All Downloads are FREE. Search and download functionalities are using the official Maven repository.

org.codehaus.groovy.classgen.Verifier Maven / Gradle / Ivy

The newest version!
/*
 * Copyright 2003-2014 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;

import groovy.lang.GroovyClassLoader;
import groovy.lang.GroovyObject;
import groovy.lang.MetaClass;

import org.codehaus.groovy.ast.*;
import org.codehaus.groovy.ast.expr.ArgumentListExpression;
import org.codehaus.groovy.ast.expr.BinaryExpression;
import org.codehaus.groovy.ast.expr.CastExpression;
import org.codehaus.groovy.ast.expr.ClosureExpression;
import org.codehaus.groovy.ast.expr.ConstantExpression;
import org.codehaus.groovy.ast.expr.ConstructorCallExpression;
import org.codehaus.groovy.ast.expr.DeclarationExpression;
import org.codehaus.groovy.ast.expr.Expression;
import org.codehaus.groovy.ast.expr.FieldExpression;
import org.codehaus.groovy.ast.expr.MethodCallExpression;
import org.codehaus.groovy.ast.expr.VariableExpression;
import org.codehaus.groovy.ast.stmt.BlockStatement;
import org.codehaus.groovy.ast.stmt.ExpressionStatement;
import org.codehaus.groovy.ast.stmt.ReturnStatement;
import org.codehaus.groovy.ast.stmt.Statement;
import org.codehaus.groovy.classgen.asm.BytecodeHelper;
import org.codehaus.groovy.classgen.asm.MopWriter;
import org.codehaus.groovy.classgen.asm.OptimizingStatementWriter.ClassNodeSkip;
import org.codehaus.groovy.classgen.asm.WriterController;
import org.codehaus.groovy.runtime.MetaClassHelper;
import org.codehaus.groovy.syntax.RuntimeParserException;
import org.codehaus.groovy.syntax.Token;
import org.codehaus.groovy.syntax.Types;
import org.codehaus.groovy.reflection.ClassInfo;
import org.codehaus.groovy.transform.trait.Traits;
import groovyjarjarasm.asm.Label;
import groovyjarjarasm.asm.MethodVisitor;
import groovyjarjarasm.asm.Opcodes;

import java.lang.reflect.Field;
import java.lang.reflect.Modifier;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Set;

import static org.codehaus.groovy.ast.tools.GeneralUtils.makeDescriptorWithoutReturnType;
import static org.codehaus.groovy.ast.tools.GenericsUtils.correctToGenericsSpec;
import static org.codehaus.groovy.ast.tools.GenericsUtils.createGenericsSpec;

/**
 * Verifies the AST node and adds any defaulted AST code before
 * bytecode generation occurs.
 *
 * @author James Strachan
 * @version $Revision$
 */
public class Verifier implements GroovyClassVisitor, Opcodes {

    public static final String STATIC_METACLASS_BOOL = "__$stMC";
    public static final String SWAP_INIT = "__$swapInit";
    public static final String INITIAL_EXPRESSION = "INITIAL_EXPRESSION";

    public static final String __TIMESTAMP = "__timeStamp";
    public static final String __TIMESTAMP__ = "__timeStamp__239_neverHappen";
    private static final Parameter[] INVOKE_METHOD_PARAMS = new Parameter[]{
            new Parameter(ClassHelper.STRING_TYPE, "method"),
            new Parameter(ClassHelper.OBJECT_TYPE, "arguments")
    };
    private static final Parameter[] SET_PROPERTY_PARAMS = new Parameter[]{
            new Parameter(ClassHelper.STRING_TYPE, "property"),
            new Parameter(ClassHelper.OBJECT_TYPE, "value")
    };
    private static final Parameter[] GET_PROPERTY_PARAMS = new Parameter[]{
            new Parameter(ClassHelper.STRING_TYPE, "property")
    };
    private static final Parameter[] SET_METACLASS_PARAMS = new Parameter[] {
            new Parameter(ClassHelper.METACLASS_TYPE, "mc")
    };

    private ClassNode classNode;
    private MethodNode methodNode;

    // GRECLIPSE: configuration options 
    public boolean inlineStaticFieldInitializersIntoClinit = true;
    public boolean inlineFieldInitializersIntoInit = true;
    
    public ClassNode getClassNode() {
        return classNode;
    }

    public MethodNode getMethodNode() {
        return methodNode;
    }

    private FieldNode setMetaClassFieldIfNotExists(ClassNode node, FieldNode metaClassField){
        if (metaClassField != null) return metaClassField;
        final String classInternalName = BytecodeHelper.getClassInternalName(node);
        metaClassField =
            node.addField("metaClass", ACC_PRIVATE | ACC_TRANSIENT | ACC_SYNTHETIC, ClassHelper.METACLASS_TYPE,
                    new BytecodeExpression(ClassHelper.METACLASS_TYPE) {
                public void visit(MethodVisitor mv) {
                    mv.visitVarInsn(ALOAD, 0);
                            mv.visitMethodInsn(INVOKEVIRTUAL, classInternalName, "$getStaticMetaClass", "()Lgroovy/lang/MetaClass;", false);
                        }});
        metaClassField.setSynthetic(true);
        return metaClassField;
    }

    private FieldNode getMetaClassField(ClassNode node) {
        FieldNode ret = node.getDeclaredField("metaClass");
        if (ret != null) {
        	ClassNode mcFieldType = ret.getType();
        	if (!mcFieldType.equals(ClassHelper.METACLASS_TYPE)) {
                throw new RuntimeParserException("The class " + node.getName() +
                        " cannot declare field 'metaClass' of type " + mcFieldType.getName() + " as it needs to be of " +
                        		"the type " + ClassHelper.METACLASS_TYPE.getName() + " for internal groovy purposes", ret);
        	}
        	return ret;
        }
        // GRECLIPSE: start
        /*old{
        ClassNode current = node;
        while (current != ClassHelper.OBJECT_TYPE) {
            current = current.getSuperClass();
            if (current == null) break;
            ret = current.getDeclaredField("metaClass");
            if (ret == null) continue;
            if (Modifier.isPrivate(ret.getModifiers())) continue;
            return ret;
        }*/
        // newcode
        ClassNode current = node.getSuperClass();
        // switched to equals from != but no longer sure if this is necessary
        while (current!=null && !current.equals(ClassHelper.OBJECT_TYPE)) {
            ret = current.getDeclaredField("metaClass");
            if (ret!=null && !Modifier.isPrivate(ret.getModifiers())) return ret;
            current = current.getSuperClass();
        }
        // end
        return null;
    }

    /**
     * add code to implement GroovyObject
     *
     * @param node
     */
    public void visitClass(final ClassNode node) {
        this.classNode = node;

        if (Traits.isTrait(node) // maybe possible to have this true in joint compilation mode
                || ((classNode.getModifiers() & Opcodes.ACC_INTERFACE) > 0)) {
            //interfaces have no constructors, but this code expects one,
            //so create a dummy and don't add it to the class node
            ConstructorNode dummy = new ConstructorNode(0,null);
            addInitialization(node, dummy);
            node.visitContents(this);
            if (classNode.getNodeMetaData(ClassNodeSkip.class)==null) {
                classNode.setNodeMetaData(ClassNodeSkip.class,true);
            }
            return;
        }

        ClassNode[] classNodes = classNode.getInterfaces();
        List interfaces = new ArrayList();
        for (ClassNode classNode : classNodes) {
            interfaces.add(classNode.getName());
        }
        Set interfaceSet = new HashSet(interfaces);
        if (interfaceSet.size() != interfaces.size()) {
            throw new RuntimeParserException("Duplicate interfaces in implements list: " + interfaces, classNode);
        }

        addDefaultParameterMethods(node);
        addDefaultParameterConstructors(node);

        final String classInternalName = BytecodeHelper.getClassInternalName(node);

        addStaticMetaClassField(node,classInternalName);

        boolean knownSpecialCase =
                node.isDerivedFrom(ClassHelper.GSTRING_TYPE)
                        || node.isDerivedFrom(ClassHelper.GROOVY_OBJECT_SUPPORT_TYPE);

        addFastPathHelperFieldsAndHelperMethod(node, classInternalName, knownSpecialCase);
        if (!knownSpecialCase) addGroovyObjectInterfaceAndMethods(node,classInternalName);

        addDefaultConstructor(node);

        // add a static timestamp field to the class
        if (!(node instanceof InnerClassNode)) addTimeStamp(node);

        addInitialization(node);
        checkReturnInObjectInitializer(node.getObjectInitializerStatements());
        node.getObjectInitializerStatements().clear();
        node.visitContents(this);
        checkForDuplicateMethods(node);
        addCovariantMethods(node);
    }

    private void checkForDuplicateMethods(ClassNode cn) {
        HashSet descriptors = new HashSet();
        for (MethodNode mn : cn.getMethods()) {
            if (mn.isSynthetic()) continue;
            String mySig = makeDescriptorWithoutReturnType(mn);
            if (descriptors.contains(mySig)) {
                if (mn.isScriptBody() || mySig.equals(scriptBodySignatureWithoutReturnType(cn))) {
                throw new RuntimeParserException("The method " + mn.getText() +
                            " is a duplicate of the one declared for this script's body code", mn);
                } else {
                    throw new RuntimeParserException("The method " + mn.getText() +
                        " duplicates another method of the same signature", mn);
            }
            }
            descriptors.add(mySig);
        }
    }

    private String scriptBodySignatureWithoutReturnType(ClassNode cn) {
        for (MethodNode mn : cn.getMethods()) {
            if (mn.isScriptBody()) return makeDescriptorWithoutReturnType(mn);
        }
        return null;
    }

    private FieldNode checkFieldDoesNotExist(ClassNode node, String fieldName) {
        FieldNode ret = node.getDeclaredField(fieldName);
        if (ret != null) {
            if (    Modifier.isPublic(ret.getModifiers()) &&
                    ret.getType().redirect()==ClassHelper.boolean_TYPE) {
                return ret;
            }
            throw new RuntimeParserException("The class " + node.getName() +
                    " cannot declare field '"+fieldName+"' as this" + 
                    " field is needed for internal groovy purposes", ret);
        }
        return null;
    }
    
    private void addFastPathHelperFieldsAndHelperMethod(ClassNode node, final String classInternalName, boolean knownSpecialCase) {
        if (node.getNodeMetaData(ClassNodeSkip.class)!=null) return;
        FieldNode stMCB = checkFieldDoesNotExist(node,STATIC_METACLASS_BOOL);
        if (stMCB==null) {
            stMCB = node.addField(
                    STATIC_METACLASS_BOOL, 
                    ACC_PUBLIC | ACC_STATIC | ACC_SYNTHETIC | ACC_TRANSIENT, 
                    ClassHelper.boolean_TYPE, null);
            stMCB.setSynthetic(true);
        }
    }

    protected void addDefaultConstructor(ClassNode node) {
        if (!node.getDeclaredConstructors().isEmpty()) return;
        
        BlockStatement empty = new BlockStatement();
        // GRECLIPSE: start:We don't want source locations for synthetic default constructors
        /*old{
        empty.setSourcePosition(node); 
        ConstructorNode constructor = new ConstructorNode(ACC_PUBLIC, empty);
        constructor.setSourcePosition(node);
        }*/
        // newcode
        ConstructorNode constructor = new ConstructorNode(ACC_PUBLIC, empty);
        // end
        constructor.setHasNoRealSourcePosition(true);
        node.addConstructor(constructor);
    }

    private static boolean isInnerClassOf(ClassNode a, ClassNode b) {
        if (a.redirect()==b) return true;
        if (b.redirect() instanceof InnerClassNode) return isInnerClassOf(a, b.redirect().getOuterClass());
        return false;
    }
    
    private void addStaticMetaClassField(final ClassNode node, final String classInternalName) {
        String _staticClassInfoFieldName = "$staticClassInfo";
        while (node.getDeclaredField(_staticClassInfoFieldName) != null)
            _staticClassInfoFieldName = _staticClassInfoFieldName + "$";
        final String staticMetaClassFieldName = _staticClassInfoFieldName;

        FieldNode staticMetaClassField = node.addField(staticMetaClassFieldName, ACC_PRIVATE|ACC_STATIC|ACC_SYNTHETIC, ClassHelper.make(ClassInfo.class,false), null);
        staticMetaClassField.setSynthetic(true);

        node.addSyntheticMethod(
                "$getStaticMetaClass",
                ACC_PROTECTED,
                ClassHelper.make(MetaClass.class),
                Parameter.EMPTY_ARRAY,
                ClassNode.EMPTY_ARRAY,
                new BytecodeSequence(new BytecodeInstruction(){
                    public void visit(MethodVisitor mv) {
                        mv.visitVarInsn(ALOAD, 0);
                        mv.visitMethodInsn(INVOKEVIRTUAL, "java/lang/Object", "getClass", "()Ljava/lang/Class;", false);
                        if (BytecodeHelper.isClassLiteralPossible(node) || BytecodeHelper.isSameCompilationUnit(classNode, node)) {
                            BytecodeHelper.visitClassLiteral(mv,node);
                        } else {
                            mv.visitMethodInsn(INVOKESTATIC, classInternalName, "$get$$class$" + classInternalName.replaceAll("\\/", "\\$"), "()Ljava/lang/Class;", false);
                        }
                        Label l1 = new Label();
                        mv.visitJumpInsn(IF_ACMPEQ, l1);

                        mv.visitVarInsn(ALOAD, 0);
                        mv.visitMethodInsn(INVOKESTATIC, "org/codehaus/groovy/runtime/ScriptBytecodeAdapter", "initMetaClass", "(Ljava/lang/Object;)Lgroovy/lang/MetaClass;", false);
                        mv.visitInsn(ARETURN);

                        mv.visitLabel(l1);
                        
                        mv.visitFieldInsn(GETSTATIC, classInternalName, staticMetaClassFieldName, "Lorg/codehaus/groovy/reflection/ClassInfo;");
                        mv.visitVarInsn(ASTORE, 1);
                        mv.visitVarInsn(ALOAD, 1);
                        Label l0 = new Label();
                        mv.visitJumpInsn(IFNONNULL, l0);

                        mv.visitVarInsn(ALOAD, 0);
                        mv.visitMethodInsn(INVOKEVIRTUAL, "java/lang/Object", "getClass", "()Ljava/lang/Class;", false);
                        mv.visitMethodInsn(INVOKESTATIC, "org/codehaus/groovy/reflection/ClassInfo", "getClassInfo", "(Ljava/lang/Class;)Lorg/codehaus/groovy/reflection/ClassInfo;", false);
                        mv.visitInsn(DUP);
                        mv.visitVarInsn(ASTORE, 1);
                        mv.visitFieldInsn(PUTSTATIC, classInternalName, staticMetaClassFieldName, "Lorg/codehaus/groovy/reflection/ClassInfo;");

                        mv.visitLabel(l0);

                        mv.visitVarInsn(ALOAD, 1);
                        mv.visitMethodInsn(INVOKEVIRTUAL, "org/codehaus/groovy/reflection/ClassInfo", "getMetaClass", "()Lgroovy/lang/MetaClass;", false);
                        mv.visitInsn(ARETURN);

                    }
                })
        );        
    }

    protected void addGroovyObjectInterfaceAndMethods(ClassNode node, final String classInternalName) {
        if (!node.isDerivedFromGroovyObject()) node.addInterface(ClassHelper.make(GroovyObject.class));
        FieldNode metaClassField = getMetaClassField(node);

        if (!node.hasMethod("getMetaClass", Parameter.EMPTY_ARRAY)) {
            metaClassField = setMetaClassFieldIfNotExists(node, metaClassField);
            addMethod(node,!Modifier.isAbstract(node.getModifiers()),
                    "getMetaClass",
                    ACC_PUBLIC,
                    ClassHelper.METACLASS_TYPE,
                    Parameter.EMPTY_ARRAY,
                    ClassNode.EMPTY_ARRAY,
                    new BytecodeSequence(new BytecodeInstruction() {
                public void visit(MethodVisitor mv) {
                    Label nullLabel = new Label();
                            /**
                             *  the code is:
                             *  if (this.metaClass==null) {
                             *      this.metaClass = this.$getStaticMetaClass
                             *      return this.metaClass
                             *  } else {
                             *      return this.metaClass    
                             *  }     
                             *  with the optimization that the result of the 
                             *  first this.metaClass is duped on the operand
                             *  stack and reused for the return in the else part
                             */                            
                    mv.visitVarInsn(ALOAD, 0);
                    mv.visitFieldInsn(GETFIELD, classInternalName, "metaClass", "Lgroovy/lang/MetaClass;");
                    mv.visitInsn(DUP);
                    mv.visitJumpInsn(IFNULL, nullLabel);
                    mv.visitInsn(ARETURN);

                    mv.visitLabel(nullLabel);
                    mv.visitInsn(POP);
                    mv.visitVarInsn(ALOAD, 0);
                    mv.visitInsn(DUP);
                    mv.visitMethodInsn(INVOKEVIRTUAL, classInternalName, "$getStaticMetaClass", "()Lgroovy/lang/MetaClass;", false);
                    mv.visitFieldInsn(PUTFIELD, classInternalName, "metaClass", "Lgroovy/lang/MetaClass;");
                    mv.visitVarInsn(ALOAD, 0);
                    mv.visitFieldInsn(GETFIELD, classInternalName, "metaClass", "Lgroovy/lang/MetaClass;");
                    mv.visitInsn(ARETURN);
                }
            })
            );
        }

        Parameter[] parameters = new Parameter[] { new Parameter(ClassHelper.METACLASS_TYPE, "mc") };
        if (!node.hasMethod("setMetaClass", parameters)) {
            metaClassField=setMetaClassFieldIfNotExists(node,metaClassField);
            Statement setMetaClassCode;                
            if (Modifier.isFinal(metaClassField.getModifiers())) {
                ConstantExpression text = new ConstantExpression("cannot set read-only meta class");
                ConstructorCallExpression cce = new ConstructorCallExpression(ClassHelper.make(IllegalArgumentException.class), text);
                setMetaClassCode = new ExpressionStatement(cce);
            } else {
                List list = new ArrayList();
                list.add (new BytecodeInstruction() {
                    public void visit(MethodVisitor mv) {
                        /**
                         * the code is (meta class is stored in 1):
                         * this.metaClass = <1>
                         */
                        mv.visitVarInsn(ALOAD, 0);
                        mv.visitVarInsn(ALOAD, 1);
                        mv.visitFieldInsn(PUTFIELD, classInternalName, 
                                "metaClass", "Lgroovy/lang/MetaClass;");
                        mv.visitInsn(RETURN);
                    }
                });
                setMetaClassCode = new BytecodeSequence(list);
            }
            
            addMethod(node,!Modifier.isAbstract(node.getModifiers()),
            		"setMetaClass",
                    ACC_PUBLIC, ClassHelper.VOID_TYPE,
                    SET_METACLASS_PARAMS, ClassNode.EMPTY_ARRAY,
                    setMetaClassCode 
            );
        }

        if (!node.hasMethod("invokeMethod",INVOKE_METHOD_PARAMS)) {
            VariableExpression vMethods = new VariableExpression("method");
            VariableExpression vArguments = new VariableExpression("arguments");
            VariableScope blockScope = new VariableScope();
            blockScope.putReferencedLocalVariable(vMethods);
            blockScope.putReferencedLocalVariable(vArguments);

            addMethod(node,!Modifier.isAbstract(node.getModifiers()),
                    "invokeMethod",
                    ACC_PUBLIC,
                    ClassHelper.OBJECT_TYPE, INVOKE_METHOD_PARAMS,
                    ClassNode.EMPTY_ARRAY,
                    new BytecodeSequence(new BytecodeInstruction() {
                public void visit(MethodVisitor mv) {
                    mv.visitVarInsn(ALOAD, 0);
                    mv.visitMethodInsn(INVOKEVIRTUAL, classInternalName, "getMetaClass", "()Lgroovy/lang/MetaClass;", false);
                    mv.visitVarInsn(ALOAD, 0);
                    mv.visitVarInsn(ALOAD, 1);
                    mv.visitVarInsn(ALOAD, 2);
                    mv.visitMethodInsn(INVOKEINTERFACE, "groovy/lang/MetaClass", "invokeMethod", "(Ljava/lang/Object;Ljava/lang/String;Ljava/lang/Object;)Ljava/lang/Object;", true);
                    mv.visitInsn(ARETURN);
                }
            })
            );
        }

        if (!node.hasMethod("getProperty", GET_PROPERTY_PARAMS)) {
        	addMethod(node,!Modifier.isAbstract(node.getModifiers()),
                    "getProperty",
                    ACC_PUBLIC,
                    ClassHelper.OBJECT_TYPE,
                    GET_PROPERTY_PARAMS,
                    ClassNode.EMPTY_ARRAY,
                    new BytecodeSequence(new BytecodeInstruction() {
                public void visit(MethodVisitor mv) {
                    mv.visitVarInsn(ALOAD, 0);
                            mv.visitMethodInsn(INVOKEVIRTUAL, classInternalName, "getMetaClass", "()Lgroovy/lang/MetaClass;", false);
                    mv.visitVarInsn(ALOAD, 0);
                    mv.visitVarInsn(ALOAD, 1);
                            mv.visitMethodInsn(INVOKEINTERFACE, "groovy/lang/MetaClass", "getProperty", "(Ljava/lang/Object;Ljava/lang/String;)Ljava/lang/Object;", true);
                    mv.visitInsn(ARETURN);
                }
            })
            );
        }

        if (!node.hasMethod("setProperty", SET_PROPERTY_PARAMS)) {
        	addMethod(node,!Modifier.isAbstract(node.getModifiers()),
                    "setProperty",
                    ACC_PUBLIC,
                    ClassHelper.VOID_TYPE,
                    SET_PROPERTY_PARAMS,
                    ClassNode.EMPTY_ARRAY,
                    new BytecodeSequence(new BytecodeInstruction() {
                public void visit(MethodVisitor mv) {
                    mv.visitVarInsn(ALOAD, 0);
                            mv.visitMethodInsn(INVOKEVIRTUAL, classInternalName, "getMetaClass", "()Lgroovy/lang/MetaClass;", false);
                    mv.visitVarInsn(ALOAD, 0);
                    mv.visitVarInsn(ALOAD, 1);
                    mv.visitVarInsn(ALOAD, 2);
                            mv.visitMethodInsn(INVOKEINTERFACE, "groovy/lang/MetaClass", "setProperty", "(Ljava/lang/Object;Ljava/lang/String;Ljava/lang/Object;)V", true);
                            mv.visitInsn(RETURN);
                        }
            })
            );
        }
    }

    /**
     * Helper method to add a new method to a ClassNode.  Depending on the shouldBeSynthetic flag the 
     * call will either be made to ClassNode.addSyntheticMethod() or ClassNode.addMethod(). If a non-synthetic method 
     * is to be added the ACC_SYNTHETIC modifier is removed if it has been accidentally supplied.
     */
    protected void addMethod(ClassNode node, boolean shouldBeSynthetic, String name, int modifiers, ClassNode returnType, Parameter[] parameters,
			ClassNode[] exceptions, Statement code) {
    	if (shouldBeSynthetic) {
    		node.addSyntheticMethod(name,modifiers,returnType,parameters,exceptions,code);
    	} else {
    		node.addMethod(name,modifiers&~ACC_SYNTHETIC,returnType,parameters,exceptions,code);    		
    	}
	}

	protected void addTimeStamp(ClassNode node) {
        if(node.getDeclaredField(Verifier.__TIMESTAMP) == null) { // in case if verifier visited the call already
        // GRECLIPSE: start: skip timestamp creation
//        FieldNode timeTagField = new FieldNode(
//                Verifier.__TIMESTAMP,
//                ACC_PUBLIC | ACC_STATIC | ACC_SYNTHETIC,
//                ClassHelper.Long_TYPE,
//                //"",
//                node,
//                new ConstantExpression(System.currentTimeMillis()));
//        // alternatively , FieldNode timeTagField = SourceUnit.createFieldNode("public static final long __timeStamp = " + System.currentTimeMillis() + "L");
//        timeTagField.setSynthetic(true);
//        node.addField(timeTagField);
//
//        timeTagField = new FieldNode(
//                Verifier.__TIMESTAMP__ + String.valueOf(System.currentTimeMillis()),
//                ACC_PUBLIC | ACC_STATIC | ACC_SYNTHETIC,
//                ClassHelper.Long_TYPE,
//                //"",
//                node,
//                new ConstantExpression((long) 0));
//        // alternatively , FieldNode timeTagField = SourceUnit.createFieldNode("public static final long __timeStamp = " + System.currentTimeMillis() + "L");
//        timeTagField.setSynthetic(true);
//        node.addField(timeTagField);
    }
    }

    private void checkReturnInObjectInitializer(List init) {
        CodeVisitorSupport cvs = new CodeVisitorSupport() {
            @Override
            public void visitClosureExpression(ClosureExpression expression) {
                // return is OK in closures in object initializers
            }

            public void visitReturnStatement(ReturnStatement statement) {
                throw new RuntimeParserException("'return' is not allowed in object initializer", statement);
            }
        };
        for (Iterator iterator = init.iterator(); iterator.hasNext();) {
            Statement stm = (Statement) iterator.next();
            stm.visit(cvs);
        }
    }

    public void visitConstructor(ConstructorNode node) {
        CodeVisitorSupport checkSuper = new CodeVisitorSupport() {
            boolean firstMethodCall = true;
            String type=null;
            public void visitMethodCallExpression(MethodCallExpression call) {
                if (!firstMethodCall) return;
                firstMethodCall = false;
                String name = call.getMethodAsString();
                // the name might be null if the method name is a GString for example
                if (name==null) return;
                if (!name.equals("super") && !name.equals("this")) return;
                type=name;
                call.getArguments().visit(this);
                type=null;
            }
            public void visitConstructorCallExpression(ConstructorCallExpression call) {
            	if (!call.isSpecialCall()) return;
            	type=call.getText();
            	call.getArguments().visit(this);
            	type=null;
            }
            public void visitVariableExpression(VariableExpression expression) {
                if (type==null) return;
                String name = expression.getName();
                if (!name.equals("this") && !name.equals("super")) return;
                throw new RuntimeParserException("cannot reference "+name+" inside of "+type+"(....) before supertype constructor has been called",expression);
            }
        };
        Statement s = node.getCode();
        if (s == null) {
            return;
        } else {
            s.visit(new VerifierCodeVisitor(this));
        }
        s.visit(checkSuper);
    }

    public void visitMethod(MethodNode node) {
    	//GROOVY-3712 - if it's an MOP method, it's an error as they aren't supposed to exist before ACG is invoked
        if(MopWriter.isMopMethod(node.getName())) {
    		throw new RuntimeParserException("Found unexpected MOP methods in the class node for " + classNode.getName() +
    				"(" + node.getName() + ")", classNode);
    	}
        this.methodNode = node;
        adjustTypesIfStaticMainMethod(node);
        addReturnIfNeeded(node);
        Statement statement;
        statement = node.getCode();
        if (statement!=null) statement.visit(new VerifierCodeVisitor(this));
    }
    
    private void adjustTypesIfStaticMainMethod(MethodNode node) {
        if (node.getName().equals("main") && node.isStatic()) {
            Parameter[] params = node.getParameters();
            if (params.length == 1) {
                Parameter param = params[0];
                if (param.getType() == null || param.getType()==ClassHelper.OBJECT_TYPE) {
                    param.setType(ClassHelper.STRING_TYPE.makeArray());
                    ClassNode returnType = node.getReturnType();
                    if(returnType == ClassHelper.OBJECT_TYPE) {
                        node.setReturnType(ClassHelper.VOID_TYPE);
                	}
            	}
        	}
    	}
    }

    protected void addReturnIfNeeded(MethodNode node) {
        ReturnAdder adder = new ReturnAdder();
        adder.visitMethod(node);
    }

    public void visitField(FieldNode node) {
    }
    
    private boolean methodNeedsReplacement(MethodNode m) {
        // no method found, we need to replace
        if (m==null) return true;
        // method is in current class, nothing to be done
        if (m.getDeclaringClass()==this.getClassNode()) return false;
        // do not overwrite final
        if ((m.getModifiers()&ACC_FINAL)!=0) return false;
        return true;
    }

    public void visitProperty(PropertyNode node) {
        String name = node.getName();
        FieldNode field = node.getField();
        int propNodeModifiers = node.getModifiers();

        String getterName = "get" + capitalize(name);
        String setterName = "set" + capitalize(name);

        // GROOVY-3726: clear volatile, transient modifiers so that they don't get applied to methods
        if((propNodeModifiers & Modifier.VOLATILE) != 0) {
        	propNodeModifiers = propNodeModifiers - Modifier.VOLATILE; 
        }
        if((propNodeModifiers & Modifier.TRANSIENT) != 0) {
        	propNodeModifiers = propNodeModifiers - Modifier.TRANSIENT; 
        }
        
        Statement getterBlock = node.getGetterBlock();
        if (getterBlock == null) {
            MethodNode getter = classNode.getGetterMethod(getterName);
            if(getter == null && ClassHelper.boolean_TYPE==node.getType()) {
            	String secondGetterName = "is" + capitalize(name);
            	getter = classNode.getGetterMethod(secondGetterName);
            }
            if (!node.isPrivate() && methodNeedsReplacement(getter)) {
                getterBlock = createGetterBlock(node, field);
            }
        }
        Statement setterBlock = node.getSetterBlock();
        if (setterBlock == null) {
            // 2nd arg false below: though not usual, allow setter with non-void return type
            MethodNode setter = classNode.getSetterMethod(setterName, false);
            if ( !node.isPrivate() && 
                 (propNodeModifiers & ACC_FINAL)==0 && 
                    methodNeedsReplacement(setter)) {
                setterBlock = createSetterBlock(node, field);
            }
        }

        if (getterBlock != null) {
            MethodNode getter =
                new MethodNode(getterName, propNodeModifiers, node.getType(), Parameter.EMPTY_ARRAY, ClassNode.EMPTY_ARRAY, getterBlock);
            getter.setSynthetic(true);
            addPropertyMethod(getter);
            visitMethod(getter);

            if (ClassHelper.boolean_TYPE==node.getType() || ClassHelper.Boolean_TYPE==node.getType()) {
                String secondGetterName = "is" + capitalize(name);
                MethodNode secondGetter =
                    new MethodNode(secondGetterName, propNodeModifiers, node.getType(), Parameter.EMPTY_ARRAY, ClassNode.EMPTY_ARRAY, getterBlock);
                secondGetter.setSynthetic(true);
                addPropertyMethod(secondGetter);
                visitMethod(secondGetter);
            }
        }
        if (setterBlock != null) {
            Parameter[] setterParameterTypes = { new Parameter(node.getType(), "value")};
            MethodNode setter =
                new MethodNode(setterName, propNodeModifiers, ClassHelper.VOID_TYPE, setterParameterTypes, ClassNode.EMPTY_ARRAY, setterBlock);
            setter.setSynthetic(true);
            addPropertyMethod(setter);
            visitMethod(setter);
        }
    }

    protected void addPropertyMethod(MethodNode method) {
    	classNode.addMethod(method);
        // GROOVY-4415 / GROOVY-4645: check that there's no abstract method which corresponds to this one
        List abstractMethods = classNode.getAbstractMethods();
        if (abstractMethods==null) return;
        String methodName = method.getName();
        Parameter[] parameters = method.getParameters();
        ClassNode methodReturnType = method.getReturnType();
        for (MethodNode node : abstractMethods) {
            if (!node.getDeclaringClass().equals(classNode)) continue;
            if (node.getName().equals(methodName)
                    && node.getParameters().length==parameters.length) {
                if (parameters.length==1) {
                    // setter
                    ClassNode abstractMethodParameterType = node.getParameters()[0].getType();
                    ClassNode methodParameterType = parameters[0].getType();
                    if (!methodParameterType.isDerivedFrom(abstractMethodParameterType) && !methodParameterType.implementsInterface(abstractMethodParameterType)) {
                        continue;
    				}
                }
                ClassNode nodeReturnType = node.getReturnType();
                if (!methodReturnType.isDerivedFrom(nodeReturnType) && !methodReturnType.implementsInterface(nodeReturnType)) {
                    continue;
                }
                // matching method, remove abstract status and use the same body
                node.setModifiers(node.getModifiers() ^ ACC_ABSTRACT);
                node.setCode(method.getCode());
            }
        }
    }
    
    // Implementation methods
    //-------------------------------------------------------------------------
    
    public interface DefaultArgsAction {
        void call(ArgumentListExpression arguments, Parameter[] newParams, MethodNode method);
    }
    
    /**
     * Creates a new helper method for each combination of default parameter expressions 
     */
    protected void addDefaultParameterMethods(final ClassNode node) {
        List methods = new ArrayList(node.getMethods());
        addDefaultParameters(methods, new DefaultArgsAction(){
            public void call(ArgumentListExpression arguments, Parameter[] newParams, MethodNode method) {
                final BlockStatement code = new BlockStatement();

                MethodNode newMethod = new MethodNode(method.getName(), method.getModifiers(), method.getReturnType(), newParams, method.getExceptions(), code);

                // GROOVY-5681 and GROOVY-5632
                for (Expression argument : arguments.getExpressions()) {
                    if (argument instanceof CastExpression) {
                        argument = ((CastExpression) argument).getExpression();
                    }
                    if (argument instanceof ConstructorCallExpression) {
                        ClassNode type = argument.getType();
                        if (type instanceof InnerClassNode && ((InnerClassNode) type).isAnonymous()) {
                            type.setEnclosingMethod(newMethod);
                        }
                    }

                    // check whether closure shared variables refer to params with default values (GROOVY-5632)
                    if (argument instanceof ClosureExpression)  {
                        final List newMethodNodeParameters = Arrays.asList(newParams);

                        CodeVisitorSupport visitor = new CodeVisitorSupport() {
                            @Override
                            public void visitVariableExpression(VariableExpression expression) {
                                Variable v = expression.getAccessedVariable();
                                if (!(v instanceof Parameter)) return;

                                Parameter param = (Parameter) v;
                                if (param.hasInitialExpression() && code.getVariableScope().getDeclaredVariable(param.getName()) == null && !newMethodNodeParameters.contains(param))  {

                                    VariableExpression localVariable = new VariableExpression(param.getName(), ClassHelper.makeReference());
                                    DeclarationExpression declarationExpression = new DeclarationExpression(localVariable, Token.newSymbol(Types.EQUAL, -1, -1), new ConstructorCallExpression(ClassHelper.makeReference(), param.getInitialExpression()));

                                    code.addStatement(new ExpressionStatement(declarationExpression));
                                    code.getVariableScope().putDeclaredVariable(localVariable);
                                }
                            }
                        };

                        visitor.visitClosureExpression((ClosureExpression) argument);
                    }
                }

                MethodCallExpression expression = new MethodCallExpression(VariableExpression.THIS_EXPRESSION, method.getName(), arguments);
                expression.setMethodTarget(method);
                expression.setImplicitThis(true);

                if (method.isVoidMethod()) {
                    code.addStatement(new ExpressionStatement(expression));
                } else {
                    code.addStatement(new ReturnStatement(expression));
                }

                List annotations = method.getAnnotations();
                if(annotations != null) {
                    newMethod.addAnnotations(annotations);
                }
                MethodNode oldMethod = node.getDeclaredMethod(method.getName(), newParams);
                if (oldMethod!=null) {
                    throw new RuntimeParserException(
                            "The method with default parameters \"" + method.getTypeDescriptor() +
                                    "\" defines a method \"" + newMethod.getTypeDescriptor() +
                            "\" that is already defined.",
                            method);
                }
                addPropertyMethod(newMethod);
                // GRECLIPSE start:
                // make sure that we know this is a variant of another method
                newMethod.setSourcePosition(method);
                newMethod.setNameStart(method.getNameStart());
                newMethod.setNameEnd(method.getNameEnd());
                newMethod.setOriginal(method);
                // GRECLIPSE end:
                newMethod.setGenericsTypes(method.getGenericsTypes());
            }
        });
    }
    
    protected void addDefaultParameterConstructors(final ClassNode node) {
        List methods = new ArrayList(node.getDeclaredConstructors());
        addDefaultParameters(methods, new DefaultArgsAction(){
            public void call(ArgumentListExpression arguments, Parameter[] newParams, MethodNode method) {
                ConstructorNode ctor = (ConstructorNode) method;
                ConstructorCallExpression expression = new ConstructorCallExpression(ClassNode.THIS, arguments);
                Statement code = new ExpressionStatement(expression);
                addConstructor(newParams, ctor, code, node);
            }
        });
    }

    protected void addConstructor(Parameter[] newParams, ConstructorNode ctor, Statement code, ClassNode node) {
        node.addConstructor(ctor.getModifiers(), newParams, ctor.getExceptions(), code);
    }

    /**
     * Creates a new helper method for each combination of default parameter expressions 
     */
    protected void addDefaultParameters(List methods, DefaultArgsAction action) {
        for (Iterator iter = methods.iterator(); iter.hasNext();) {
            MethodNode method = (MethodNode) iter.next();
            if (method.hasDefaultValue()) {
                addDefaultParameters(action, method);
            }
        }
    }

    protected void addDefaultParameters(DefaultArgsAction action, MethodNode method) {
                Parameter[] parameters = method.getParameters();
                int counter = 0;
                List paramValues = new ArrayList();
                int size = parameters.length;
                for (int i = size - 1; i >= 0; i--) {
                    Parameter parameter = parameters[i];
                    if (parameter != null && parameter.hasInitialExpression()) {
                        paramValues.add(Integer.valueOf(i));
                        paramValues.add(
                                new CastExpression(
                                        parameter.getType(),
                                        parameter.getInitialExpression()
                                )
                        );
                        counter++;
                    }
                }

                for (int j = 1; j <= counter; j++) {
                    Parameter[] newParams =  new Parameter[parameters.length - j];
                    ArgumentListExpression arguments = new ArgumentListExpression();
                    int index = 0;
                    int k = 1;
                    for (int i = 0; i < parameters.length; i++) {
                        if (k > counter - j && parameters[i] != null && parameters[i].hasInitialExpression()) {
                            arguments.addExpression(
                                    new CastExpression(
                                            parameters[i].getType(),
                                            parameters[i].getInitialExpression()
                                    )
                            );
                            k++;
                } else if (parameters[i] != null && parameters[i].hasInitialExpression()) {
                            newParams[index++] = parameters[i];
                            arguments.addExpression(
                                    new CastExpression(
                                            parameters[i].getType(),
                                            new VariableExpression(parameters[i].getName())
                                    )
                            );
                            k++;
                } else {
                            newParams[index++] = parameters[i];
                            arguments.addExpression(
                                    new CastExpression(
                                            parameters[i].getType(),
                                            new VariableExpression(parameters[i].getName())
                                    )
                            );
                        }
                    }
                    action.call(arguments,newParams,method);
                }
                
        for (Parameter parameter : parameters) {
            // remove default expression and store it as node metadata
            parameter.putNodeMetaData(Verifier.INITIAL_EXPRESSION, parameter.getInitialExpression());
            parameter.setInitialExpression(null);
                }
            }

    protected void addClosureCode(InnerClassNode node) {
        // add a new invoke
    }

    protected void addInitialization(final ClassNode node) {
        boolean addSwapInit = moveOptimizedConstantsInitialization(node);

        for (ConstructorNode cn : node.getDeclaredConstructors()) {
            addInitialization(node, cn);
        }
        
        if (addSwapInit) {
            BytecodeSequence seq = new BytecodeSequence(
                    new BytecodeInstruction() {
                        @Override
                        public void visit(MethodVisitor mv) {
                            mv.visitMethodInsn(INVOKESTATIC, BytecodeHelper.getClassInternalName(node), SWAP_INIT, "()V", false);
                        }
                    });
            
            List swapCall= new ArrayList(1);
            swapCall.add(seq);
            node.addStaticInitializerStatements(swapCall, true);
    	}
    }

    protected void addInitialization(ClassNode node, ConstructorNode constructorNode) {
        Statement firstStatement = constructorNode.getFirstStatement();
        // if some transformation decided to generate constructor then it probably knows who it does
        if (firstStatement instanceof BytecodeSequence)
            return;

        ConstructorCallExpression first = getFirstIfSpecialConstructorCall(firstStatement);
        
        // in case of this(...) let the other constructor do the init
        if (first!=null && (first.isThisCall())) return;
        
        List statements = new ArrayList();
        List staticStatements = new ArrayList();
        final boolean isEnum = node.isEnum();
        List initStmtsAfterEnumValuesInit = new ArrayList();
        Set explicitStaticPropsInEnum = new HashSet();
        if(isEnum) {
            for (PropertyNode propNode : node.getProperties()) {
        		if(!propNode.isSynthetic() && propNode.getField().isStatic()) {
        			explicitStaticPropsInEnum.add(propNode.getField().getName());
        		}
        	}
        	for (FieldNode fieldNode : node.getFields()) {
        		if(!fieldNode.isSynthetic() && fieldNode.isStatic() && fieldNode.getType() != node) {
        			explicitStaticPropsInEnum.add(fieldNode.getName());
        		}
        }
        }
        // GRECLIPSE - conditionally 'copy' the initializers into the ctors
        if (inlineFieldInitializersIntoInit) {
        // GRECLIPSE - end
	        for (FieldNode fn : node.getFields()) {
	            addFieldInitialization(statements, staticStatements, fn, isEnum,
	        			initStmtsAfterEnumValuesInit, explicitStaticPropsInEnum);
	        }
	    // GRECLIPSE - start
        }
        // GRECLIPSE - end
        statements.addAll(node.getObjectInitializerStatements());

            Statement code = constructorNode.getCode();
            BlockStatement block = new BlockStatement();
            List otherStatements = block.getStatements();
            if (code instanceof BlockStatement) {
                block = (BlockStatement) code;
                otherStatements=block.getStatements();
            } else if (code != null) {
                otherStatements.add(code);
            }
            if (!otherStatements.isEmpty()) {
                if (first!=null) {
                    // it is super(..) since this(..) is already covered
                    otherStatements.remove(0);
                    statements.add(0, firstStatement);
                } 
                Statement stmtThis$0 = getImplicitThis$0StmtIfInnerClass(otherStatements);
                if(stmtThis$0 != null) {
                	// since there can be field init statements that depend on method/property dispatching
                	// that uses this$0, it needs to bubble up before the super call itself (GROOVY-4471)
                	statements.add(0, stmtThis$0);
                }
                statements.addAll(otherStatements);
            }
            BlockStatement newBlock = new BlockStatement(statements, block.getVariableScope());
            newBlock.setSourcePosition(block);
            constructorNode.setCode(newBlock);

        if (!staticStatements.isEmpty()) {
        	if(isEnum) {
        		/*
        		 * GROOVY-3161: initialize statements for explicitly declared static fields 
        		 * inside an enum should come after enum values are initialized
        		 */
        		staticStatements.removeAll(initStmtsAfterEnumValuesInit);
        		node.addStaticInitializerStatements(staticStatements, true);
        		if(!initStmtsAfterEnumValuesInit.isEmpty()) {
        			node.positionStmtsAfterEnumInitStmts(initStmtsAfterEnumValuesInit);
        		}
        	} else {
        		node.addStaticInitializerStatements(staticStatements, true);
        	}
        }
    }
    
    /*
     *  when InnerClassVisitor adds this.this$0 = $p$n, it adds it as a BlockStatement having that 
    *  ExpressionStatement
     */
    private Statement getImplicitThis$0StmtIfInnerClass(List otherStatements) {
    	if(!(classNode instanceof InnerClassNode)) return null;
    	for(Statement stmt : otherStatements) {
    		if(stmt instanceof BlockStatement) {
    			List stmts = ((BlockStatement) stmt).getStatements();
    			for(Statement bstmt : stmts) {
    				if(bstmt instanceof ExpressionStatement) {
                        if (extractImplicitThis$0StmtIfInnerClassFromExpression(stmts, bstmt)) return bstmt;
                    }
                }
            } else if (stmt instanceof ExpressionStatement) {
                if (extractImplicitThis$0StmtIfInnerClassFromExpression(otherStatements, stmt)) return stmt;
            }
        }
        return null;
    }

    private boolean extractImplicitThis$0StmtIfInnerClassFromExpression(final List stmts, final Statement bstmt) {
    					Expression expr = ((ExpressionStatement)bstmt).getExpression();
    					if(expr instanceof BinaryExpression
    			                // GRECLIPSE: avoid transforming CompareIdentity and CompareToNull
    			                && expr.getClass() == BinaryExpression.class) {
    						Expression lExpr = ((BinaryExpression)expr).getLeftExpression();
    						if(lExpr instanceof FieldExpression) {
    							if("this$0".equals(((FieldExpression) lExpr).getFieldName())) {
    								stmts.remove(bstmt); // remove from here and let the caller reposition it
                    return true;
    			}
    		}
    	}
        return false;
    }
    
    private ConstructorCallExpression getFirstIfSpecialConstructorCall(Statement code) {
        if (code == null || !(code instanceof ExpressionStatement)) return null;

        Expression expression = ((ExpressionStatement)code).getExpression();
        if (!(expression instanceof ConstructorCallExpression)) return null;
        ConstructorCallExpression cce = (ConstructorCallExpression) expression;
        if (cce.isSpecialCall()) return cce;
        return null;
    }

    protected void addFieldInitialization(List list, List staticList, FieldNode fieldNode,
    		boolean isEnumClassNode, List initStmtsAfterEnumValuesInit, Set explicitStaticPropsInEnum) {
        Expression expression = fieldNode.getInitialExpression();
        if (expression != null) {
            final FieldExpression fe = new FieldExpression(fieldNode);
            if (fieldNode.getType().equals(ClassHelper.REFERENCE_TYPE) && ((fieldNode.getModifiers() & Opcodes.ACC_SYNTHETIC) != 0)) {
                fe.setUseReferenceDirectly(true);
            }
            ExpressionStatement statement =
                new ExpressionStatement(
                    new BinaryExpression(
                            fe,
                        Token.newSymbol(Types.EQUAL, fieldNode.getLineNumber(), fieldNode.getColumnNumber()),
                        expression));
            if (fieldNode.isStatic()) {
            	// GRECLIPSE: only conditionally 'move stuff around'
            	if (inlineStaticFieldInitializersIntoClinit) {
            	// end
		        	// GROOVY-3311: pre-defined constants added by groovy compiler for numbers/characters should be
		        	// initialized first so that code dependent on it does not see their values as empty
                	Expression initialValueExpression = fieldNode.getInitialValueExpression();
                	if (initialValueExpression instanceof ConstantExpression) {
                    	ConstantExpression cexp = (ConstantExpression) initialValueExpression;
                    	cexp = transformToPrimitiveConstantIfPossible(cexp);
                    if (fieldNode.isFinal() && ClassHelper.isStaticConstantInitializerType(cexp.getType()) && cexp.getType().equals(fieldNode.getType())) {
                    	    return; // GROOVY-5150: primitive type constants will be initialized directly
                    	}
		                staticList.add(0, statement);
		        	} else {
		                staticList.add(statement);
		        	}
		            fieldNode.setInitialValueExpression(null); // to avoid double initialization in case of several constructors
            	}
                /*
                 * If it is a statement for an explicitly declared static field inside an enum, store its
                 * reference. For enums, they need to be handled differently as such init statements should
                 * come after the enum values have been initialized inside  block. GROOVY-3161.
                 */
                if(isEnumClassNode && explicitStaticPropsInEnum.contains(fieldNode.getName())) {
                	initStmtsAfterEnumValuesInit.add(statement);
                }
            } else {
                list.add(statement);
            }
        }
    }

    /**
     * Capitalizes the start of the given bean property name
     */
    public static String capitalize(String name) {
        return MetaClassHelper.capitalize(name);
    }

    protected Statement createGetterBlock(PropertyNode propertyNode, final FieldNode field) {
        return new BytecodeSequence(new BytecodeInstruction(){
            public void visit(MethodVisitor mv) {
                if (field.isStatic()) {
                    mv.visitFieldInsn(GETSTATIC, BytecodeHelper.getClassInternalName(classNode), field.getName(), BytecodeHelper.getTypeDescription(field.getType()));
                } else {
                    mv.visitVarInsn(ALOAD, 0);
                    mv.visitFieldInsn(GETFIELD, BytecodeHelper.getClassInternalName(classNode), field.getName(), BytecodeHelper.getTypeDescription(field.getType()));
                }
                BytecodeHelper.doReturn(mv, field.getType());
            }
        });
    }

    protected Statement createSetterBlock(PropertyNode propertyNode, final FieldNode field) {
        return new BytecodeSequence(new BytecodeInstruction(){
            public void visit(MethodVisitor mv) {
                if (field.isStatic()) {
                    BytecodeHelper.load(mv, field.getType(), 0);
                    mv.visitFieldInsn(PUTSTATIC, BytecodeHelper.getClassInternalName(classNode), field.getName(), BytecodeHelper.getTypeDescription(field.getType()));
                } else {
                    mv.visitVarInsn(ALOAD, 0);
                    BytecodeHelper.load(mv, field.getType(), 1);
                    mv.visitFieldInsn(PUTFIELD, BytecodeHelper.getClassInternalName(classNode), field.getName(), BytecodeHelper.getTypeDescription(field.getType()));
                }
                mv.visitInsn(RETURN);
            }
        });
    }

    public void visitGenericType(GenericsType genericsType) {

    }

    public static long getTimestamp (Class clazz) {
        if (clazz.getClassLoader() instanceof GroovyClassLoader.InnerLoader) {
            GroovyClassLoader.InnerLoader innerLoader = (GroovyClassLoader.InnerLoader) clazz.getClassLoader();
            return innerLoader.getTimeStamp();
        }

        final Field[] fields = clazz.getFields();
        for (int i = 0; i != fields.length; ++i ) {
           if (Modifier.isStatic(fields[i].getModifiers())) {
               final String name = fields[i].getName();
               if (name.startsWith(__TIMESTAMP__)) {
                 try {
                     return Long.decode(name.substring(__TIMESTAMP__.length())).longValue();
                    } catch (NumberFormatException e) {
                     return Long.MAX_VALUE;
                 }
             }
           }
        }
        return Long.MAX_VALUE;
    }
    
    protected void addCovariantMethods(ClassNode classNode) {
        Map methodsToAdd = new HashMap();
        Map genericsSpec = new HashMap();

        // unimplemented abstract methods from interfaces
        Map abstractMethods = new HashMap();
        Map allInterfaceMethods = new HashMap();
        ClassNode[] interfaces = classNode.getInterfaces();
        for (ClassNode iface : interfaces) {
            Map ifaceMethodsMap = iface.getDeclaredMethodsMap();
            abstractMethods.putAll(ifaceMethodsMap);
            allInterfaceMethods.putAll(ifaceMethodsMap);
        }
        
        collectSuperInterfaceMethods(classNode, allInterfaceMethods);

        List declaredMethods = new ArrayList(classNode.getMethods());
        // remove all static, private and package private methods
        for (Iterator methodsIterator = declaredMethods.iterator(); methodsIterator.hasNext();) {
            MethodNode m = (MethodNode) methodsIterator.next();
            abstractMethods.remove(m.getTypeDescriptor());
            if (m.isStatic() || !(m.isPublic() || m.isProtected())) {
                methodsIterator.remove();
            } 
            MethodNode intfMethod = allInterfaceMethods.get(m.getTypeDescriptor());
            if(intfMethod != null && ((m.getModifiers() & ACC_SYNTHETIC) == 0) 
            		&& !m.isPublic() && !m.isStaticConstructor()) {
                throw new RuntimeParserException("The method " + m.getName() +
                        " should be public as it implements the corresponding method from interface " +
                        intfMethod.getDeclaringClass(), m);

            }
        }
        
        addCovariantMethods(classNode, declaredMethods, abstractMethods, methodsToAdd, genericsSpec);

        Map declaredMethodsMap = new HashMap();
        if (methodsToAdd.size()>0) {
            for (MethodNode mn : declaredMethods) {
                declaredMethodsMap.put(mn.getTypeDescriptor(), mn);
            }
        }
        
        for (Object o : methodsToAdd.entrySet()) {
            Map.Entry entry = (Map.Entry) o;
            MethodNode method = (MethodNode) entry.getValue();
            // we skip bridge methods implemented in current class already
            MethodNode mn = declaredMethodsMap.get(entry.getKey());
            if (mn!=null && mn.getDeclaringClass().equals(classNode)) continue;
            addPropertyMethod(method);
        }
    }
    
    private void collectSuperInterfaceMethods(ClassNode cn, Map allInterfaceMethods) {
    	List cnInterfaces = Arrays.asList(cn.getInterfaces());
    	ClassNode sn = cn.getSuperClass();
    	while(sn!=null && !sn.equals(ClassHelper.OBJECT_TYPE)) {
            ClassNode[] interfaces = sn.getInterfaces();
            for (ClassNode iface : interfaces) {
                if(!cnInterfaces.contains(iface)) {
                    Map ifaceMethodsMap = iface.getDeclaredMethodsMap();
                    allInterfaceMethods.putAll(ifaceMethodsMap);
                }
            }
            sn = sn.getSuperClass();
    	}
    }

    private void addCovariantMethods(ClassNode classNode, List declaredMethods, Map abstractMethods, Map methodsToAdd, Map oldGenericsSpec) {
        ClassNode sn = classNode.getUnresolvedSuperClass(false);
        
        if (sn!=null) {
            Map genericsSpec = createGenericsSpec(sn,oldGenericsSpec);
            List classMethods = sn.getMethods();
            // original class causing bridge methods for methods in super class
            for (Object declaredMethod : declaredMethods) {
                MethodNode method = (MethodNode) declaredMethod;
                if (method.isStatic()) continue;
                storeMissingCovariantMethods(classMethods,method,methodsToAdd,genericsSpec);
            }
            // super class causing bridge methods for abstract methods in original class
            if (!abstractMethods.isEmpty()) {
                for (Object classMethod : classMethods) {
                    MethodNode method = (MethodNode) classMethod;
                    if (method.isStatic()) continue;
                    storeMissingCovariantMethods(abstractMethods.values(),method,methodsToAdd,Collections.EMPTY_MAP);
                }
            }
            
            addCovariantMethods(sn.redirect(),declaredMethods,abstractMethods,methodsToAdd,genericsSpec);
        }
        
        ClassNode[] interfaces = classNode.getInterfaces();
        for (ClassNode anInterface : interfaces) {
            List interfacesMethods = anInterface.getMethods();
            Map genericsSpec = createGenericsSpec(anInterface, oldGenericsSpec);
            for (Object declaredMethod : declaredMethods) {
                MethodNode method = (MethodNode) declaredMethod;
                if (method.isStatic()) continue;
                storeMissingCovariantMethods(interfacesMethods,method,methodsToAdd,genericsSpec);
            }
            addCovariantMethods(anInterface, declaredMethods, abstractMethods, methodsToAdd, genericsSpec);
        }
        
    }
    
    private MethodNode getCovariantImplementation(final MethodNode oldMethod, final MethodNode overridingMethod, Map genericsSpec) {
        // method name
        if (!oldMethod.getName().equals(overridingMethod.getName())) return null;
        if ((overridingMethod.getModifiers() & ACC_BRIDGE) != 0) return null;

        // parameters
        boolean normalEqualParameters = equalParametersNormal(overridingMethod,oldMethod);
        boolean genericEqualParameters = equalParametersWithGenerics(overridingMethod,oldMethod,genericsSpec);
        if (!normalEqualParameters && !genericEqualParameters) return null;

        // return type
        ClassNode mr = overridingMethod.getReturnType();
        ClassNode omr = oldMethod.getReturnType();
        boolean equalReturnType = mr.equals(omr);

        ClassNode testmr = correctToGenericsSpec(genericsSpec,omr);
        if (!isAssignable(mr,testmr)){
            throw new RuntimeParserException(
                    "The return type of "+
                    overridingMethod.getTypeDescriptor()+
                    " in "+overridingMethod.getDeclaringClass().getName()+
                            " is incompatible with " + testmr.getName() +
                    " in "+oldMethod.getDeclaringClass().getName(),
                    overridingMethod);
        }

        if (equalReturnType && normalEqualParameters) return null;

        if ((oldMethod.getModifiers()&ACC_FINAL)!=0) {
            throw new RuntimeParserException(
                    "Cannot override final method "+
                    oldMethod.getTypeDescriptor()+
                    " in "+oldMethod.getDeclaringClass().getName(),
                    overridingMethod);
        }
        if (oldMethod.isStatic() != overridingMethod.isStatic()){
            throw new RuntimeParserException(
                    "Cannot override method "+
                    oldMethod.getTypeDescriptor()+
                    " in "+oldMethod.getDeclaringClass().getName()+
                    " with disparate static modifier",
                    overridingMethod);
        }
        if (!equalReturnType) {
            boolean oldM = ClassHelper.isPrimitiveType(oldMethod.getReturnType());
            boolean newM = ClassHelper.isPrimitiveType(overridingMethod.getReturnType());
            if (oldM || newM) {
                String message="";
                if (oldM && newM) {
                    message = " with old and new method having different primitive return types";
                } else if (newM) {
                    message = " with new method having a primitive return type and old method not";
                } else /* oldM */ {
                    message = " with old method having a primitive return type and new method not";
                }
                throw new RuntimeParserException(
                        "Cannot override method " + 
                            oldMethod.getTypeDescriptor() +
                            " in " + oldMethod.getDeclaringClass().getName() +
                            message,
                        overridingMethod);
            }
        }
        
        // if we reach this point we have at least one parameter or return type, that
        // is different in its specified form. That means we have to create a bridge method!
        MethodNode newMethod = new MethodNode(
                oldMethod.getName(),
                overridingMethod.getModifiers() | ACC_SYNTHETIC | ACC_BRIDGE,
                oldMethod.getReturnType().getPlainNodeReference(),
                cleanParameters(oldMethod.getParameters()),
                oldMethod.getExceptions(),
                null
        );
        List instructions = new ArrayList(1);
        instructions.add (
                new BytecodeInstruction() {
                    public void visit(MethodVisitor mv) {
                        mv.visitVarInsn(ALOAD,0);
                        Parameter[] para = oldMethod.getParameters();
                        Parameter[] goal = overridingMethod.getParameters();
                        int doubleSlotOffset = 0;
                        for (int i = 0; i < para.length; i++) {
                            ClassNode type = para[i].getType();
                            BytecodeHelper.load(mv, type, i+1+doubleSlotOffset);
                            if (type.redirect()==ClassHelper.double_TYPE ||
                                type.redirect()==ClassHelper.long_TYPE)
                            {
                                doubleSlotOffset++;
                            }
                            if (!type.equals(goal[i].getType())) {
                                BytecodeHelper.doCast(mv,goal[i].getType());
                            }
                        }
                        mv.visitMethodInsn(INVOKEVIRTUAL, BytecodeHelper.getClassInternalName(classNode), overridingMethod.getName(), BytecodeHelper.getMethodDescriptor(overridingMethod.getReturnType(), overridingMethod.getParameters()), false);
                        
                        BytecodeHelper.doReturn(mv, oldMethod.getReturnType());
                    }
                }

        );
        newMethod.setCode(new BytecodeSequence(instructions));
        return newMethod;
    }

   private boolean isAssignable(ClassNode node, ClassNode testNode) {
        if (node.isArray() && testNode.isArray()) {
            return isArrayAssignable(node.getComponentType(), testNode.getComponentType());
        }
        if (testNode.isInterface()) {
            if (node.equals(testNode) || node.implementsInterface(testNode)) return true;
        }
        return node.isDerivedFrom(testNode);
    }

    private boolean isArrayAssignable(ClassNode node, ClassNode testNode) {
        if (node.isArray() && testNode.isArray()) { return isArrayAssignable(node.getComponentType(), testNode.getComponentType()); }
        return node.equals(testNode);
    }

    private Parameter[] cleanParameters(Parameter[] parameters) {
        Parameter[] params = new Parameter[parameters.length];
        for (int i = 0; i < params.length; i++) {
            params[i] = new Parameter(cleanType(parameters[i].getType()), parameters[i].getName());
        }
        return params;
    }

    private static ClassNode cleanType(ClassNode type) {
        // todo: should this be directly handled by getPlainNodeReference?
        if (type.isArray()) return cleanType(type.getComponentType()).makeArray();
        return type.getPlainNodeReference();
    }

    private void storeMissingCovariantMethods(Collection methods, MethodNode method, Map methodsToAdd, Map genericsSpec) {
        for (Object method1 : methods) {
            MethodNode toOverride = (MethodNode) method1;
            MethodNode bridgeMethod = getCovariantImplementation(toOverride,method,genericsSpec);
            if (bridgeMethod==null) continue;
            methodsToAdd.put (bridgeMethod.getTypeDescriptor(),bridgeMethod);
            return;
        }
    }
    
    private boolean equalParametersNormal(MethodNode m1, MethodNode m2) {
        Parameter[] p1 = m1.getParameters();
        Parameter[] p2 = m2.getParameters();
        if (p1.length!=p2.length) return false;
        for (int i = 0; i < p2.length; i++) {
            ClassNode type = p2[i].getType();
            ClassNode parameterType = p1[i].getType();
            if (!parameterType.equals(type)) return false;
        }
        return true;
    }

    private boolean equalParametersWithGenerics(MethodNode m1, MethodNode m2, Map genericsSpec) {
        Parameter[] p1 = m1.getParameters();
        Parameter[] p2 = m2.getParameters();
        if (p1.length!=p2.length) return false;
        for (int i = 0; i < p2.length; i++) {
            ClassNode type = p2[i].getType();
            ClassNode genericsType = correctToGenericsSpec(genericsSpec,type);
            ClassNode parameterType = p1[i].getType();
            if (!parameterType.equals(genericsType)) return false;
        }
        return true;
    }
    
    private boolean moveOptimizedConstantsInitialization(final ClassNode node) {
        if (node.isInterface()) return false;

        final int mods = Opcodes.ACC_STATIC|Opcodes.ACC_SYNTHETIC| Opcodes.ACC_PUBLIC;
        String name = SWAP_INIT;
        BlockStatement methodCode = new BlockStatement();
        node.addSyntheticMethod(
                name, mods, ClassHelper.VOID_TYPE,
                Parameter.EMPTY_ARRAY, ClassNode.EMPTY_ARRAY, methodCode);        
        
        methodCode.addStatement(new SwapInitStatement());
        for (FieldNode fn : node.getFields()) {
            if (!fn.isStatic() || !fn.isSynthetic() || !fn.getName().startsWith("$const$")) continue;
            if (fn.getInitialExpression()==null) continue;
            final FieldExpression fe = new FieldExpression(fn);
            if (fn.getType().equals(ClassHelper.REFERENCE_TYPE)) fe.setUseReferenceDirectly(true);
            ConstantExpression init = (ConstantExpression) fn.getInitialExpression();
            ExpressionStatement statement =
                    new ExpressionStatement(
                            new BinaryExpression(
                                    fe,
                                    Token.newSymbol(Types.EQUAL, fn.getLineNumber(), fn.getColumnNumber()),
                                    init));
            fn.setInitialValueExpression(null);
            init.setConstantName(null);
            methodCode.addStatement(statement);
        }
        
        return true;
    }

    /**
     * When constant expressions are created, the value is always wrapped to a non primitive type.
     * Some constant expressions are optimized to return primitive types, but not all primitives are
     * handled. This method guarantees to return a similar constant expression but with a primitive type
     * instead of a boxed type.
     *
     * Additionaly, single char strings are converted to 'char' types.
     *
     * @param constantExpression a constant expression
     * @return the same instance of constant expression if the type is already primitive, or a primitive
     * constant if possible.
     */
    public static ConstantExpression transformToPrimitiveConstantIfPossible(ConstantExpression constantExpression) {
        Object value = constantExpression.getValue();
        if (value ==null) return constantExpression;
        ConstantExpression result;
        ClassNode type = constantExpression.getType();
        if (ClassHelper.isPrimitiveType(type)) return constantExpression;
        if (value instanceof String && ((String)value).length()==1) {
            result = new ConstantExpression(((String)value).charAt(0));
            result.setType(ClassHelper.char_TYPE);
        } else {
            type = ClassHelper.getUnwrapper(type);
            result = new ConstantExpression(value, true);
            result.setType(type);
        }
        return result;
    }

    private static class SwapInitStatement extends BytecodeSequence {

        private WriterController controller;

        public SwapInitStatement() {
            super(new SwapInitInstruction());
            ((SwapInitInstruction)getInstructions().get(0)).statement = this;
        }

        @Override
        public void visit(final GroovyCodeVisitor visitor) {
            if (visitor instanceof AsmClassGenerator) {
                AsmClassGenerator generator = (AsmClassGenerator) visitor;
                controller = generator.getController();
            }
            super.visit(visitor);
        }

        private static class SwapInitInstruction extends BytecodeInstruction {
            SwapInitStatement statement;

            @Override
            public void visit(final MethodVisitor mv) {
                statement.controller.getCallSiteWriter().makeCallSiteArrayInitializer();
            }
        }
    }

}




© 2015 - 2024 Weber Informatics LLC | Privacy Policy