ZCW-Arrays-StringArrayUtilities-BlueJ/StringArrayUtils.java

/**
 * Created by leon on 1/29/18.
 */
import java.util.Arrays;
public class StringArrayUtils {
    /**
     * @param array array of String objects
     * @return first element of specified array
     */ // TODO
    public static String getFirstElement(String[] array) {
        return array[0];
    }

    /**
     * @param array array of String objects
     * @return second element in specified array
     */
    public static String getSecondElement(String[] array) {
        return array[1];
    }

    /**
     * @param array array of String objects
     * @return last element in specified array
     */ // TODO
    public static String getLastElement(String[] array) {
        return array[array.length - 1];
    }

    /**
     * @param array array of String objects
     * @return second to last element in specified array
     */ // TODO
    public static String getSecondToLastElement(String[] array) {
        return array[array.length - 2];
    }

    /**
     * @param array array of String objects
     * @param value value to check array for
     * @return true if the array contains the specified `value`
     */ // TODO
    public static boolean contains(String[] array, String value) {

        boolean answer = false;
        for(String arr: array) {
            if (arr.equals(value)){
                answer = true;
                break;
            } 
        }
        return answer;
    }

    /**
     * @param array of String objects
     * @return an array with identical contents in reverse order
     */ // TODO
    public static String[] reverse(String[] array) {
        String[] answer = new String[array.length];
        int count = 0;

        for(int i = array.length - 1; i >= 0; i--){
            answer[count] = array[i];
            count++;
        }

        return answer;
    }

    /**
     * @param array array of String objects
     * @return true if the order of the array is the same backwards and forwards
     */ // TODO
    public static boolean isPalindromic(String[] array) {
        boolean answer = false;
        String[] flipped = reverse(array);

        if( Arrays.equals(array, flipped)){

            answer = true;}

        return answer;
    }

    /**
     * @param array array of String objects
     * @return true if each letter in the alphabet has been used in the array
     */ // TODO
    public static boolean isPangramic(String[] array) {
        String[] alpha = {"a","b","c","d","e","f","g","h","i","j","k","l","m","n","o","p","q","r","s","t","u","v","w","x","y","z"};
        String bigString = "";

        boolean result = true;
        //could be seperate method makeString(String[] arr)
        for(int i = 0; i<array.length;i++){
            bigString = bigString + array[i];
        }
        // could be seperate method backToArray(String string)
        String[] arrBig = new String[bigString.length()];
        for(int j = 0; j < arrBig.length; j++){
            arrBig[j]= (bigString.charAt(j)+"").toLowerCase();
        }

        for(int i = 0; i < alpha.length; i++){
            if(!contains(arrBig,alpha[i])){
                result = false;
                break;
            }
        }

        return result;
    }

    /**
     * @param array array of String objects
     * @param value value to check array for
     * @return number of occurrences the specified `value` has occurred
     */ // TODO
    public static int getNumberOfOccurrences(String[] array, String value) {
        int count = 0;
        for(int i = 0; i < array.length; i++){
            if(array[i].contains(value)){
                count++;
            }
        }

        return count;
    }

    /**
     * @param array         array of String objects
     * @param valueToRemove value to remove from array
     * @return array with identical contents excluding values of `value`
     */ // TODO
    public static String[] removeValue(String[] array, String valueToRemove) {
        //iterate over an array of strings
        // if array[i] !contains valueToRemove, add to new string
        // convert string to array
        // return new array
        String saveMe = "";

        for(int i = 0; i < array.length; i++){
            if(array[i] != valueToRemove){
                saveMe = saveMe + array[i] + " ";
            }
        }

        String[] answer = saveMe.split(" ", 0);

        return answer;
    }

    /**
     * @param array array of chars
     * @return array of Strings with consecutive duplicates removes
     */ // TODO
    public static String[] removeConsecutiveDuplicates(String[] array) {
        //create string to save needed values
        int count = 0;
        String saveMe = "";
        //loop array and compare array[i] and array[i+1]
        for(int i = 0; i < array.length; i++){
            
            if(count > 1 && array[i] == array[i+1]){
            saveMe = saveMe;
            } else if(count == 0 && array[i] == array[i + 1] && i < array.length - 2){
            count ++;
            saveMe = saveMe + array[i] + " ";
            }else if(array[i] != array[i -1]){
            saveMe = saveMe + array[i] + " ";
            }
        }
        String[] answer = saveMe.split(" ");
        return answer;
    }

    /**
     * @param array array of chars
     * @return array of Strings with each consecutive duplicate occurrence concatenated as a single string in an array of Strings
     */ // TODO
    public static String[] packConsecutiveDuplicates(String[] array) {
        int counter = getCount(array);
        String [] answer = new String[array.length - counter];
        String previous = array[0];
        answer[0] = array[0];
        int index = 0;
        
        for(int i = 1; i < array.length; i++) {
        if(array[i].equals(previous)){
        answer[index] += array[i];
        }else{
        index++;
        answer[index] = array[i];
        previous = array[i];
        }
        }
        
        return answer;
    }

    public static int getCount (String[] array) {
    
        int count = 0;
        for(int i = 0; i < array.length - 1; i++){
            if(array[i].equals(array[i + 1])){
                count++;
            }
        }

        return count;
    
    }
}