基础问题
/n
/t
+""
代码里以上符号是什么意思、都是换行吗
问题点数:20、回复次数:5Top
1 楼masse(当午 http://blog.sina.com.cn/xukf)回复于 2005-08-02 17:32:38 得分 0
/n回车符号,相当于换行
/t制表符,就是键盘上的tab键
+"" 把一个非字符串的对象转化为字符串,比如
int i=5;
i+"" 就成了"5"字符串Top
2 楼rower203(华仔)回复于 2005-08-02 17:32:38 得分 0
\n 换行
\t 一个Table符
"" 什么字符都没有.Top
3 楼interhanchi(on the Java Road)回复于 2005-08-02 17:36:06 得分 0
import java.util.*;
class Shape{
void draw(){}
void erase(){}
void f(){
System.out.println("Shap");
}
}
class Circle extends Shape{
void draw(){
System.out.println("Circle.draw()");
}
void erase(){
System.out.println("Circle.erase()");
}
void f(){
System.out.println("Circle");
}
}
class Square extends Shape{
void erase(){
System.out.println("Square.erase()");
}
void draw(){
System.out.println("Square.draw()");
}
void f(){
System.out.println("Square");
}
}
class Triangle extends Shape{
void erase(){
System.out.println("Triangle.erase()");
}
void draw(){
System.out.println("Triangle.draw()");
}
void f(){
System.out.println("Triangle");
}
}
class Ellipse extends Shape{
void erase(){
System.out.println("Ellipse.erase()");
}
void draw(){
System.out.println("Ellipse.draw()");
}
void f(){
System.out.println("Ellipse");
}
}
class RandomShapeGenerator{
private Random rand = new Random();
public Shape next(){
switch(rand.nextInt(4)){
default:
case 0: return new Circle();
case 1: return new Square();
case 2: return new Triangle();
case 3: return new Ellipse();
}
}
}
public class Shapes{
private static RandomShapeGenerator gen = new RandomShapeGenerator();
public static void main(String[] args){
Shape[] s = new Shape[9];
for(int i = 0;i<s.length;i++){
s[i] = gen.next();
}
for(int i = 0;i<s.length;i++){
s[i].f();
s[i].draw();
}
}
}
RandomShapeGenerator就是一个工厂,每次调用next()都会产生一个引用!Top
4 楼rower203(华仔)回复于 2005-08-02 17:36:35 得分 0
\n换行符号,
\r回车符号
注意是反斜线.Top
5 楼interhanchi(on the Java Road)回复于 2005-08-02 17:38:46 得分 0
sor帖错了!楼上的正解!Top




