passbyvalue1.java

这是一些java小程序的源码

//c3:PassByValue1.java
//author:ZhangHongbin 
//This program is protected by copyright laws.
//Pass By Value.  
public class PassByValue1
{
	int i=0;
	PassByValue1(int newValue)
	{
		i=newValue;
	}
	static void changeInt(int value)
	{
		value=98;
		System.out.println("value in changeInt()= "+value);

	}
	static void changeObjRef(PassByValue1 obj)
	{
			obj=new PassByValue1(99);	
			System.out.println("obj.i in changeObjRef()= "+obj.i);

	}
	static void changeObjAttr(PassByValue1 obj)
	{
			obj.i=100;	
			System.out.println("obj.i in changeObjAttr()= "+obj.i);

	}

	public static void main(String[] args) 
	{
		int value=2;
		System.out.println("value before changeInt()= "+value);
		changeInt(value);
		System.out.println("value after changeInt()= "+value);
		PassByValue1 obj =new PassByValue1(2);
		System.out.println("--------------------------------");
		System.out.println("obj before changeObjRef()= "+obj);
		System.out.println("obj.i before changeObjRef()= "+obj.i);
		changeObjRef(obj);
		System.out.println("obj.i after changeObjRef()= "+obj.i);
		System.out.println("obj after changeObjRef()= "+obj);
		System.out.println("--------------------------------");
		System.out.println("obj before changeObjAttr()= "+obj);

		System.out.println("obj.i before changeObjAttr()= "+obj.i);
		changeObjAttr(obj);
		System.out.println("obj.i after changeObjAttr()= "+obj.i);
		System.out.println("obj after changeObjAttr()= "+obj);

	} 
}