ZCW-Arrays-StringArrayUtilities-BlueJ/StringArrayUtils.java

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

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

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

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

    /**
     * @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) {
        for(int i =0; i< array.length;i++)
        {
            if(array[i].equals(value))
            {return true;}
            

        }
        return false;

    }

    /** @param array of String objects
     * @return an array with identical contents in reverse order
     */ // TODO
    public static String[] reverse(String[] array) {
        String[] temp = new String[array.length]; 
        int  j =0;
        for(int i =array.length-1;i >= 0;i--)
        {
            temp[j] = array[i];
            j++;

        }
        return temp;

    }

    /**
     * @param array array of String objects
     * @return true if the order of the array is the same backwards and forwards
     */ 

    public static boolean isPalindromic(String[] array) {
        String[]  reverseArr = new String[array.length];
        reverseArr = reverse(array);

        for (int i=0;i < reverseArr.length;i++){
            if(!array[i].equalsIgnoreCase(reverseArr[i]))
            {
                return false;
            }
        }
        return true; 

    }

    /**
     * @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 alph = "abcdefghijklmnopqrstuvwxyz";
        StringBuilder build = new StringBuilder();
        int count =0;
        for(int i =0;i < array.length;i++)
        {
            build.append(array[i]);
        }
        String newStr = build.toString();
        for(int j =0; j < alph.length();j++)
        {
            int index = newStr.indexOf(alph.charAt(j));
            if( index == -1)
            {
                break;   
            }
            count = 1;    
        }
        if(count ==1)
            return true;
        else
            return false;

    }

    /**
     * @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].equalsIgnoreCase(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) {
        ArrayList <String >arrList = new ArrayList<String>();
        int j =0;
        int count =0;
        for(int i =0;i < array.length;i++)
        {

            if(!(array[i]).equals(valueToRemove))
            {    
                arrList.add(array[i]);
            }

        }
        String[] arrayNew = arrList.toArray(new String[0]);
        return arrayNew;
    }

    /**
     * @param array array of chars
     * @return array of Strings with consecutive duplicates removes
     */ // TODO*/
    public static String[] removeConsecutiveDuplicates(String[] array) {
        int k = 0;
        ArrayList<String> resultList = new ArrayList<String>();
        //resultList.add(array[0]);
        for(int i =0;i < array.length;i++)
        {
            if(!array[i].equals(array[i+1]))
            {
                resultList.add(array[i]);
            }

        }
        String[] newArray = resultList.toArray(new String[0]);
        return newArray;
    }

    /**
     * @param array array of chars
     * @return array of Strings with each consecutive duplicate occurrence concatenated as a single string in an array of Strings
     */ 
    public static String[] packConsecutiveDuplicates(String[] array) {
        ArrayList<String> list = new ArrayList<String>();
        //list.add(array[0]);
        //int k =0;
        StringBuilder build = new StringBuilder();
        for(int i =0;i <array.length;i++)
        {
            if(array[i].equalsIgnoreCase(array[i+1]))
            {
                build.append(array[i]);
                String str = build.toString();
                list.add(str);
                build = new StringBuilder();

            }
            else
            {
                build.append(array[i]);
            }
        }
        String[] newArray = list.toArray(new String[0]);
        return newArray;

    }
}