Groovy example source code file (AbstractASTTransformUtil.java)

This example Groovy source code file (AbstractASTTransformUtil.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

arraylist, binaryexpression, booleanexpression, booleanexpression, compare_equal, compare_not_equal, emptystatement, expression, expression, ifstatement, ifstatement, list, list, statement, util

The Groovy AbstractASTTransformUtil.java source code

/*
 * Copyright 2008-2011 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.transform;

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.BooleanExpression;
import org.codehaus.groovy.ast.expr.ClassExpression;
import org.codehaus.groovy.ast.expr.ConstantExpression;
import org.codehaus.groovy.ast.expr.Expression;
import org.codehaus.groovy.ast.expr.MethodCallExpression;
import org.codehaus.groovy.ast.expr.PropertyExpression;
import org.codehaus.groovy.ast.expr.VariableExpression;
import org.codehaus.groovy.ast.stmt.EmptyStatement;
import org.codehaus.groovy.ast.stmt.ExpressionStatement;
import org.codehaus.groovy.ast.stmt.IfStatement;
import org.codehaus.groovy.ast.stmt.ReturnStatement;
import org.codehaus.groovy.ast.stmt.Statement;
import org.codehaus.groovy.classgen.Verifier;
import org.codehaus.groovy.syntax.Token;
import org.codehaus.groovy.syntax.Types;
import org.objectweb.asm.Opcodes;

import java.util.ArrayList;
import java.util.List;

public abstract class AbstractASTTransformUtil implements Opcodes {
    private static final Token COMPARE_EQUAL = Token.newSymbol(Types.COMPARE_EQUAL, -1, -1);
    private static final Token COMPARE_NOT_EQUAL = Token.newSymbol(Types.COMPARE_NOT_EQUAL, -1, -1);
    private static final Token INSTANCEOF = Token.newSymbol(Types.KEYWORD_INSTANCEOF, -1, -1);
    private static final Token ASSIGN = Token.newSymbol(Types.ASSIGN, -1, -1);

    public static boolean hasDeclaredMethod(ClassNode cNode, String name, int argsCount) {
        List<MethodNode> ms = cNode.getDeclaredMethods(name);
        for (MethodNode m : ms) {
            Parameter[] paras = m.getParameters();
            if (paras != null && paras.length == argsCount) {
                return true;
            }
        }
        return false;
    }

    public static Statement returnFalseIfWrongType(ClassNode cNode, Expression other) {
        return new IfStatement(
                notEqualClasses(cNode, other),
                new ReturnStatement(ConstantExpression.FALSE),
                new EmptyStatement()
        );
    }

    public static Statement returnFalseIfNotInstanceof(ClassNode cNode, Expression other) {
        return new IfStatement(
                isInstanceof(cNode, other),
                new EmptyStatement(),
                new ReturnStatement(ConstantExpression.FALSE)
        );
    }

    public static IfStatement returnFalseIfNull(Expression other) {
        return new IfStatement(
                equalsNullExpr(other),
                new ReturnStatement(ConstantExpression.FALSE),
                new EmptyStatement()
        );
    }

    public static IfStatement returnTrueIfIdentical(Expression self, Expression other) {
        return new IfStatement(
                identicalExpr(self, other),
                new ReturnStatement(ConstantExpression.TRUE),
                new EmptyStatement()
        );
    }

    @Deprecated
    public static Statement returnFalseIfPropertyNotEqual(FieldNode fNode, Expression other) {
        return returnFalseIfFieldNotEqual(fNode, other);
    }

    public static Statement returnFalseIfPropertyNotEqual(PropertyNode pNode, Expression other) {
        return new IfStatement(
                notEqualsPropertyExpr(pNode, other),
                new ReturnStatement(ConstantExpression.FALSE),
                new EmptyStatement()
        );
    }

    public static Statement returnFalseIfFieldNotEqual(FieldNode fNode, Expression other) {
        return new IfStatement(
                notEqualsFieldExpr(fNode, other),
                new ReturnStatement(ConstantExpression.FALSE),
                new EmptyStatement()
        );
    }

    public static List<PropertyNode> getInstanceProperties(ClassNode cNode) {
        final List<PropertyNode> result = new ArrayList();
        for (PropertyNode pNode : cNode.getProperties()) {
            if (!pNode.isStatic()) {
                result.add(pNode);
            }
        }
        return result;
    }

    public static List<FieldNode> getInstancePropertyFields(ClassNode cNode) {
        final List<FieldNode> result = new ArrayList();
        for (PropertyNode pNode : cNode.getProperties()) {
            if (!pNode.isStatic()) {
                result.add(pNode.getField());
            }
        }
        return result;
    }

    public static List<FieldNode> getInstanceNonPropertyFields(ClassNode cNode) {
        final List<FieldNode> result = new ArrayList();
        for (FieldNode fNode : cNode.getFields()) {
            if (!fNode.isStatic() && cNode.getProperty(fNode.getName()) == null) {
                result.add(fNode);
            }
        }
        return result;
    }

    public static List<FieldNode> getSuperPropertyFields(ClassNode cNode) {
        final List<FieldNode> result;
        if (cNode == ClassHelper.OBJECT_TYPE) {
            result = new ArrayList<FieldNode>();
        } else {
            result = getSuperPropertyFields(cNode.getSuperClass());
        }
        for (PropertyNode pNode : cNode.getProperties()) {
            if (!pNode.isStatic()) {
                result.add(pNode.getField());
            }
        }
        return result;
    }

    public static List<FieldNode> getSuperNonPropertyFields(ClassNode cNode) {
        final List<FieldNode> result;
        if (cNode == ClassHelper.OBJECT_TYPE) {
            result = new ArrayList<FieldNode>();
        } else {
            result = getSuperNonPropertyFields(cNode.getSuperClass());
        }
        for (FieldNode fNode : cNode.getFields()) {
            if (!fNode.isStatic() && cNode.getProperty(fNode.getName()) == null) {
                result.add(fNode);
            }
        }
        return result;
    }

    public static Statement assignStatement(Expression fieldExpr, Expression value) {
        return new ExpressionStatement(assignExpr(fieldExpr, value));
    }

    private static Expression assignExpr(Expression expression, Expression value) {
        return new BinaryExpression(expression, ASSIGN, value);
    }

    public static BooleanExpression isInstanceOf(Expression objectExpression, ClassNode cNode) {
        return new BooleanExpression(new BinaryExpression(objectExpression, INSTANCEOF, new ClassExpression(cNode)));
    }

    public static BooleanExpression equalsNullExpr(Expression argExpr) {
        return new BooleanExpression(new BinaryExpression(argExpr, COMPARE_EQUAL, ConstantExpression.NULL));
    }

    public static BooleanExpression isZeroExpr(Expression expr) {
        return new BooleanExpression(new BinaryExpression(expr, COMPARE_EQUAL, new ConstantExpression(0)));
    }

    private static BooleanExpression notEqualsFieldExpr(FieldNode fNode, Expression other) {
        final Expression fieldExpr = new VariableExpression(fNode);
        final Expression otherExpr = new PropertyExpression(other, fNode.getName());
        return new BooleanExpression(new BinaryExpression(fieldExpr, COMPARE_NOT_EQUAL, otherExpr));
    }

    private static BooleanExpression notEqualsPropertyExpr(PropertyNode pNode, Expression other) {
        String getterName = "get" + Verifier.capitalize(pNode.getName());
        Expression selfGetter = new MethodCallExpression(VariableExpression.THIS_EXPRESSION, getterName, MethodCallExpression.NO_ARGUMENTS);
        Expression otherGetter = new MethodCallExpression(other, getterName, MethodCallExpression.NO_ARGUMENTS);
        return new BooleanExpression(new BinaryExpression(selfGetter, COMPARE_NOT_EQUAL, otherGetter));
    }

    private static BooleanExpression identicalExpr(Expression self, Expression other) {
        return new BooleanExpression(new MethodCallExpression(self, "is", new ArgumentListExpression(other)));
    }

    private static BooleanExpression notEqualClasses(ClassNode cNode, Expression other) {
        return new BooleanExpression(new BinaryExpression(new ClassExpression(cNode), COMPARE_NOT_EQUAL,
                new MethodCallExpression(other, "getClass", MethodCallExpression.NO_ARGUMENTS)));
    }

    public static BooleanExpression isInstanceof(ClassNode cNode, Expression other) {
        return new BooleanExpression(new BinaryExpression(other, INSTANCEOF, new ClassExpression(cNode)));
    }

    public static boolean isOrImplements(ClassNode fieldType, ClassNode interfaceType) {
        return fieldType.equals(interfaceType) || fieldType.implementsInterface(interfaceType);
    }

    public static BooleanExpression isTrueExpr(Expression argExpr) {
        return new BooleanExpression(new BinaryExpression(argExpr, COMPARE_EQUAL, ConstantExpression.TRUE));
    }

    public static BooleanExpression isOneExpr(Expression expr) {
        return new BooleanExpression(new BinaryExpression(expr, COMPARE_EQUAL, new ConstantExpression(1)));
    }

    public static Statement safeExpression(Expression fieldExpr, Expression expression) {
        return new IfStatement(
                equalsNullExpr(fieldExpr),
                new ExpressionStatement(fieldExpr),
                new ExpressionStatement(expression));
    }

    public static Statement createConstructorStatementDefault(FieldNode fNode) {
        final String name = fNode.getName();
        final Expression fieldExpr = new PropertyExpression(VariableExpression.THIS_EXPRESSION, name);
        Expression initExpr = fNode.getInitialValueExpression();
        if (initExpr == null) initExpr = ConstantExpression.NULL;
        Expression value = findArg(name);
        return new IfStatement(
                equalsNullExpr(value),
                new IfStatement(
                        equalsNullExpr(initExpr),
                        new EmptyStatement(),
                        assignStatement(fieldExpr, initExpr)),
                assignStatement(fieldExpr, value));
    }

    public static Expression findArg(String argName) {
        return new PropertyExpression(new VariableExpression("args"), argName);
    }

}