面试题4：替换空格

package 剑指Offer;


import java.util.Stack;


public class Main4 {


public static void main(String[] args) {
// TODO Auto-generated method stub
String str = "We are heppy.";
System.out.println(replaceBlank(str));
}

public static String replaceBlank(String str) {
StringBuffer sb = new StringBuffer();

for(int i = 0; i < str.length(); i++) {
if(str.charAt(i) != ' ') {
sb.append(str.charAt(i));
} else {
sb.append('%');
sb.append('2');
sb.append('0');
}
}

//String temp = sb.toString();
return sb.toString();
}
}