Reversing a string

[san ch]

Hi can some body help me with reversing a string
i.e if the string is "this is me" it should print it as
"me is this"

i trie dit by using stringtokenizer but messed it up terriblly

import java.util.*;
class StringEx 
{
public static void main(String[] args) 
{
String[] str = new String[100];
StringTokenizer st = new StringTokenizer("this is the string");
while (st.hasMoreTokens())
{
String s = st.nextToken();
str.concat(s);
}
 
System.out.println(str);

}
}  

thank you
san

[Vicken Karaoghlanian]

Try using the split("\\s") method to split the string into an array and then do a reverse loop through its elements.

You don't have to use the StringTokenizer class.
[ February 03, 2005: Message edited by: Vicken Karaoghlanian ]

[Layne Lund]

Originally posted by san ch:
i trie dit by using stringtokenizer but messed it up terriblly

What do you mean by this? Does the above program compile? If not, what errors do you get? If it does, what happens when you try to run it? It would help if you show us the output you get and explain how it differs from what you expect.

If you provide details like this, we will be more than happy to help you track down your problems and find solutions to them.

Keep Coding!

Layne

[Patrick Joseph]

as mentioned above, you can use the split() method to split the string based on the empty spaces.

 public class reverseTest {
public static void main(String[] args) {
String orig = "this is me";
String[] a = orig.split(" ");

System.out.println(orig);

if (a.length > 0) {
for (int i = a.length - 1; i >= 0; i--) {
System.out.print(a[i] + " ");
}
}
}
}
 

[san ch]

Hi

Sorry for not sharing the output details layne ,i didnt get how to go about with the string tokenizer .....so gave up on that .....

Thank you for your help PJ and vicken

san

[Shailesh Chandra]

san,

there is one more way... do the following

for example you have a string like


String str = "This is my String ";
StringBuffer sb = new StringBuffer(str);
str = ((StringBuffer)sb.reverse()).toString();


your string is now reversed

[pascal betz]

Shailesh :
your code does not produce the result San is looking for. output would be

gnirtS ym si sihT

instead of

String my is This

and the Cast to StringBuffer is not required. This will compile (but not produce what San is looking for :-) )

 
String str = "This is my String ";
StringBuffer sb = new StringBuffer(str);
str = sb.reverse().toString();
System.out.println(str);
 

pascal

[pascal betz]

oh and here is my try at it :-)

 
String in = "This is me here and there foo bar zaboong";
String out = "";
StringTokenizer st = new StringTokenizer(in, " ", true);
while(st.hasMoreTokens()) {
out = st.nextToken() + out;
}
System.out.println(out);
 

[Shailesh Chandra]

Originally posted by pascal betz:

your code does not produce the result San is looking for. output would be

Pascal,

Thanks for remindig me !!!

I skipped expected resulted as thread was subjected to reversing String !!! NOT reversing sentense

anyway thanks

Shailesh

[Raj Maheshwari]

Try This:
---------------------------------------
import java.util.*;

public class StringReverse {

public static void main(String args[]){

String myStr = "This is the string";
Vector v = new Vector();

System.out.println("Original String: "+myStr);

StringTokenizer st = new StringTokenizer(myStr);


while(st.hasMoreTokens()){

v.insertElementAt(st.nextToken(),0);
}

// at this point we have the words in a vector.

System.out.print("Reversed String: ");
for(int size=0;size<v.size();size++){
System.out.print(v.elementAt(size)+" ");
}


}

}

[san ch]

Thank you guys

because of your valuable posts i could learn different ways of doing it

San