Java常见笔试面试题目深度剖析系列之：Java方法参数传递详解

class ParamTest {

    public void changeInt(int i) {
        i = 2;
    }

    public void changeString(String str) {
        str = "xyz";
    }

    public void changePoint(Point point) {
        point.x = 5;
        point.y = 6;
    }

    public void change(char c, char[] ch) {
        c = 'A';
        ch[0] = 'B';
    }

    public static void main(String[] args) {
        ParamTest test = new ParamTest();

        int i = 1;
        test.changeInt(i);
        System.out.println("changeInt=" + i);

        String s = "abc";
        test.changeString(s);
        System.out.println("changeString=" + s);

        Point point = new Point(1, 2);
        test.changePoint(point);
        System.out.println("changePoint-->x=" + point.x);
        System.out.println("changePoint-->y=" + point.y);

        char c = 'C';
        char ch[] = new char[] { 'O', 'P', 'Q' };
        test.change(c, ch);
        System.out.println("change-->c=" + c);
        System.out.println("change-->ch[0]=" + ch[0]);
        
    }

}

class Point {
    int x;
    int y;

    public Point(int x, int y) {
        this.x = x;
        this.y = y;
    }
}

结果：

changeInt=1
changeString=abc
changePoint-->x=5
changePoint-->y=6
change-->c=C
change-->ch[0]=B