ContactList.java

package Level_2.week_1.ContactListApplication;

/**
 * Created by pc on 08.08.2016.
 */
public class ContactList {

    private Contact[] contactList;
    private int busyPlaces;

    public void createContactList(){
        contactList = new Contact[100];
    }

    public boolean addContact(Contact contact){
        if (!contactValidation(contact)) {
            System.out.println("Wrong validation for contact with name : " + contact.getName());
            return false;
        }
        if (!checkUniqueName(contact)) {
            System.out.println(contact.getName() + " not unique");
            return false;
        }
        expandContactList();
        contactList[busyPlaces++] = contact;
        return true;
    }

    public boolean removeContact(String contactName){
        int contactPosition = findContactIndex(contactName);
        if (contactPosition == -1) {
            return false;
        }
        contactList[contactPosition] = null;
        busyPlaces--;
        if (contactPosition != contactList.length - 1) {
            System.arraycopy(contactList, contactPosition + 1, contactList, contactPosition, contactList.length - (contactPosition + 1)); //todo busyPlaces - (contactPosition + 1)
        }
        return true;
    }

    public boolean updateContactInfo(String contactName, String newContactData){
        if (!contactValidation(newContactData)) {
            System.out.println("contact with name: " + contactName + " doesn`t exist");
            return false;
        }

        if (!checkUniqueName(newContactData)) {
            System.out.println(newContactData + " not unique");
            return false;
        }

        int contactPosition = findContactIndex(contactName);
        if (contactPosition != -1) {
            contactList[contactPosition].setName(newContactData);
            return true;
        }
        return false;
    }

    public boolean checkUniqueName(Contact contact){
        return checkUniqueName(contact.getName());
    }

    public boolean checkUniqueName(String contactName){
        return findContactIndex(contactName) == -1;
    }

    public int findContactIndex(String contactName) {
            for (int i = 0; i < busyPlaces; i++) {
                if (contactList[i].getName().equals(contactName)) {
                    return i;
                }
            }
        return -1;
    }

    public Contact findContact(String contactName) {
            for (int i = 0; i < busyPlaces; i++)
                return contactList[i].getName().equals(contactName) ? contactList[i] : null;
        return null;
    }

    public void expandContactList(){
        if (busyPlaces >= contactList.length) {
            System.out.println("need to expand contact list");
            Contact[] newContactList = new Contact[contactList.length * 2];
            System.arraycopy(contactList, 0, newContactList, 0, contactList.length);
            contactList = newContactList;
        }
    }

    public String showLast(int count){

        StringBuilder resultContacts = new StringBuilder();
        int counter = 0;

        if (validateNumber(count)) {//todo change the condition, check for busyPlases 
            for (int i = busyPlaces - 1; i >= 0; i--) { //todo  for (int i = busyPlaces - 1; i > busyPlaces - count; i--)
                resultContacts.append(" " + i + "| " + contactList[i].toString() + "\n");
                counter++; //todo waste variable
                if (counter == count) {
                    return resultContacts.toString();
                    } else if (counter < count && i == 0) {
                    return String.valueOf(resultContacts.append("contactList contains less than" + count + " contacts: \n" + resultContacts));  //todo waste inspection, you already checked   if (validateNumber(count)) {
                    }
                }
            }
        return "number not valid";
    }

    public String showFirst(int count){
        StringBuilder resultContacts = new StringBuilder();

        if (validateNumber(count)) {
            for (int i = 0; i < count; i++) {

                if (contactList[i] == null) {
                    return String.valueOf(resultContacts.append(" contact not exist \n"));
                } else {
                    resultContacts.append(" " + i + "| " + contactList[i].toString() + "\n");
                }
            }
        }
        return "number not valid";
    }

    public String showALLContactList(){
        StringBuilder resultContacts = new StringBuilder();

        for (int i = 0; i < contactList.length; i++) {
            if (contactList[i] != null) {
                resultContacts.append(" " + i + "| "+ contactList[i].toString() + "\n");
            } else {
                resultContacts.append(i + "| contact not exist \n");
            }
        }
        return resultContacts.toString().trim();
    }

    public StringBuilder showContactsByOperator(String operator){
        StringBuilder result = new StringBuilder("");

        if (operator == "LIFE") {
            for (int j = 0; j < busyPlaces; j++) {
                if (contactList[j].getOperator() == "LIFE") {
                    result.append(contactList[j].toString() + " \n");
                }
            }
        } else {
            if (operator == "KIEVSTAR") {
                for (int j = 0; j < busyPlaces; j++) {
                    if (contactList[j].getOperator() == "KIEVSTAR") {
                        result.append(contactList[j].toString() + " \n");
                    }
                }
            } else {
                result.append("not exist");
            }
        }
        return result;
    }

    public boolean contactValidation(Contact contact){
        return (contact.getName() == null || contact.getSurname() == null) ? false :
                (!contact.getName().matches("^\\D*$")) || (!contact.getSurname().matches("^\\D*$")) ? false  : true;
    }

    public boolean contactValidation(String contactName){
        return (contactName == null) ? false : !(contactName.matches("^\\D*$")) ? false : true;
    }

    public boolean validateNumber(int value){
        if (0 < value && value <= contactList.length) {
            return true;
        }
        return false;
    }
}