new to working with arrays

[jon Prais]

I have a problem and would like to know how best to approach
solving it.

I have an array of strings that need to be put in reverse order.

So I need to read the array the process it and reverse the strings..

any help would be great.

Please let me know if there is anything that needs to be cleared up

Thanks

[marc weber]

Welcome to JavaRanch!

What's your approach so far, and where are you having trouble?

[jon Prais]

I am also new to programming.

Since I don't know the length of the array I decided to you and arraylist(). From what I have read you need to dfine an array length and once it is set you cannot chat it without deleteing and redefining it.

Is that the right approach.

I look at the java code and think I could use some of these methods but not exactly sure how to approach the problem..

looking more or less for some psuedo code that will help me with thte thought process.

[Christophe Verré]

You should start by reading some basic material on arrays.
Sun Tutorial is a good place to start :
http://java.sun.com/docs/books/tutorial/java/data/arrays.html

[jon Prais]

thank you that is the info I was looking for to get me started

[ak pillai]

Java Collection framework is very powerful. It also has some utility classes for lot of algorithmic stuff like sorting, reversing, shuffling etc in java.util.Collections and java.util.Arrays. Here is a sample code:

import java.util.Arrays;
import java.util.Collections;
import java.util.List;

public class ReverseArray {
 
     public static void main(String[] args) {
         
         //if you have an array of String, convert it to a list
         
         String[] str = {"A", "B", "C", "D"};
         List list = Arrays.asList(str);
       
         System.out.println("before: " + list);
         Collections.reverse(list);
         System.out.println("after: " + list);  
     }
}

[Vijay Raj]

The OP wanted to reverse the string and not the array. This would reverse the string in the array.

 
String[] arr = {"One", "Two", "Three"};
int i = 0;
for(String str : arr)
{
 arr[i++] = new StringBuffer(str).reverse().toString();
}

Jon Prais, you need to study the language first and only then will you be able to sollve problems. I should not be posting solutions here but did it because I wanted to show that you can solve the problem without having the length of the array. You can get the length of the array using arrayName.length(i.e. arr.length from above example)

The above code uses the enhanced for-loop. You need Java 5 compiler.

regards,
vijay.

[Christophe Verré]

The above code uses the enhanced for-loop. You need Java 5 compiler

I would recommend to know how to do it the classic way.
Everybody should know how to get the size of an array.

[Jan Groth]

@Vijay

talking about java 5 - a StringBuilder would be more appropriate to use (new in J5), because it does not come with synchronisation-overhead...



regards,
jan