StringUtilities.java

package com.zipcodewilmington.danny_do_better_exercises;

/**
 * Created by dan on 6/14/17.
 */
public class StringUtilities {
    /**
     * @return `Hello World` as a string
     */
    public static String getHelloWorld() {

        return "Hello World";
    }

    /**
     * @param firstSegment a string to be added to
     * @param secondSegment a string to add
     * @return the concatenation of two strings, `firstSegment`, and `secondSegment`
     */
    public static String concatenation(String firstSegment, String secondSegment){
        StringBuilder concat = new StringBuilder();
        concat.append(firstSegment).append(secondSegment);
        return concat.toString();
    }

    /**
     * @param firstSegment a string to be added to
     * @param secondSegment a string to add
     * @return the concatenation of an integer, `firstSegment`, and a String, `secondSegment`
     */
    public static String concatenation(int firstSegment, String secondSegment){
        StringBuilder concat = new StringBuilder();
        concat.append(firstSegment).append(secondSegment);
        return concat.toString();
    }

    /**
     * @param input a string to be manipulated
     * @return the first 3 characters of `input`
     */
    public static String getPrefix(String input){

        return input.substring(0,3);
    }

    /**
     * @param input a string to be manipulated
     * @return the last 3 characters of `input`
     */
    public static String getSuffix(String input){

        return input.substring(input.length() - 3, input.length());
    }

    /**
     * @param inputValue the value to be compared
     * @param comparableValue the value to be compared against
     * @return the equivalence of two strings, `inputValue` and `comparableValue`
     */
    public static Boolean compareTwoStrings(String inputValue, String comparableValue){

        return inputValue.equals(comparableValue);
    }

    /**
     * @param inputValue the value input from user
     * @return the middle character of `inputValue`
     */
    public static Character getMiddleCharacter(String inputValue){
        if (inputValue.length() % 2 == 0) {
            return inputValue.charAt((inputValue.length() / 2) - 1);
        }
        return inputValue.charAt(inputValue.length() / 2);
    }

    /**
     * @param spaceDelimitedString a string, representative of a sentence, containing spaces
     * @return the first sequence of characters
     */
    public static String getFirstWord(String spaceDelimitedString){
        for (int i = 0; i<spaceDelimitedString.length(); i++){
            if (spaceDelimitedString.charAt(i) == ' '){
                int chopper = i;
                return spaceDelimitedString.substring(0, chopper);
            }

        }
        return null;
    }

    /**
     * @param spaceDelimitedString a string delimited by spaces
     * @return the second word of a string delimited by spaces.
     */
    public static String getSecondWord(String spaceDelimitedString){
        int start = spaceDelimitedString.indexOf(' ') +1;
        //I spent way too long on this because I was trying way to hard to do it with loops (see my code for getFirstWord)
        //And I'm pretty sure this only works because the String in question only has 2 words.  But I'll take what I can get
        return spaceDelimitedString.substring(start, spaceDelimitedString.length());

    }

    /**
     * @param stringToReverse
     * @return an identical string with characters in reverse order.
     */
    public static String reverseTheTwo(String stringToReverse){
        StringBuilder answer = new StringBuilder();
        for (int i = stringToReverse.length() -1; i>=0; i--){
            answer.append(stringToReverse.charAt(i));
        }


        return answer.toString();
    }
}