Save custom object to file with ObjectInputStream and ObjectOutputStream

Description

Demo Code

import java.io.Serializable;

import java.io.*;

public class CardReader {
    public static void main(String[] args) {

        Card3 card = new Card3(12, Card3.SPADES);
        System.out.println("Card to write is: " + card);

        try {/*  w w w  .j  av a2  s  . c o  m*/
            FileOutputStream out = new FileOutputStream("card.out");
            ObjectOutputStream oos = new ObjectOutputStream(out);
            oos.writeObject(card);
            oos.flush();
        } catch (Exception e) {
            System.out.println("Problem serializing: " + e);
        }

        try {
            FileInputStream in = new FileInputStream("card.out");
            ObjectInputStream ois = new ObjectInputStream(in);
            card = (Card3) (ois.readObject());
        } catch (Exception e) {
            System.out.println("Problem serializing: " + e);
        }

        System.out.println("Card read is: " + card);

    }
}

class Card3 implements Serializable {
    private int suit = UNASSIGNED;
    private int number = UNASSIGNED;

    public final static int UNASSIGNED = -1;

    public final static int DIAMONDS = 1;
    public final static int CLUBS = 2;
    public final static int HEARTS = 3;
    public final static int SPADES = 4;

    public final static int ACE = 1;
    public final static int KING = 13;

    public Card3(int number, int suit) {
        if (isValidNumber(number)) {
            this.number = number;
        } else {
            //Error
        }

        if (isValidSuit(suit)) {
            this.suit = suit;
        } else {
            //Error
        }
    }

    public int getSuit() {
        return suit;
    }

    public int getNumber() {
        return number;
    }

    public static boolean isValidNumber(int number) {
        if (number >= ACE && number <= KING) {
            return true;
        } else {
            return false;
        }
    }

    public static boolean isValidSuit(int suit) {
        if (suit >= DIAMONDS && suit <= SPADES) {
            return true;
        } else {
            return false;
        }
    }

    public boolean equals(Object obj) {
        if (obj instanceof Card3) {
            Card3 card = (Card3) obj;
            if (card.getNumber() == this.number
                    && card.getSuit() == this.suit) {
                return true;
            } else {
                return false;
            }
        } else {
            return false;
        }
    }

    public int hashCode() {
        return number * suit;
    }

    public String toString() {
        return numberToString(this.number) + " of "
                + suitToString(this.suit);
    }

    public static String numberToString(int number) {
        String result = "";
        switch (number) {
        case ACE:
            result = "Ace";
            break;
        case 2:
            result = "Two";
            break;
        case 3:
            result = "Three";
            break;
        case 4:
            result = "Four";
            break;
        case 5:
            result = "Five";
            break;
        case 6:
            result = "Six";
            break;
        case 7:
            result = "Seven";
            break;
        case 8:
            result = "Eight";
            break;
        case 9:
            result = "Nine";
            break;
        case 10:
            result = "Ten";
            break;
        case 11:
            result = "Jack";
            break;
        case 12:
            result = "Queen";
            break;
        case KING:
            result = "King";
            break;
        case UNASSIGNED:
            result = "Invalid Number";
            break;
        }
        return result;
    }

    public static String suitToString(int suit) {
        String result = "";
        switch (suit) {
        case DIAMONDS:
            result = "Diamonds";
            break;
        case CLUBS:
            result = "Clubs";
            break;
        case HEARTS:
            result = "Hearts";
            break;
        case SPADES:
            result = "Spades";
            break;
        case UNASSIGNED:
            result = "Invalid Suit";
            break;
        }
        return result;
    }
}

/*
 * Copyright (c) 1995, 2008, Oracle and/or its affiliates. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *   - Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *
 *   - Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 *
 *   - Neither the name of Oracle or the names of its
 *     contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
Save custom object to file with ObjectInputStream and ObjectOutputStream - Java File Path IO

Description

Demo Code

Result

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