/*
* Copyright © 2011-2012 Philipp Eichhorn
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package lombok.javac.handlers;
import static lombok.javac.handlers.JavacHandlerUtil.deleteAnnotationIfNeccessary;
import static lombok.javac.handlers.ast.JavacResolver.CLASS;
import java.util.ArrayList;
import java.util.List;
import org.mangosdk.spi.ProviderFor;
import lombok.Action;
import lombok.Function;
import lombok.Predicate;
import lombok.core.AnnotationValues;
import lombok.core.handlers.ActionFunctionAndPredicateHandler;
import lombok.core.handlers.ActionFunctionAndPredicateHandler.TemplateData;
import lombok.core.util.As;
import lombok.javac.JavacAnnotationHandler;
import lombok.javac.JavacNode;
import lombok.javac.ResolutionBased;
import lombok.javac.handlers.ast.JavacMethod;
import lombok.javac.handlers.ast.JavacType;
import com.sun.tools.javac.code.Attribute;
import com.sun.tools.javac.code.Flags;
import com.sun.tools.javac.code.Symbol;
import com.sun.tools.javac.code.Type;
import com.sun.tools.javac.code.Symbol.MethodSymbol;
import com.sun.tools.javac.code.Symbol.TypeSymbol;
import com.sun.tools.javac.tree.JCTree;
import com.sun.tools.javac.tree.JCTree.JCAnnotation;
import com.sun.tools.javac.tree.JCTree.JCExpression;
import com.sun.tools.javac.tree.JCTree.JCFieldAccess;
import com.sun.tools.javac.tree.JCTree.JCMethodDecl;
import com.sun.tools.javac.tree.JCTree.JCVariableDecl;
public class HandleActionFunctionAndPredicate {
/**
* Handles the {@link Action} annotation for javac.
*/
@ProviderFor(JavacAnnotationHandler.class)
@ResolutionBased
public static class HandleAction extends JavacAnnotationHandler<Action> {
@Override
public void handle(final AnnotationValues<Action> annotation, final JCAnnotation source, final JavacNode annotationNode) {
deleteAnnotationIfNeccessary(annotationNode, Action.class);
new HandleActionFunctionAndPredicate().handle(annotation, source, annotationNode, "void");
}
}
/**
* Handles the {@link Function} annotation for javac.
*/
@ProviderFor(JavacAnnotationHandler.class)
@ResolutionBased
public static class HandleFunction extends JavacAnnotationHandler<Function> {
@Override
public void handle(final AnnotationValues<Function> annotation, final JCAnnotation source, final JavacNode annotationNode) {
deleteAnnotationIfNeccessary(annotationNode, Function.class);
new HandleActionFunctionAndPredicate().handle(annotation, source, annotationNode, null);
}
}
/**
* Handles the {@link Predicate} annotation for javac.
*/
@ProviderFor(JavacAnnotationHandler.class)
@ResolutionBased
public static class HandlePredicate extends JavacAnnotationHandler<Predicate> {
@Override
public void handle(final AnnotationValues<Predicate> annotation, final JCAnnotation source, final JavacNode annotationNode) {
deleteAnnotationIfNeccessary(annotationNode, Predicate.class);
new HandleActionFunctionAndPredicate().handle(annotation, source, annotationNode, "boolean");
}
}
public void handle(final AnnotationValues<? extends java.lang.annotation.Annotation> annotation, final JCAnnotation source, final JavacNode annotationNode, final String forcedReturnType) {
final JCTree annotationType = source.annotationType;
final JavacMethod method = JavacMethod.methodOf(annotationNode, source);
if (method.isAbstract()) {
annotationNode.addError(String.format("@%s can be used on concrete methods only", annotationType));
return;
}
if ((forcedReturnType != null) && !method.returns(forcedReturnType)) {
annotationNode.addError(String.format("@%s can only be used on methods with '%s' as return type", annotationType, forcedReturnType));
return;
}
final Object templates = annotation.getActualExpression("value");
final TypeSymbol resolvedTemplates = resolveTemplates(method.node(), source, templates);
if (resolvedTemplates == null) {
annotationNode.addError(String.format("@%s unable to resolve template type", annotationType));
return;
}
final List<TemplateData> matchingTemplates = findTemplatesFor(method.get(), resolvedTemplates, forcedReturnType);
if (matchingTemplates.isEmpty()) {
annotationNode.addError(String.format("@%s no template found that matches the given method signature", annotationType));
return;
}
if (matchingTemplates.size() > 1) {
annotationNode.addError(String.format("@%s more than one template found that matches the given method signature", annotationType));
return;
}
// call HandleVal explicitly to ensure val gets handled before yield gets handled.
// TODO maybe we should prioritize lombok handler
method.node().traverse(new HandleVal());
new ActionFunctionAndPredicateHandler<JavacType, JavacMethod>().rebuildMethod(method, matchingTemplates.get(0), new JavacParameterValidator(), new JavacParameterSanitizer());
}
private TypeSymbol resolveTemplates(final JavacNode node, final JCAnnotation annotation, final Object templatesDef) {
if (templatesDef instanceof JCFieldAccess) {
final JCFieldAccess templates = (JCFieldAccess) templatesDef;
if (!"class".equals(As.string(templates.name))) return null;
final Type templatesType = CLASS.resolveMember(node, templates.selected);
return (templatesType == null) ? null : templatesType.asElement();
} else {
final Type annotationType = CLASS.resolveMember(node, (JCExpression) annotation.annotationType);
if (annotationType == null) return null;
final List<MethodSymbol> enclosedMethods = enclosedMethodsOf(annotationType.asElement());
if (enclosedMethods.size() != 1) return null;
final Attribute.Class defaultValue = (Attribute.Class) enclosedMethods.get(0).getDefaultValue();
return defaultValue.getValue().asElement();
}
}
private List<TemplateData> findTemplatesFor(final JCMethodDecl methodDecl, final TypeSymbol template, final String forcedReturnType) {
final List<TemplateData> foundTemplates = new ArrayList<TemplateData>();
final TemplateData templateData = templateDataFor(methodDecl, template, forcedReturnType);
if (templateData != null) foundTemplates.add(templateData);
for (Symbol enclosedElement : template.getEnclosedElements()) {
if (!(enclosedElement instanceof TypeSymbol)) continue;
final TypeSymbol enclosedType = (TypeSymbol) enclosedElement;
if (!enclosedType.isInterface() && !enclosedType.isStatic()) continue;
foundTemplates.addAll(findTemplatesFor(methodDecl, enclosedType, forcedReturnType));
}
return foundTemplates;
}
private TemplateData templateDataFor(final JCMethodDecl methodDecl, final TypeSymbol template, final String forcedReturnType) {
if ((template.flags() & (Flags.PUBLIC)) == 0) return null;
if (!template.isInterface() && ((template.flags() & (Flags.ABSTRACT)) == 0)) return null;
final List<Type> templateTypeArguments = new ArrayList<Type>(template.type.getTypeArguments());
final List<MethodSymbol> enclosedMethods = enclosedMethodsOf(template);
if (enclosedMethods.size() != 1) return null;
final MethodSymbol enclosedMethod = enclosedMethods.get(0);
final Type enclosedMethodType = enclosedMethod.type;
if (!matchesReturnType(enclosedMethodType, forcedReturnType)) return null;
final List<Type> methodTypeArguments = new ArrayList<Type>(enclosedMethodType.getParameterTypes());
if (forcedReturnType == null) methodTypeArguments.add(enclosedMethodType.getReturnType());
if (!templateTypeArguments.equals(methodTypeArguments)) return null;
if (forcedReturnType == null) {
if ((numberOfParameters(methodDecl) + 1) != templateTypeArguments.size()) return null;
} else {
if (numberOfParameters(methodDecl) != templateTypeArguments.size()) return null;
}
return new TemplateData(As.string(template.getQualifiedName()), As.string(enclosedMethod.name), forcedReturnType);
}
// for now only works for primitive return types
private boolean matchesReturnType(final Type methodType, final String forcedReturnType) {
if (forcedReturnType == null) return true;
return forcedReturnType.equals(methodType.getReturnType().toString());
}
private int numberOfParameters(final JCMethodDecl methodDecl) {
int numberOfParameters = 0;
for (JCVariableDecl param : methodDecl.params) {
if (!As.string(param.name).startsWith("_")) numberOfParameters++;
}
return numberOfParameters;
}
private List<MethodSymbol> enclosedMethodsOf(final TypeSymbol type) {
final List<MethodSymbol> enclosedMethods = new ArrayList<MethodSymbol>();
for (Symbol enclosedElement : type.getEnclosedElements()) {
if (enclosedElement instanceof MethodSymbol) {
if ((enclosedElement.flags() & (Flags.ABSTRACT)) == 0) continue;
enclosedMethods.add((MethodSymbol) enclosedElement);
}
}
return enclosedMethods;
}
}