test/jdk/java/util/Calendar/bug4316678.java

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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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/*
 * @test
 * @bug 4316678 8347841
 * @summary test that Calendar's Serialization works correctly.
 * @run junit bug4316678
 */

import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.util.Calendar;
import java.util.GregorianCalendar;
import java.util.TimeZone;

import org.junit.jupiter.api.AfterAll;
import org.junit.jupiter.api.BeforeAll;
import org.junit.jupiter.api.Test;

import static org.junit.jupiter.api.Assertions.assertEquals;

public class bug4316678 {

    private static final String serializedData = "bug4316678.ser";

    // Save JVM default TimeZone
    private static final TimeZone savedTz = TimeZone.getDefault();

    // Set custom JVM default TimeZone
    @BeforeAll
    static void initAll() {
        TimeZone.setDefault(TimeZone.getTimeZone("America/Los_Angeles"));
    }

    // Restore JVM default Locale and TimeZone
    @AfterAll
    static void tearDownAll() {
        TimeZone.setDefault(savedTz);
    }

    // Test that a serialized GregorianCalendar has the expected values
    @Test
    public void serializationTest() throws IOException, ClassNotFoundException {
        GregorianCalendar gc1 = new GregorianCalendar(2000, Calendar.OCTOBER, 10);
        GregorianCalendar gc2;
        try (ObjectOutputStream out
                = new ObjectOutputStream(new FileOutputStream(serializedData))) {
            out.writeObject(gc1);
        }

        try (ObjectInputStream in = new ObjectInputStream(new FileInputStream(serializedData))) {
            gc2 = (GregorianCalendar)in.readObject();
        }

        gc1.set(Calendar.DATE, 16);
        gc2.set(Calendar.DATE, 16);
        assertEquals(gc2.getTime(), gc1.getTime(),
                "Times should be equal after serialization");
    }
}