/*

 * Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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 */

import java.io.*;

import java.lang.reflect.Field;

import org.testng.annotations.BeforeClass;

import org.testng.annotations.DataProvider;

import org.testng.annotations.Test;

import static org.testng.Assert.*;

/*

 * @test

 * @bug 8077559

 * @summary Tests Compact String. This one is testing

 *          if Compact String enable/disable VM Options is indeed working in String class,

 *          it's verified by testing if the VM option affect coder and

 *          COMPACT_STRINGS field in String class.

 * @modules java.base/java.lang:open

 * @run testng/othervm -XX:+CompactStrings -DCompactStringEnabled=true VMOptionsTest

 * @run testng/othervm -XX:-CompactStrings -DCompactStringEnabled=false VMOptionsTest

 */

public class VMOptionsTest {

    boolean compactStringEnabled;

    // corresponding "COMPACT_STRINGS" field in String class.

    Field COMPACT_STRINGS;

    // corresponding "coder" field in String class.

    Field coder;

    // corresponding coder type in String class.

    final byte LATIN1 = 0;

    final byte UTF16  = 1;

    @BeforeClass

    public void setUp() throws Exception {

        compactStringEnabled = Boolean.valueOf(System.getProperty("CompactStringEnabled", null));

        COMPACT_STRINGS = String.class.getDeclaredField("COMPACT_STRINGS");

        COMPACT_STRINGS.setAccessible(true);

        coder = String.class.getDeclaredField("coder");

        coder.setAccessible(true);

    }

    @DataProvider

    public Object[][] provider() {

        return new Object[][] {

                new Object[] {"", LATIN1},

                new Object[] {"abc", LATIN1},

                new Object[] {"A\uff21", UTF16},

                new Object[] {"\uff21\uff22", UTF16}

        };

    }

    /*

     * verify the coder field in String objects.

     */

    @Test(dataProvider = "provider")

    public void testCoder(String str, byte expected) throws Exception {

        byte c = (byte) coder.get(str);

        expected = compactStringEnabled ? expected : UTF16;

        assertEquals(c, expected);

    }

    /*

     * verify the COMPACT_STRINGS flag in String objects.

     */

    @Test(dataProvider = "provider")

    public void testCompactStringFlag(String str, byte ignore) throws Exception {

        assertTrue(COMPACT_STRINGS.get(str).equals(compactStringEnabled));

    }

}