ReplaceAllSpaces.java

public class ReplaceAllSpaces {

	public void replace(String s1, int length) {
		char[] chars = s1.toCharArray();
		int spaceCount = 0;
		for (int i = 0; i < length; i++) {
			if (chars[i] == ' ') {
				spaceCount++;
			}
		}
		int newLength = length + 2 * spaceCount;
		char [] charsNew = new char [newLength];
		for (int i = length - 1; i >= 0; i--) {
			if (chars[i] == ' ') {
				charsNew[newLength - 1] = '0';
				charsNew[newLength - 2] = '2';
				charsNew[newLength - 3] = '%';
				newLength = newLength - 3;
			} else {
//				System.out.println(chars[i]);
				charsNew[newLength - 1] = chars[i];
				newLength = newLength - 1;
			}
		}
		System.out.println("Output String : " + String.valueOf(charsNew));
	}

	public static void main(String args[]) {
		String s1 = "I am Sumit Jain";
		int trueLength = s1.length();
		System.out.println("Input String : " + s1);
		ReplaceAllSpaces r = new ReplaceAllSpaces();
		r.replace(s1, trueLength);
	}

}