Constructors

 * We can call another constructor by keyword : this();

package main;

public class Account {
    private String number;
    private double balance;
    private String customerName;
    private String customerEmailAddress;
    private String customerPhoneNumber;

    public Account() {
        this("11", 11, "Parvin", "parvin", "11");
        System.out.println("Empty constructor");
    }

    public Account(String number, double balance, String customerName, String customerEmailAddress, String customerPhoneNumber) {
        setNumber(number);
        setBalance(balance);
        setCustomerName(customerName);
        setCustomerEmailAddress(customerEmailAddress);
        setCustomerPhoneNumber(customerPhoneNumber);
    }

    public void deposit(double depositAmount) {
        this.balance += depositAmount;
        System.out.println("Deposit of " + depositAmount + " made. New balance is " + this.balance);
    }

    public void withdrawal(double withdrawalAmount) {
        if (this.balance - withdrawalAmount < 0) {
            System.out.println("Only " + this.balance + " available. Withdrawal not processed");
        } else {
            this.balance -= withdrawalAmount;
            System.out.println("Withdrawal of " + withdrawalAmount + " processed. Remaining balance = " + this.balance);
        }
    }

    public String getNumber() {
        return number;
    }

    public void setNumber(String number) {
        this.number = number;
    }

    public double getBalance() {
        return balance;
    }

    public void setBalance(double balance) {
        this.balance = balance;
    }

    public String getCustomerName() {
        return customerName;
    }

    public void setCustomerName(String customerName) {
        this.customerName = customerName;
    }

    public String getCustomerEmailAddress() {
        return customerEmailAddress;
    }

    public void setCustomerEmailAddress(String customerEmailAddress) {
        this.customerEmailAddress = customerEmailAddress;
    }

    public String getCustomerPhoneNumber() {
        return customerPhoneNumber;
    }

    public void setCustomerPhoneNumber(String customerPhoneNumber) {
        this.customerPhoneNumber = customerPhoneNumber;
    }

    @Override
    public String toString() {
        return "Account{" +
                "number='" + number + '\'' +
                ", balance=" + balance +
                ", customerName='" + customerName + '\'' +
                ", customerEmailAddress='" + customerEmailAddress + '\'' +
                ", customerPhoneNumber='" + customerPhoneNumber + '\'' +
                '}';
    }
}

Constructors Bad Example

package main;

public class Rectangle {
    private int x;
    private int y;
    private int width;
    private int height;

    public Rectangle() {
        this.x = 0;
        this.y = 0;
        this.width = 0;
        this.height = 0;
    }

    public Rectangle(int width, int height) {
        this.x = 0;
        this.y = 0;
        this.width = width;
        this.height = height;
    }

    public Rectangle(int x, int y, int width, int height) {
        this.x = x;
        this.y = y;
        this.width = width;
        this.height = height;
    }
}

Constructors Good Example

package main;

public class Rectangle {
    private int x;
    private int y;
    private int width;
    private int height;

    public Rectangle() {
        this(0, 0);
    }

    public Rectangle(int width, int height) {
        this(0, 0, width, height);
    }

    public Rectangle(int x, int y, int width, int height) {
        this.x = x;
        this.y = y;
        this.width = width;
        this.height = height;
    }
}