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

 *

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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).

 *

 * 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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 */

/**

 * @test

 * @summary Test direct and MethodHandle access to interface methods using invokespecial semantics

 * @compile SpecialInterfaceCallI4.jasm

 * @run main/othervm -Xint SpecialInterfaceCall

 * @run main/othervm -Xbatch -XX:+TieredCompilation -XX:TieredStopAtLevel=1 SpecialInterfaceCall

 * @run main/othervm -Xbatch -XX:-TieredCompilation SpecialInterfaceCall

 */

import java.lang.invoke.*;

public class SpecialInterfaceCall {

    interface I1 {

        default void pub_m() {};

        private void priv_m() {};

    }

    interface I2 extends I1 {

        // This needs to be a public method to avoid access control issues,

        // but logically we treat it as private and emulate invokespecial

        // using MethodHandles.

        default void pub_m() {};

        private void priv_m() {};

        static void invokeDirect(I2 i) {

            i.priv_m(); // generates invokespecial

        }

        static void invokeSpecialMH(I2 i) throws Throwable {

            // emulates behaviour of invokeDirect

            mh_I2_priv_m_from_I2.invokeExact(i);

        }

        // special case of invoking an Object method via an interface

        static void invokeSpecialObjectMH(I2 i) throws Throwable {

            // emulates invokespecial of I1.toString on i, which resolves

            // to Object.toString

            String s = (String) mh_I1_toString_from_I2.invokeExact(i);

        }

        // special case of invoking a final Object method via an interface

        static void invokeSpecialObjectFinalMH(I2 i) throws Throwable {

            // emulates invokespecial of I1.getClass on i, which resolves

            // to Object.getClass

            Class<?> c = (Class<?>) mh_I1_getClass_from_I2.invokeExact(i);

        }

    }

    interface I3 extends I2 {

        // Must take an I3 here rather than I2 else we get

        // WrongMethodTypeException: expected (I3)void but found (I2)void

        // Statically the receiver type is bounded by the caller type.

        static void invokeSpecialMH(I3 i) throws Throwable {

            // emulates an invokespecial of ((I2)i).pub_m()

            mh_I2_pub_m_from_I3.invokeExact(i);

        }

    }

    // This interface acts like I2 but we define directInvoke* methods

    // that we will rewrite the bytecode of to use invokespecial

    // (see SpecialInterfaceCallI4.jasm).

    interface I4 extends I1 {

        static void invokeDirect(I4 i) {

            // invokeSpecial Object.toString()

            throw new Error("Class file for I4 is not overwritten");

        }

        static void invokeDirectFinal(I4 i) {

            // invokeSpecial Object.getClass() - final method

            throw new Error("Class file for I4 is not overwritten");

        }

    }

    // Concrete classes

    static class C1 implements I1 { }

    static class C2 implements I2 { }

    static class C3 implements I3 { }

    static class C4 implements I4 { }

    // Classes that don't implement I2/I3 but do have a

    // priv_m/pub_m method in their hierarchy

    static class D1 implements I1 { }

    static class E {

        public void pub_m() {}

        private void priv_m() {}

    }

    // This MH acts like the direct invokespecial in I2.invokeDirect

    static final MethodHandle mh_I2_priv_m_from_I2;

    // This MH acts like an invokespecial of I2.pub_m from I3

    static final MethodHandle mh_I2_pub_m_from_I3;

    // This MH acts likes an invokespecial of I1.toString from I2

    static final MethodHandle mh_I1_toString_from_I2;

    // This MH acts likes an invokespecial of I1.getClass from I2

    static final MethodHandle mh_I1_getClass_from_I2;

    static {

        try {

            MethodType mt = MethodType.methodType(void.class);

            MethodHandles.Lookup lookup = MethodHandles.lookup();

            mh_I2_priv_m_from_I2 = lookup.findSpecial(I2.class, "priv_m", mt, I2.class);

            mh_I2_pub_m_from_I3 = lookup.findSpecial(I2.class, "pub_m", mt, I3.class);

            mt = MethodType.methodType(String.class);

            mh_I1_toString_from_I2 = lookup.findSpecial(I1.class, "toString", mt, I2.class);

            mt = MethodType.methodType(Class.class);

            mh_I1_getClass_from_I2 = lookup.findSpecial(I1.class, "getClass", mt, I2.class);

        } catch (Throwable e) {

            throw new Error(e);

        }

    }

    static void runPositiveTests() {

        shouldNotThrow(() -> I2.invokeDirect(new C2()));

        shouldNotThrow(() -> I2.invokeDirect(new C3()));

        shouldNotThrow(() -> I2.invokeSpecialMH(new C2()));

        shouldNotThrow(() -> I2.invokeSpecialMH(new C3()));

        shouldNotThrow(() -> I2.invokeSpecialObjectMH(new C2()));

        shouldNotThrow(() -> I2.invokeSpecialObjectMH(new C3()));

        shouldNotThrow(() -> I2.invokeSpecialObjectFinalMH(new C2()));

        shouldNotThrow(() -> I2.invokeSpecialObjectFinalMH(new C3()));

        shouldNotThrow(() -> I3.invokeSpecialMH(new C3()));

        shouldNotThrow(() -> I4.invokeDirect(new C4()));

        shouldNotThrow(() -> I4.invokeDirectFinal(new C4()));

    }

    static void runNegativeTests() {

        System.out.println("IAE I2.invokeDirect D1");

        shouldThrowIAE(() -> I2.invokeDirect(unsafeCastI2(new D1())));

        System.out.println("IAE I2.invokeDirect E");

        shouldThrowIAE(() -> I2.invokeDirect(unsafeCastI2(new E())));

        System.out.println("ICCE I2.invokeMH D1");

        shouldThrowICCE(() -> I2.invokeSpecialMH(unsafeCastI2(new D1())));

        System.out.println("ICCE I2.invokeMH E");

        shouldThrowICCE(() -> I2.invokeSpecialMH(unsafeCastI2(new E())));

        System.out.println("ICCE I3.invokeMH D1");

        shouldThrowICCE(() -> I3.invokeSpecialMH(unsafeCastI3(new D1())));

        System.out.println("ICCE I3.invokeMH E");

        shouldThrowICCE(() -> I3.invokeSpecialMH(unsafeCastI3(new E())));

        System.out.println("ICCE I3.invokeMH C2");

        shouldThrowICCE(() -> I3.invokeSpecialMH(unsafeCastI3(new C2())));

        System.out.println("ICCE I4.invokeDirect C1");

        shouldThrowIAE(() -> I4.invokeDirect(unsafeCastI4(new C1())));

        System.out.println("ICCE I4.invokeDirectFinal C1");

        shouldThrowIAE(() -> I4.invokeDirectFinal(unsafeCastI4(new C1())));

        System.out.println("ICCE I2.invokeObjectMH C1");

        shouldThrowICCE(() -> I2.invokeSpecialObjectMH(unsafeCastI2(new C1())));

        System.out.println("ICCE I2.invokeObjectFinalMH C1");

        shouldThrowICCE(() -> I2.invokeSpecialObjectFinalMH(unsafeCastI2(new C1())));

    }

    static void warmup() {

        for (int i = 0; i < 20_000; i++) {

            runPositiveTests();

        }

    }

    public static void main(String[] args) throws Throwable {

        System.out.println("UNRESOLVED:");

        runNegativeTests();

        runPositiveTests();

        System.out.println("RESOLVED:");

        runNegativeTests();

        System.out.println("WARMUP:");

        warmup();

        System.out.println("COMPILED:");

        runNegativeTests();

        runPositiveTests();

    }

    static interface Test {

        void run() throws Throwable;

    }

    static void shouldThrowICCE(Test t) {

        shouldThrow(IncompatibleClassChangeError.class,

                    "is not a subclass of caller class", t);

    }

    static void shouldThrowIAE(Test t) {

        shouldThrow(IllegalAccessError.class,

                    "must be the current class or a subtype of interface", t);

    }

    static void shouldThrow(Class<?> expectedError, String reason, Test t) {

        try {

            t.run();

        } catch (Throwable e) {

            if (expectedError.isInstance(e)) {

                if (e.getMessage().contains(reason)) {

                    // passed

                    System.out.println("Threw expected: " + e);

                    return;

                }

                else {

                    throw new AssertionError("Wrong exception reason: expected '" + reason

                                             + "', got '" + e.getMessage() + "'", e);

                }

            } else {

                String msg = String.format("Wrong exception thrown: expected=%s; thrown=%s",

                                           expectedError.getName(), e.getClass().getName());

                throw new AssertionError(msg, e);

            }

        }

        throw new AssertionError("No exception thrown: expected " + expectedError.getName());

    }

    static void shouldNotThrow(Test t) {

        try {

            t.run();

            // passed

        } catch (Throwable e) {

            throw new AssertionError("Exception was thrown: ", e);

        }

    }

    // Note: these unsafe casts are only possible for interface types

    static I2 unsafeCastI2(Object obj) {

        try {

            MethodHandle mh = MethodHandles.identity(Object.class);

            mh = MethodHandles.explicitCastArguments(mh, mh.type().changeReturnType(I2.class));

            return (I2)mh.invokeExact((Object) obj);

        } catch (Throwable e) {

            throw new Error(e);

        }

    }

    static I3 unsafeCastI3(Object obj) {

        try {

            MethodHandle mh = MethodHandles.identity(Object.class);

            mh = MethodHandles.explicitCastArguments(mh, mh.type().changeReturnType(I3.class));

            return (I3)mh.invokeExact((Object) obj);

        } catch (Throwable e) {

            throw new Error(e);

        }

    }

    static I4 unsafeCastI4(Object obj) {

        try {

            MethodHandle mh = MethodHandles.identity(Object.class);

            mh = MethodHandles.explicitCastArguments(mh, mh.type().changeReturnType(I4.class));

            return (I4)mh.invokeExact((Object) obj);

        } catch (Throwable e) {

            throw new Error(e);

        }

    }

}