private String findKey(String word){
		
		StringBuilder key = new StringBuilder();
		String currentChar = "";
		
		for(int i=0;i<word.length();i++){
			
			currentChar = String.valueOf(word.charAt(i));
			
			if(CommonConstants.NUMBER_2.contains(currentChar)){
                key.append(2);
            }
            else if(CommonConstants.NUMBER_3.contains(currentChar)){
                key.append(3);
            }
            else if(CommonConstants.NUMBER_4.contains(currentChar)){
                key.append(4);
            }
            else if(CommonConstants.NUMBER_5.contains(currentChar)){
                key.append(5);
            }
            else if(CommonConstants.NUMBER_6.contains(currentChar)){
                key.append(6);
            }
            else if(CommonConstants.NUMBER_7.contains(currentChar)){
                key.append(7);
            }
            else if(CommonConstants.NUMBER_8.contains(currentChar)){
                key.append(8);
            }
            else if(CommonConstants.NUMBER_9.contains(currentChar)){
                key.append(9);
            }
		}
		return key.toString();
	}