1. 程式人生 > >java只有值傳遞(P123)

java只有值傳遞(P123)

new的物件儲存的是棧中的地址,並不是物件本身。
因此在當引數進行傳遞的時候,單純的對物件例項進行操作,並不會影響方法之外。

public class Person {
	public Person() {}
	public Person(String name) 
	{
		this.name = name;
	}
	private String name;
	
	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
	
	public static void xiugai(Person p)
	{
		p.setName("wangwu");
	}
	
	public static void jiaohuan(Person p1 ,Person p2)
	{
		Person temp = p1;
		p1 = p2;
		p2 = temp;
		xiugai(p1);
	}
	public static void main(String[] args) {
		Person p1 = new Person("zhagnsan");
		Person p2 = new Person("lisi");
		Person.jiaohuan(p1, p2);
		System.out.println(p1.getName() + "    " + p2.getName());
	}
}
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" 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