/*
* Copyright 2008-2010 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 groovy.transform.ToString;
import org.codehaus.groovy.ast.ASTNode;
import org.codehaus.groovy.ast.AnnotatedNode;
import org.codehaus.groovy.ast.AnnotationNode;
import org.codehaus.groovy.ast.ClassHelper;
import org.codehaus.groovy.ast.ClassNode;
import org.codehaus.groovy.ast.FieldNode;
import org.codehaus.groovy.ast.MethodNode;
import org.codehaus.groovy.ast.Parameter;
import org.codehaus.groovy.ast.expr.BooleanExpression;
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.MethodCallExpression;
import org.codehaus.groovy.ast.expr.StaticMethodCallExpression;
import org.codehaus.groovy.ast.expr.VariableExpression;
import org.codehaus.groovy.ast.stmt.BlockStatement;
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.control.CompilePhase;
import org.codehaus.groovy.control.SourceUnit;
import org.codehaus.groovy.runtime.InvokerHelper;
import org.codehaus.groovy.syntax.Token;
import org.codehaus.groovy.syntax.Types;
import java.util.List;
import static org.codehaus.groovy.transform.AbstractASTTransformUtil.getInstanceNonPropertyFields;
import static org.codehaus.groovy.transform.AbstractASTTransformUtil.getInstancePropertyFields;
import static org.codehaus.groovy.transform.AbstractASTTransformUtil.hasDeclaredMethod;
/**
* Handles generation of code for the @ToString annotation.
*
* @author Paul King
*/
@GroovyASTTransformation(phase = CompilePhase.CANONICALIZATION)
public class ToStringASTTransformation extends AbstractASTTransformation {
static final Class MY_CLASS = ToString.class;
static final ClassNode MY_TYPE = new ClassNode(MY_CLASS);
static final String MY_TYPE_NAME = "@" + MY_TYPE.getNameWithoutPackage();
private static final ClassNode STRINGBUFFER_TYPE = new ClassNode(StringBuffer.class);
private static final ClassNode INVOKER_TYPE = new ClassNode(InvokerHelper.class);
private static final Token ASSIGN = Token.newSymbol(Types.ASSIGN, -1, -1);
public void visit(ASTNode[] nodes, SourceUnit source) {
init(nodes, source);
AnnotatedNode parent = (AnnotatedNode) nodes[1];
AnnotationNode anno = (AnnotationNode) nodes[0];
if (!MY_TYPE.equals(anno.getClassNode())) return;
if (parent instanceof ClassNode) {
ClassNode cNode = (ClassNode) parent;
checkNotInterface(cNode, MY_TYPE_NAME);
boolean includeSuper = memberHasValue(anno, "includeSuper", true);
if (includeSuper && cNode.getSuperClass().getName().equals("java.lang.Object")) {
addError("Error during " + MY_TYPE_NAME + " processing: includeSuper=true but '" + cNode.getName() + "' has no super class.", anno);
}
boolean includeNames = memberHasValue(anno, "includeNames", true);
boolean includeFields = memberHasValue(anno, "includeFields", true);
List<String> excludes = tokenize((String) getMemberValue(anno, "excludes"));
toStringInit(cNode, new ConstantExpression(includeNames));
createToString(cNode, includeSuper, includeFields, excludes);
}
}
public static void createToString(ClassNode cNode, boolean includeSuper, boolean includeFields, List<String> excludes) {
// make a public method if none exists otherwise try a private method with leading underscore
boolean hasExistingToString = hasDeclaredMethod(cNode, "toString", 0);
if (hasExistingToString && hasDeclaredMethod(cNode, "_toString", 0)) return;
final BlockStatement body = new BlockStatement();
// def _result = new StringBuffer()
final Expression result = new VariableExpression("_result");
final Expression init = new ConstructorCallExpression(STRINGBUFFER_TYPE, MethodCallExpression.NO_ARGUMENTS);
body.addStatement(new ExpressionStatement(new DeclarationExpression(result, ASSIGN, init)));
body.addStatement(append(result, new ConstantExpression(cNode.getName())));
body.addStatement(append(result, new ConstantExpression("(")));
boolean first = true;
List<FieldNode> list = getInstancePropertyFields(cNode);
if (includeFields) {
list.addAll(getInstanceNonPropertyFields(cNode));
}
for (FieldNode fNode : list) {
if (excludes.contains(fNode.getName()) || fNode.getName().contains("$")) continue;
first = appendPrefix(cNode, body, result, first, fNode.getName());
body.addStatement(append(result, new StaticMethodCallExpression(INVOKER_TYPE, "toString", new VariableExpression(fNode))));
}
if (includeSuper) {
appendPrefix(cNode, body, result, first, "super");
// not through MOP to avoid infinite recursion
body.addStatement(append(result, new MethodCallExpression(VariableExpression.SUPER_EXPRESSION, "toString", MethodCallExpression.NO_ARGUMENTS)));
}
body.addStatement(append(result, new ConstantExpression(")")));
body.addStatement(new ReturnStatement(new MethodCallExpression(result, "toString", MethodCallExpression.NO_ARGUMENTS)));
cNode.addMethod(new MethodNode(hasExistingToString ? "_toString" : "toString", hasExistingToString ? ACC_PRIVATE : ACC_PUBLIC,
ClassHelper.STRING_TYPE, Parameter.EMPTY_ARRAY, ClassNode.EMPTY_ARRAY, body));
}
private static boolean appendPrefix(ClassNode cNode, BlockStatement body, Expression result, boolean first, String name) {
if (first) {
first = false;
} else {
body.addStatement(append(result, new ConstantExpression(", ")));
}
body.addStatement(new IfStatement(
new BooleanExpression(new VariableExpression(cNode.getField("$print$names"))),
toStringPropertyName(result, name),
new EmptyStatement()
));
return first;
}
private static Statement toStringPropertyName(Expression result, String fName) {
final BlockStatement body = new BlockStatement();
body.addStatement(append(result, new ConstantExpression(fName)));
body.addStatement(append(result, new ConstantExpression(":")));
return body;
}
private static ExpressionStatement append(Expression result, Expression expr) {
return new ExpressionStatement(new MethodCallExpression(result, "append", expr));
}
public static void toStringInit(ClassNode cNode, ConstantExpression fieldValue) {
cNode.addField("$print$names", ACC_PRIVATE | ACC_SYNTHETIC, ClassHelper.boolean_TYPE, fieldValue);
}
}