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 * 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.

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package p;

import java.lang.invoke.MethodHandle;

import java.lang.invoke.MethodHandles;

import java.lang.invoke.MethodHandles.Lookup;

import java.lang.reflect.Modifier;

import static java.lang.invoke.MethodHandles.Lookup.*;

import org.testng.annotations.BeforeTest;

import org.testng.annotations.Test;

import static org.testng.Assert.*;

/**

 * Unit tests for MethodHandles.privateLookupIn

 */

@Test

public class PrivateLookupInTests {

    /**

     * A public and non-public types in the test module but in a different

     * package to the test class.

     *

     * package p.internal;

     * public class PublicType {

     * }

     *

     * package p.internal;

     * class NonPublicType {

     *     private static final Object obj = ...

     * }

     */

    private Class<?> publicType;

    private Class<?> nonPublicType;

    // initialize and sanity check publicType/nonPublicType

    @BeforeTest

    public void init() throws Exception {

        publicType = Class.forName("p.internal.PublicType");

        assertTrue(this.getClass().getModule() == publicType.getModule());

        assertNotEquals(this.getClass().getPackageName(), publicType.getPackageName());

        assertTrue(Modifier.isPublic(publicType.getModifiers()));

        nonPublicType = Class.forName("p.internal.NonPublicType");

        assertTrue(this.getClass().getModule() == nonPublicType.getModule());

        assertNotEquals(this.getClass().getPackageName(), nonPublicType.getPackageName());

        assertFalse(Modifier.isPublic(nonPublicType.getModifiers()));

    }

    // Invoke MethodHandles.privateLookupIn with a full-power caller

    public void testAllAccessCallerSameModule() throws Throwable {

        Lookup lookup = MethodHandles.privateLookupIn(nonPublicType, MethodHandles.lookup());

        assertTrue(lookup.lookupClass() == nonPublicType);

        assertTrue(lookup.hasPrivateAccess());

        // get obj field

        MethodHandle mh = lookup.findStaticGetter(nonPublicType, "obj", Object.class);

        Object obj = mh.invokeExact();

    }

    // Invoke MethodHandles.privateLookupIn with a reduced-power caller

    public void testReducedAccessCallerSameModule() throws Throwable {

        Lookup caller = MethodHandles.lookup().dropLookupMode(PACKAGE);

        assertTrue((caller.lookupModes() & PRIVATE) == 0);

        assertTrue((caller.lookupModes() & PACKAGE) == 0);

        assertTrue((caller.lookupModes() & MODULE) != 0);

        Lookup lookup = MethodHandles.privateLookupIn(nonPublicType, caller);

        assertTrue(lookup.lookupClass() == nonPublicType);

        assertTrue(lookup.hasPrivateAccess());

        // use it

        MethodHandle mh = lookup.findStaticGetter(nonPublicType, "obj", Object.class);

        Object obj = mh.invokeExact();

    }

    // Invoke MethodHandles.privateLookupIn with the public lookup as caller

    @Test(expectedExceptions = {IllegalAccessException.class})

    public void testPublicLookupSameModule() throws Exception {

        Lookup caller = MethodHandles.publicLookup();

        Lookup lookup = MethodHandles.privateLookupIn(publicType, caller);

    }

    // test reads m1, open module m1 containing p1

    public void testTargetClassInOpenModule() throws Throwable {

        // m1/p1.Type

        Class<?> clazz = Class.forName("p1.Type");

        assertEquals(clazz.getModule().getName(), "m1");

        // ensure that this module reads m1

        Module thisModule = getClass().getModule();

        Module m1 = clazz.getModule();

        thisModule.addReads(clazz.getModule());

        assertTrue(m1.isOpen("p1", thisModule));

        Lookup lookup = MethodHandles.privateLookupIn(clazz, MethodHandles.lookup());

        assertTrue(lookup.lookupClass() == clazz);

        assertTrue(lookup.hasPrivateAccess());

        // get obj field

        MethodHandle mh = lookup.findStaticGetter(clazz, "obj", Object.class);

        Object obj = mh.invokeExact();

    }

    // test target class in unnamed module

    public void testTargetClassInUnnamedModule() throws Throwable {

        Class<?> clazz = Class.forName("Unnamed");

        assertFalse(clazz.getModule().isNamed());

        // thisModule does not read the unnamed module

        Module thisModule = getClass().getModule();

        assertFalse(thisModule.canRead(clazz.getModule()));

        try {

            MethodHandles.privateLookupIn(clazz, MethodHandles.lookup());

            assertTrue(false);

        } catch (IllegalAccessException expected) { }

        // thisModule reads the unnamed module

        thisModule.addReads(clazz.getModule());

        Lookup lookup = MethodHandles.privateLookupIn(clazz, MethodHandles.lookup());

        assertTrue(lookup.lookupClass() == clazz);

        assertTrue(lookup.hasPrivateAccess());

    }

    // test does not read m2, m2 opens p2 to test

    @Test(expectedExceptions = {IllegalAccessException.class})

    public void testCallerDoesNotRead() throws Throwable {

        // m2/p2.Type

        Class<?> clazz = Class.forName("p2.Type");

        assertEquals(clazz.getModule().getName(), "m2");

        Module thisModule = getClass().getModule();

        Module m2 = clazz.getModule();

        assertFalse(thisModule.canRead(m2));

        assertTrue(m2.isOpen("p2", thisModule));

        Lookup lookup = MethodHandles.privateLookupIn(clazz, MethodHandles.lookup());

    }

    // test reads m3, m3 does not open p3 to test

    @Test(expectedExceptions = {IllegalAccessException.class})

    public void testNotOpenToCaller() throws Throwable {

        // m3/p2.Type

        Class<?> clazz = Class.forName("p3.Type");

        assertEquals(clazz.getModule().getName(), "m3");

        Module thisModule = getClass().getModule();

        Module m3 = clazz.getModule();

        thisModule.addReads(clazz.getModule());

        assertFalse(m3.isOpen("p3", thisModule));

        Lookup lookup = MethodHandles.privateLookupIn(clazz, MethodHandles.lookup());

    }

    // Invoke MethodHandles.privateLookupIn with a primitive class

    @Test(expectedExceptions = {IllegalArgumentException.class})

    public void testPrimitiveClassAsTargetClass() throws Exception {

        MethodHandles.privateLookupIn(int.class, MethodHandles.lookup());

    }

    // Invoke MethodHandles.privateLookupIn with an array class

    @Test(expectedExceptions = {IllegalArgumentException.class})

    public void testArrayClassAsTargetClass() throws Exception {

        MethodHandles.privateLookupIn(PrivateLookupInTests[].class, MethodHandles.lookup());

    }

    // Invoke MethodHandles.privateLookupIn with a primitive array class

    @Test(expectedExceptions = {IllegalArgumentException.class})

    public void testPrimitiveArrayClassAsTargetClass() throws Exception {

        MethodHandles.privateLookupIn(int[].class, MethodHandles.lookup());

    }

    // Invoke MethodHandles.privateLookupIn with null

    @Test(expectedExceptions = {NullPointerException.class})

    public void testNullTargetClass() throws Exception {

        MethodHandles.privateLookupIn(null, MethodHandles.lookup());

    }

    // Invoke MethodHandles.privateLookupIn with null

    @Test(expectedExceptions = {NullPointerException.class})

    public void testNullCaller() throws Exception {

        MethodHandles.privateLookupIn(getClass(), null);

    }

}