toCharArray() How it works ?

[Austin]

Guys , i wud like to know how exactly toCharArray works in java. Like an algorithm of its function. I dont want its application, just the process behind it. What it does to the invoking string?

[sehudson]

the toCharArray method returns an Object of type charArray.
For instance:

String message = "abc";

char[] convertedString = message.toCharArray();

This will yield you a char array with 3 elements.
The 0th element will be: convertedString[0]='a';
The 1st element will be: convertedString[1]='b';
The 2nd element will be: convertedString[2]='c';

So most of the time you will be using the toCharArrayMethod to take a String and get an array of characters as output.
Does that help?

Maybe look at the javaDoc for a String if you need specifics, there are ton's of examples on the web.

[crikey]

public char[] toCharArray(String input){
char array = new char[input.length()];
for (int i = 0; i <= input.length() ; i++) {
array[i] = input.charAt(i);
}
}

[sehudson]

public char[] toCharArray(String input){
char array = new char[input.length()];
for (int i = 0; i <= input.length() ; i++) {
array[i] = input.charAt(i);
}
}

I think you have a few issues, for one you are missing the return statement. Hows this:

    public char[] toCharArray(String input) {
        int size = input.length();
        char[] returnedArray = new char[size];
        for (int i = 0; i < size; i++) {
            returnedArray[i] = input.charAt(i);
        }
        return returnedArray;
    }

[Norm]

What it does to the invoking string?

It does NOTHING to the String. Strings are immutable.

[sunde887]

It basically can be thought of as looking like this

public class String{
  char[] info;
  public char[] toCharArray(){
    return Arrays.copyOf(info, info.length);
  }
}

The exact code is going to different, but somewhat similar.

[Tolls]

Well, the exact code (from the src for String in the JDK) is:

    public char[] toCharArray() {
	char result[] = new char[count];
	getChars(0, count, result, 0);
	return result;
    }

where getChars does:

    public void getChars(int srcBegin, int srcEnd, char dst[], int dstBegin) {
        if (srcBegin < 0) {
            throw new StringIndexOutOfBoundsException(srcBegin);
        }
        if (srcEnd > count) {
            throw new StringIndexOutOfBoundsException(srcEnd);
        }
        if (srcBegin > srcEnd) {
            throw new StringIndexOutOfBoundsException(srcEnd - srcBegin);
        }
        System.arraycopy(value, offset + srcBegin, dst, dstBegin,
             srcEnd - srcBegin);
    }

Which you could have found for yourself just by looking in the source code...took me less than a minute. In fact took me longer to type this.

[sunde887]

I was being a bit lazy I suppose.

[Tolls]

Sorry, that last bit was directed at the OP...oops...

[stchman]

Guys , i wud like to know how exactly toCharArray works in java. Like an algorithm of its function. I dont want its application, just the process behind it. What it does to the invoking string?

You can download the source code for the String class.

java.lang: String.java

The toCharArray() method is actually very simple.

[Tolls]

And I just printed it out above...;)