer

Java Short

Java Float

Java HashSet

Java ThreadLocalRandom

Java ThreadGroup

Java Double

Java Throwable

Java PriorityQueue

Java Matcher

Java 方法

Java 枚举

Java TreeSet

Java TimeZone

Java System

Java Locale

Java Scanner

Java Random

Java Currency

Java Character

Java Timertask

Java Timer

Java Process

Java Calendar

Java Enum clone() 方法

语法

Override

返回值

抛出

示例 1

示例 2

相关帖子

Java Enum ordinal() 方法

Java Enum getDeclaringClass() 方法

Java Enum compareTo() 方法

Java Enum equals() 方法

Java Enum finalize() 方法

Java Enum name() 方法

Java Enum valueOf() 方法

Java Enum toString() 方法

Java Enum hashCode() 方法

订阅 Tpoint Tech

联系信息

关注我们

教程

面试题

在线编译器