jdk/test/jdk/java/lang/invoke/FindAccessTest.java

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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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/* @test
 * @bug 8139885
 * @run junit/othervm -ea -esa test.java.lang.invoke.FindAccessTest
 */

package test.java.lang.invoke;

import java.lang.invoke.MethodHandle;
import java.lang.invoke.MethodHandles;
import java.lang.invoke.MethodHandles.Lookup;
import java.lang.invoke.MethodType;

import org.junit.jupiter.api.Test;

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

/**
 * Tests for Lookup.findClass/accessClass extensions added in JEP 274.
 */
public class FindAccessTest {

    static final Lookup LOOKUP = MethodHandles.lookup();

    @Test
    public void testFindSpecial() throws Throwable {
        FindSpecial.C c = new FindSpecial.C();
        assertEquals("I1.m", c.m());
        MethodType t = MethodType.methodType(String.class);
        MethodHandle ci1m = LOOKUP.findSpecial(FindSpecial.I1.class, "m", t, FindSpecial.C.class);
        assertEquals("I1.m", (String) ci1m.invoke(c));
    }

    @Test
    public void testFindSpecialAbstract() throws Throwable {
        FindSpecial.C c = new FindSpecial.C();
        assertEquals("q", c.q());
        MethodType t = MethodType.methodType(String.class);
        var thrown = assertThrows(IllegalAccessException.class,
                () -> LOOKUP.findSpecial(FindSpecial.I3.class, "q", t, FindSpecial.C.class));
        assertEquals(FindSpecial.ABSTRACT_ERROR, thrown.getMessage());
    }

    @Test
    public void testFindClassCNFE() throws ClassNotFoundException, IllegalAccessException {
        assertThrows(ClassNotFoundException.class, () -> LOOKUP.findClass("does.not.Exist"));
    }

    static class FindSpecial {

        interface I1 {
            default String m() {
                return "I1.m";
            }
        }

        interface I2 {
            default String m() {
                return "I2.m";
            }
        }

        interface I3 {
            String q();
        }

        static class C implements I1, I2, I3 {
            public String m() {
                return I1.super.m();
            }
            public String q() {
                return "q";
            }
        }

        static final String ABSTRACT_ERROR = "no such method: test.java.lang.invoke.FindAccessTest$FindSpecial$I3.q()String/invokeSpecial";

    }

}