Review the code

[sharon daze]

Anyone please explain me why this code always goes into catch even exception is not thrown.

   
public class Propagate{

public static void main(String args[])
        {
        String str = "chetan" ;
        str = reverse(str);
        System.out.println("The reversed string is : " + str);
        }                 

public static String reverse(String str)
        {
        String stringToReturn="";
        System.out.println(str.length());
        try{

        for(int i = str.length(); i >=0; i--)
                {
                stringToReturn += str.charAt(i);
                System.out.println(str.charAt(i));                
                }

        }catch(Exception e)
                {
                System.out.println("String length is zero.");
                }
                return(stringToReturn);

        }
}

 

[HENRY: Add Code Tags]

[Henry Wong]

Anyone please explain me why this code always goes into catch even exception is not thrown

Well, if you had printed the exception in the catch block, you can see the reason for yourself.

But just by "eyeballing" (without running it), my guess would be because of an out of bounds exception.

Henry

[sharon daze]

Yes you are right

[Jesper de Jong]

Please use code tags when you post source code.

[Henry Zhi Lin]

sharon daze wrote:Anyone please explain me why this code always goes into catch even exception is not thrown.

   
public class Propagate{

public static void main(String args[])
        {
        String str = "chetan" ;
        str = reverse(str);
        System.out.println("The reversed string is : " + str);
        }                 

public static String reverse(String str)
        {
        String stringToReturn="";
        System.out.println(str.length());
        try{

        for(int i = str.length(); i >=0; i--)
                {
                stringToReturn += str.charAt(i);
                System.out.println(str.charAt(i));                
                }

        }catch(Exception e)
                {
                System.out.println("String length is zero.");
                }
                return(stringToReturn);

        }
}

 

 for(int i = str.length(); i >=0; i--)
                {
                stringToReturn += str.charAt(i);
                System.out.println(str.charAt(i));                
                }
   

That's the bit of code causes your exception. String index start from 0 to String.length() -1, and you pass String.length will result index out of bound exception.