org.ballerinalang.nativeimpl.jvm.methodvisitor.VisitInvokeDynamicInsn.java Source code

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Here is the source code for org.ballerinalang.nativeimpl.jvm.methodvisitor.VisitInvokeDynamicInsn.java

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/*
 * Copyright (c) 2019, WSO2 Inc. (http://www.wso2.org) All Rights Reserved.
 * <p>
 * WSO2 Inc. licenses this file to you under the Apache License,
 * Version 2.0 (the "License"); you may not use this file except
 * in compliance with the License.
 * You may obtain a copy of the License at
 * <p>
 * http://www.apache.org/licenses/LICENSE-2.0
 * <p>
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 **/
package org.ballerinalang.nativeimpl.jvm.methodvisitor;

import org.ballerinalang.jvm.scheduling.Strand;
import org.ballerinalang.jvm.values.ObjectValue;
import org.ballerinalang.nativeimpl.jvm.ASMUtil;
import org.ballerinalang.natives.annotations.Argument;
import org.ballerinalang.natives.annotations.BallerinaFunction;
import org.ballerinalang.natives.annotations.Receiver;
import org.objectweb.asm.Handle;
import org.objectweb.asm.MethodVisitor;
import org.objectweb.asm.Opcodes;
import org.objectweb.asm.Type;

import static org.ballerinalang.model.types.TypeKind.INT;
import static org.ballerinalang.model.types.TypeKind.OBJECT;
import static org.ballerinalang.model.types.TypeKind.STRING;
import static org.ballerinalang.nativeimpl.jvm.ASMUtil.FUNCTION_DESC;
import static org.ballerinalang.nativeimpl.jvm.ASMUtil.JVM_PKG_PATH;
import static org.ballerinalang.nativeimpl.jvm.ASMUtil.MAP_VALUE_DESC;
import static org.ballerinalang.nativeimpl.jvm.ASMUtil.METHOD_TYPE_DESC;
import static org.ballerinalang.nativeimpl.jvm.ASMUtil.METHOD_VISITOR;
import static org.ballerinalang.nativeimpl.jvm.ASMUtil.OBJECT_DESC;
import static org.ballerinalang.nativeimpl.jvm.ASMUtil.STRING_DESC;

/**
 * Code generation for invoke dynamic instruction.
 *
 * @since 0.995.0
 */
@BallerinaFunction(orgName = "ballerina", packageName = "jvm", functionName = "visitInvokeDynamicInsn", receiver = @Receiver(type = OBJECT, structType = METHOD_VISITOR, structPackage = JVM_PKG_PATH), args = {
        @Argument(name = "className", type = STRING), @Argument(name = "lambdaName", type = STRING),
        @Argument(name = "closureMapCount", type = INT) })
public class VisitInvokeDynamicInsn {

    public static void visitInvokeDynamicInsn(Strand strand, ObjectValue oMv, String className, String lambdaName,
            long mapsCount) {

        String mapDesc = getMapsDesc(mapsCount);

        //Function<Object[], Object> - create a dynamic lambda invocation with object[] param and returns object
        MethodVisitor mv = ASMUtil.getRefArgumentNativeData(oMv);
        Handle handle = new Handle(Opcodes.H_INVOKESTATIC, "java/lang/invoke/LambdaMetafactory", "metafactory",
                "(Ljava/lang/invoke/MethodHandles$Lookup;" + STRING_DESC + METHOD_TYPE_DESC + METHOD_TYPE_DESC
                        + "Ljava/lang/invoke/MethodHandle;" + METHOD_TYPE_DESC + ")Ljava/lang/invoke/CallSite;",
                false);

        mv.visitInvokeDynamicInsn("apply", "(" + mapDesc + ")" + FUNCTION_DESC, handle,
                new Object[] { Type.getType("(" + OBJECT_DESC + ")" + OBJECT_DESC),
                        new Handle(Opcodes.H_INVOKESTATIC, className, lambdaName,
                                "(" + mapDesc + "[" + OBJECT_DESC + ")" + OBJECT_DESC, false),
                        Type.getType("([" + OBJECT_DESC + ")" + OBJECT_DESC) });
    }

    private static String getMapsDesc(long count) {
        StringBuffer buf = new StringBuffer();
        for (long i = count; i > 0; i--) {
            buf.append(MAP_VALUE_DESC);
        }
        return buf.toString();
    }
}