基本数据类型与引用数据类型传递

public class PassValue{
public static void main(String[] args){
PassValue pv = new PassValue();
int x = 5;
System.out.println("方法调用之前x==" + x);//5
pv.change(x);//100
System.out.println("方法调用之后x==" + x);//5
}

public void change(int y){//y = 5;
y = 100;
System.out.println("方法中y==" + y);//100
}
}

public class PassValue2{
private int x ;
public static void main(String[] args){
PassValue2 obj = new PassValue2();
obj.x = 5;
System.out.println("方法调用之前obj.x==" + obj.x);//5
obj.change(obj);//100
System.out.println("方法调用之后obj.x==" + obj.x);//100
}

public void change(PassValue2 obj2){
obj2.x = 100;
System.out.println("方法中obj2.x==" + obj2.x);//100
}
}