Groovy example source code file (CallSiteWriter.java)

This example Groovy source code file (CallSiteWriter.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Groovy tags/keywords

argumentlistexpression, callsite_class, callsite_class, get_callsite_desc, get_callsite_method, hashset, interfacehelperclassnode, ljava/lang/object, ljava/lang/object, methodvisitor, methodvisitor, string, string, tupleexpression, util

The Groovy CallSiteWriter.java source code

/*
 * Copyright 2003-2009 the original author or authors.
 *
 * Licensed 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
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * 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.codehaus.groovy.classgen.asm;

import java.util.ArrayList;
import java.util.Collections;
import java.util.HashSet;
import java.util.LinkedList;
import java.util.List;

import org.codehaus.groovy.ast.ClassHelper;
import org.codehaus.groovy.ast.ClassNode;
import org.codehaus.groovy.ast.InterfaceHelperClassNode;
import org.codehaus.groovy.ast.expr.ArgumentListExpression;
import org.codehaus.groovy.ast.expr.CastExpression;
import org.codehaus.groovy.ast.expr.ClassExpression;
import org.codehaus.groovy.ast.expr.Expression;
import org.codehaus.groovy.ast.expr.TupleExpression;
import org.codehaus.groovy.classgen.AsmClassGenerator;
import org.codehaus.groovy.runtime.callsite.CallSite;
import org.objectweb.asm.Label;
import org.objectweb.asm.MethodVisitor;

import static org.objectweb.asm.Opcodes.*;

/**
 * This class represents non public API used by AsmClassGenerator. Don't
 * use this class in your code
 * @author Jochen Theodorou
 */
public class CallSiteWriter {
    
    private static final HashSet<String> names = new HashSet();
    private static final HashSet<String> basic = new HashSet();
    static {
        Collections.addAll(names, "plus", "minus", "multiply", "div", "compareTo", "or", "and", "xor", "intdiv", "mod", "leftShift", "rightShift", "rightShiftUnsigned");
        Collections.addAll(basic, "plus", "minus", "multiply", "div");
    }
    private static String [] sig = new String [255];
    private static String getCreateArraySignature(int numberOfArguments) {
        if (sig[numberOfArguments] == null) {
            StringBuilder sb = new StringBuilder("(");
            for (int i = 0; i != numberOfArguments; ++i) {
                sb.append("Ljava/lang/Object;");
            }
            sb.append(")[Ljava/lang/Object;");
            sig[numberOfArguments] = sb.toString();
        }
        return sig[numberOfArguments];
    }
    private final static int 
        MOD_PRIVSS = ACC_PRIVATE+ACC_STATIC+ACC_SYNTHETIC,
        MOD_PUBSS  = ACC_PUBLIC+ACC_STATIC+ACC_SYNTHETIC;
    private final static ClassNode CALLSITE_ARRAY_NODE = ClassHelper.make(CallSite[].class);
    private final static String 
        GET_CALLSITE_METHOD     = "$getCallSiteArray",
        CALLSITE_CLASS          = "org/codehaus/groovy/runtime/callsite/CallSite",
        CALLSITE_DESC           = "[Lorg/codehaus/groovy/runtime/callsite/CallSite;",
        GET_CALLSITE_DESC       = "()"+CALLSITE_DESC,
        CALLSITE_ARRAY_CLASS    = "org/codehaus/groovy/runtime/callsite/CallSiteArray",
        GET_CALLSITEARRAY_DESC  = "()Lorg/codehaus/groovy/runtime/callsite/CallSiteArray;",
        CALLSITE_FIELD          = "$callSiteArray",
        REF_CLASS               = "java/lang/ref/SoftReference",
        REF_DESC                = "L"+REF_CLASS+";",
        METHOD_OO_DESC          = "(Ljava/lang/Object;)Ljava/lang/Object;",
        CREATE_CSA_METHOD       = "$createCallSiteArray";
    public static final String CONSTRUCTOR = "<$constructor$>";
    
    private final List callSites = new ArrayList(32);
    private int callSiteArrayVarIndex;
    private WriterController controller;
    
    public CallSiteWriter(WriterController wc) {
        this.controller = wc;
        ClassNode node = controller.getClassNode();
        if(node instanceof InterfaceHelperClassNode) {
            InterfaceHelperClassNode ihcn = (InterfaceHelperClassNode) node;
            callSites.addAll(ihcn.getCallSites());
        }
    }
    
    public void makeSiteEntry() {
        if (controller.isNotClinit()) {
            controller.getMethodVisitor().visitMethodInsn(INVOKESTATIC, controller.getInternalClassName(), GET_CALLSITE_METHOD, GET_CALLSITE_DESC);
            controller.getOperandStack().push(CALLSITE_ARRAY_NODE);
            callSiteArrayVarIndex = controller.getCompileStack().defineTemporaryVariable("$local$callSiteArray", CALLSITE_ARRAY_NODE, true);
        }
    }
    
    public void generateCallSiteArray() {
        if (!controller.getClassNode().isInterface()) {
            controller.getClassVisitor().visitField(MOD_PRIVSS, CALLSITE_FIELD, REF_DESC, null, null);
            generateCreateCallSiteArray();
            generateGetCallSiteArray();
        }
    }

    private void generateGetCallSiteArray() {
        int visibility = (controller.getClassNode() instanceof InterfaceHelperClassNode) ? MOD_PUBSS : MOD_PRIVSS;
        MethodVisitor mv = controller.getClassVisitor().visitMethod(visibility, GET_CALLSITE_METHOD, GET_CALLSITE_DESC, null, null);
        controller.setMethodVisitor(mv);
        mv.visitCode();
        mv.visitFieldInsn(GETSTATIC, controller.getInternalClassName(), "$callSiteArray", "Ljava/lang/ref/SoftReference;");
        Label l0 = new Label();
        mv.visitJumpInsn(IFNULL, l0);
        mv.visitFieldInsn(GETSTATIC, controller.getInternalClassName(), "$callSiteArray", "Ljava/lang/ref/SoftReference;");
        mv.visitMethodInsn(INVOKEVIRTUAL, "java/lang/ref/SoftReference", "get", "()Ljava/lang/Object;");
        mv.visitTypeInsn(CHECKCAST, "org/codehaus/groovy/runtime/callsite/CallSiteArray");
        mv.visitInsn(DUP);
        mv.visitVarInsn(ASTORE, 0);
        Label l1 = new Label();
        mv.visitJumpInsn(IFNONNULL, l1);
        mv.visitLabel(l0);
        mv.visitMethodInsn(INVOKESTATIC, controller.getInternalClassName(), "$createCallSiteArray", "()Lorg/codehaus/groovy/runtime/callsite/CallSiteArray;");
        mv.visitVarInsn(ASTORE, 0);
        mv.visitTypeInsn(NEW, "java/lang/ref/SoftReference");
        mv.visitInsn(DUP);
        mv.visitVarInsn(ALOAD, 0);
        mv.visitMethodInsn(INVOKESPECIAL, "java/lang/ref/SoftReference", "<init>", "(Ljava/lang/Object;)V");
        mv.visitFieldInsn(PUTSTATIC, controller.getInternalClassName(), "$callSiteArray", "Ljava/lang/ref/SoftReference;");
        mv.visitLabel(l1);
        mv.visitVarInsn(ALOAD, 0);
        mv.visitFieldInsn(GETFIELD, "org/codehaus/groovy/runtime/callsite/CallSiteArray", "array", "[Lorg/codehaus/groovy/runtime/callsite/CallSite;");
        mv.visitInsn(ARETURN);
        mv.visitMaxs(0, 0);
        mv.visitEnd();
    }
        
    private void generateCreateCallSiteArray() { 
        List<String> callSiteInitMethods = new LinkedList(); 
        int index = 0; 
        int methodIndex = 0; 
        final int size = callSites.size(); 
        final int maxArrayInit = 5000; 
        // create array initialization methods
        while (index < size) { 
            methodIndex++; 
            String methodName = "$createCallSiteArray_" + methodIndex; 
            callSiteInitMethods.add(methodName); 
            MethodVisitor mv = controller.getClassVisitor().visitMethod(MOD_PRIVSS, methodName, "([Ljava/lang/String;)V", null, null);
            controller.setMethodVisitor(mv);
            mv.visitCode(); 
            int methodLimit = size; 
            // check if the next block is over the max allowed
            if ((methodLimit - index) > maxArrayInit) { 
                methodLimit = index + maxArrayInit; 
            } 
            for (; index < methodLimit; index++) { 
                mv.visitVarInsn(ALOAD, 0); 
                mv.visitLdcInsn(index); 
                mv.visitLdcInsn(callSites.get(index)); 
                mv.visitInsn(AASTORE); 
            } 
            mv.visitInsn(RETURN); 
            mv.visitMaxs(2,1); 
            mv.visitEnd(); 
        }
        // create base createCallSiteArray method
        MethodVisitor mv = controller.getClassVisitor().visitMethod(MOD_PRIVSS, CREATE_CSA_METHOD, GET_CALLSITEARRAY_DESC, null, null);
        controller.setMethodVisitor(mv);
        mv.visitCode(); 
        mv.visitLdcInsn(size); 
        mv.visitTypeInsn(ANEWARRAY, "java/lang/String"); 
        mv.visitVarInsn(ASTORE, 0); 
        for (String methodName : callSiteInitMethods) { 
            mv.visitVarInsn(ALOAD, 0); 
            mv.visitMethodInsn(INVOKESTATIC,controller.getInternalClassName(),methodName,"([Ljava/lang/String;)V"); 
        } 

        mv.visitTypeInsn(NEW, CALLSITE_ARRAY_CLASS); 
        mv.visitInsn(DUP); 
        controller.getAcg().visitClassExpression(new ClassExpression(controller.getClassNode())); 

        mv.visitVarInsn(ALOAD, 0); 

        mv.visitMethodInsn(INVOKESPECIAL, CALLSITE_ARRAY_CLASS, "<init>", "(Ljava/lang/Class;[Ljava/lang/String;)V");
        mv.visitInsn(ARETURN); 
        mv.visitMaxs(0,0); 
        mv.visitEnd(); 
    } 
    
    private int allocateIndex(String name) {
        callSites.add(name);
        return callSites.size()-1;
    }

    private void invokeSafe(boolean safe, String unsafeMethod, String safeMethod) {
        String method = unsafeMethod;
        if (safe) method = safeMethod;
        controller.getMethodVisitor().
            visitMethodInsn(INVOKEINTERFACE, CALLSITE_CLASS, method, METHOD_OO_DESC);
        controller.getOperandStack().replace(ClassHelper.OBJECT_TYPE);
    }

    public void prepareCallSite(String message) {
        MethodVisitor mv = controller.getMethodVisitor();
        if (controller.isNotClinit()) {
            mv.visitVarInsn(ALOAD, callSiteArrayVarIndex);
        } else {
            mv.visitMethodInsn(INVOKESTATIC, controller.getClassName(), GET_CALLSITE_METHOD, GET_CALLSITE_DESC);
        }
        final int index = allocateIndex(message);
        mv.visitLdcInsn(index);
        mv.visitInsn(AALOAD);
    }
    
    private void prepareSiteAndReceiver(Expression receiver, String methodName, boolean implicitThis) {
        prepareSiteAndReceiver(receiver, methodName, implicitThis, false);
    }
    
    private void prepareSiteAndReceiver(Expression receiver, String methodName, boolean implicitThis, boolean lhs) {
        //site
        prepareCallSite(methodName);

        // receiver
        CompileStack compileStack = controller.getCompileStack();
        compileStack.pushImplicitThis(implicitThis);
        compileStack.pushLHS(lhs);
        receiver.visit(controller.getAcg());
        controller.getOperandStack().box();
        compileStack.popLHS();
        compileStack.popImplicitThis();
    }
    
    private void visitBoxedArgument(Expression exp) {
        exp.visit(controller.getAcg());
        if (!(exp instanceof TupleExpression)) {
            // we are not in a tuple, so boxing might be missing for
            // this single argument call
            controller.getOperandStack().box();
        }
    }

    public void makeInvocation(Expression receiver, String message, Expression arguments) {
        OperandStack operandStack = controller.getOperandStack();
        int m1 = operandStack.getStackLength();
        //slow Path
        prepareSiteAndReceiver(receiver, message, false, controller.getCompileStack().isLHS());
        visitBoxedArgument(arguments);
        int m2 = operandStack.getStackLength();
        controller.getMethodVisitor().
            visitMethodInsn(INVOKEINTERFACE, "org/codehaus/groovy/runtime/callsite/CallSite", "call","(Ljava/lang/Object;Ljava/lang/Object;)Ljava/lang/Object;");
        operandStack.replace(ClassHelper.OBJECT_TYPE, m2-m1);
    }
    
    public void makeGroovyObjectGetPropertySite(Expression receiver, String methodName, boolean safe, boolean implicitThis) {
        prepareSiteAndReceiver(receiver, methodName, implicitThis);
        invokeSafe(safe, "callGroovyObjectGetProperty", "callGroovyObjectGetPropertySafe");
    }
    
    public void makeGetPropertySite(Expression receiver, String methodName, boolean safe, boolean implicitThis) {
        prepareSiteAndReceiver(receiver, methodName, implicitThis);
        invokeSafe(safe, "callGetProperty", "callGetPropertySafe");
    }
    
    public void makeCallSite(Expression receiver, String message, Expression arguments, boolean safe, boolean implicitThis, boolean callCurrent, boolean callStatic) {
        prepareSiteAndReceiver(receiver, message, implicitThis);

        CompileStack compileStack = controller.getCompileStack();
        compileStack.pushImplicitThis(implicitThis);
        compileStack.pushLHS(false);
        boolean constructor = message.equals(CONSTRUCTOR);
        OperandStack operandStack = controller.getOperandStack();
        
        // arguments
        boolean containsSpreadExpression = AsmClassGenerator.containsSpreadExpression(arguments);
        int numberOfArguments = containsSpreadExpression ? -1 : AsmClassGenerator.argumentSize(arguments);
        int operandsToReplace = 1;
        if (numberOfArguments > MethodCallerMultiAdapter.MAX_ARGS || containsSpreadExpression) {
            ArgumentListExpression ae;
            if (arguments instanceof ArgumentListExpression) {
                ae = (ArgumentListExpression) arguments;
            } else if (arguments instanceof TupleExpression) {
                TupleExpression te = (TupleExpression) arguments;
                ae = new ArgumentListExpression(te.getExpressions());
            } else {
                ae = new ArgumentListExpression();
                ae.addExpression(arguments);
            }
            controller.getCompileStack().pushImplicitThis(false);
            if (containsSpreadExpression) {
                numberOfArguments = -1;
                controller.getAcg().despreadList(ae.getExpressions(), true);
            } else {
                numberOfArguments = ae.getExpressions().size();
                for (int i = 0; i < numberOfArguments; i++) {
                    Expression argument = ae.getExpression(i);
                    argument.visit(controller.getAcg());
                    operandStack.box();
                    if (argument instanceof CastExpression) controller.getAcg().loadWrapper(argument);
                }
                operandsToReplace += numberOfArguments;
            }
            controller.getCompileStack().popImplicitThis();
        }
        controller.getCompileStack().popLHS();
        controller.getCompileStack().popImplicitThis();
        
        MethodVisitor mv = controller.getMethodVisitor();
        
        if (numberOfArguments > 4) {
            final String createArraySignature = getCreateArraySignature(numberOfArguments);
            mv.visitMethodInsn(INVOKESTATIC, "org/codehaus/groovy/runtime/ArrayUtil", "createArray", createArraySignature);
            //TODO: use pregenerated Object[]
            operandStack.replace(ClassHelper.OBJECT_TYPE.makeArray(),numberOfArguments);
            operandsToReplace = operandsToReplace-numberOfArguments+1;
        }

        final String desc = getDescForParamNum(numberOfArguments);
        if (callStatic) {
            mv.visitMethodInsn(INVOKEINTERFACE, CALLSITE_CLASS, "callStatic", "(Ljava/lang/Class;" + desc);
        } else if (constructor) {
            mv.visitMethodInsn(INVOKEINTERFACE, CALLSITE_CLASS, "callConstructor", "(Ljava/lang/Object;" + desc);
        } else if (callCurrent) {
            mv.visitMethodInsn(INVOKEINTERFACE, CALLSITE_CLASS, "callCurrent", "(Lgroovy/lang/GroovyObject;" + desc);
        } else if (safe) {
            mv.visitMethodInsn(INVOKEINTERFACE, CALLSITE_CLASS, "callSafe", "(Ljava/lang/Object;" + desc);
        } else {
            mv.visitMethodInsn(INVOKEINTERFACE, CALLSITE_CLASS, "call", "(Ljava/lang/Object;" + desc);
        }
        operandStack.replace(ClassHelper.OBJECT_TYPE,operandsToReplace);
    }
    
    private static String getDescForParamNum(int numberOfArguments) {
        switch (numberOfArguments) {
            case 0:
              return ")Ljava/lang/Object;";
            case 1:
              return "Ljava/lang/Object;)Ljava/lang/Object;";
            case 2:
                return "Ljava/lang/Object;Ljava/lang/Object;)Ljava/lang/Object;";
            case 3:
                return "Ljava/lang/Object;Ljava/lang/Object;Ljava/lang/Object;)Ljava/lang/Object;";
            case 4:
                return "Ljava/lang/Object;Ljava/lang/Object;Ljava/lang/Object;Ljava/lang/Object;)Ljava/lang/Object;";
            default:
                return "[Ljava/lang/Object;)Ljava/lang/Object;";
        }
    }

    public List<String> getCallSites() {
        return callSites;
    }

}