java入门基础------String练习1

class 练习1    //模仿trim功能，去掉两端空格
{
public static void sop(String str)
{
System.out.println(str);
}

public static void main(String[] args)
{
String s1 = "  asdasd f efew  ";
sop(mytrim(s1));
}

public static String mytrim(String str)
{
int start=0, end=str.length()-1;
while(start<=end && str.charAt(start)==' ')
start++;
while(start<=end && str.charAt(end)==' ')
end--;

return str.substring(start, end+1);
}
}