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 * particular file as subject to the "Classpath" exception as provided

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 *

 * 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).

 *

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import java.util.Arrays;

import java.util.ConcurrentModificationException;

import java.util.HashMap;

import java.util.Hashtable;

import java.util.Iterator;

import java.util.LinkedHashMap;

import java.util.Map;

import java.util.function.BiFunction;

import org.testng.annotations.Test;

import org.testng.annotations.DataProvider;

/**

 * @test

 * @bug 8071667

 * @summary Ensure that ConcurrentModificationExceptions are thrown as specified from Map methods that accept Functions

 * @author bchristi

 * @build Defaults

 * @run testng FunctionalCMEs

 */

public class FunctionalCMEs {

    static final String KEY = "key";

    @DataProvider(name = "Maps", parallel = true)

    private static Iterator<Object[]> makeMaps() {

        return Arrays.asList(

                // Test maps that CME

                new Object[]{new HashMap<>(), true},

                new Object[]{new Hashtable<>(), true},

                new Object[]{new LinkedHashMap<>(), true},

                // Test default Map methods - no CME

                new Object[]{new Defaults.ExtendsAbstractMap<>(), false}

        ).iterator();

    }

    @Test(dataProvider = "Maps")

    public void testComputeIfAbsent(Map<String,String> map, boolean expectCME) {

        checkCME(() -> {

            map.computeIfAbsent(KEY, k -> {

                putToForceRehash(map);

                return "computedValue";

            });

        }, expectCME);

    }

    @Test(dataProvider = "Maps")

    public void testCompute(Map<String,String> map, boolean expectCME) {

        checkCME(() -> {

            map.compute(KEY, mkBiFunc(map));

        }, expectCME);

    }

    @Test(dataProvider = "Maps")

    public void testComputeWithKeyMapped(Map<String,String> map, boolean expectCME) {

        map.put(KEY, "firstValue");

        checkCME(() -> {

            map.compute(KEY, mkBiFunc(map));

        }, expectCME);

    }

    @Test(dataProvider = "Maps")

    public void testComputeIfPresent(Map<String,String> map, boolean expectCME) {

        map.put(KEY, "firstValue");

        checkCME(() -> {

           map.computeIfPresent(KEY, mkBiFunc(map));

        }, expectCME);

    }

    @Test(dataProvider = "Maps")

    public void testMerge(Map<String,String> map, boolean expectCME) {

        map.put(KEY, "firstValue");

        checkCME(() -> {

            map.merge(KEY, "nextValue", mkBiFunc(map));

        }, expectCME);

    }

    @Test(dataProvider = "Maps")

    public void testForEach(Map<String,String> map, boolean ignored) {

        checkCME(() -> {

            map.put(KEY, "firstValue");

            putToForceRehash(map);

            map.forEach((k,v) -> {

                map.remove(KEY);

            });

        }, true);

    }

    @Test(dataProvider = "Maps")

    public void testReplaceAll(Map<String,String> map, boolean ignored) {

        checkCME(() -> {

            map.put(KEY, "firstValue");

            putToForceRehash(map);

            map.replaceAll((k,v) -> {

                map.remove(KEY);

                return "computedValue";

            });

        },true);

    }

    private static void checkCME(Runnable code, boolean expectCME) {

        try {

            code.run();

        } catch (ConcurrentModificationException cme) {

            if (expectCME) { return; } else { throw cme; }

        }

        if (expectCME) {

            throw new RuntimeException("Expected CME, but wasn't thrown");

        }

    }

    private static BiFunction<String,String,String> mkBiFunc(Map<String,String> map) {

        return (k,v) -> {

            putToForceRehash(map);

            return "computedValue";

        };

    }

    private static void putToForceRehash(Map<String,String> map) {

        for (int i = 0; i < 64; ++i) {

            map.put(i + "", "value");

        }

    }

}