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Spice up your java: Automatic Resource Management, automatic generation of getters, setters, equals, hashCode and toString, and more!
/*
* Copyright (C) 2015 The Project Lombok Authors.
*
* 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.eclipse.handlers;
import static lombok.core.handlers.HandlerUtil.*;
import static lombok.eclipse.Eclipse.*;
import static lombok.eclipse.handlers.EclipseHandlerUtil.*;
import java.util.Arrays;
import org.eclipse.jdt.internal.compiler.ast.ASTNode;
import org.eclipse.jdt.internal.compiler.ast.AbstractMethodDeclaration;
import org.eclipse.jdt.internal.compiler.ast.AllocationExpression;
import org.eclipse.jdt.internal.compiler.ast.Annotation;
import org.eclipse.jdt.internal.compiler.ast.Clinit;
import org.eclipse.jdt.internal.compiler.ast.CompilationUnitDeclaration;
import org.eclipse.jdt.internal.compiler.ast.ConstructorDeclaration;
import org.eclipse.jdt.internal.compiler.ast.ExplicitConstructorCall;
import org.eclipse.jdt.internal.compiler.ast.Expression;
import org.eclipse.jdt.internal.compiler.ast.FieldDeclaration;
import org.eclipse.jdt.internal.compiler.ast.MethodDeclaration;
import org.eclipse.jdt.internal.compiler.ast.QualifiedTypeReference;
import org.eclipse.jdt.internal.compiler.ast.Statement;
import org.eclipse.jdt.internal.compiler.ast.StringLiteral;
import org.eclipse.jdt.internal.compiler.ast.ThrowStatement;
import org.eclipse.jdt.internal.compiler.ast.TypeDeclaration;
import org.eclipse.jdt.internal.compiler.classfmt.ClassFileConstants;
import org.eclipse.jdt.internal.compiler.lookup.TypeConstants;
import org.mangosdk.spi.ProviderFor;
import lombok.ConfigurationKeys;
import lombok.core.AnnotationValues;
import lombok.core.HandlerPriority;
import lombok.core.AST.Kind;
import lombok.eclipse.EclipseAnnotationHandler;
import lombok.eclipse.EclipseNode;
import lombok.experimental.UtilityClass;
/**
* Handles the {@code lombok.experimental.UtilityClass} annotation for eclipse.
*/
@HandlerPriority(-4096) //-2^12; to ensure @FieldDefaults picks up on the 'static' we set here.
@ProviderFor(EclipseAnnotationHandler.class)
public class HandleUtilityClass extends EclipseAnnotationHandler {
@Override public void handle(AnnotationValues annotation, Annotation ast, EclipseNode annotationNode) {
handleFlagUsage(annotationNode, ConfigurationKeys.UTILITY_CLASS_FLAG_USAGE, "@UtilityClass");
EclipseNode typeNode = annotationNode.up();
if (!checkLegality(typeNode, annotationNode)) return;
changeModifiersAndGenerateConstructor(annotationNode.up(), annotationNode);
}
private static boolean checkLegality(EclipseNode typeNode, EclipseNode errorNode) {
TypeDeclaration typeDecl = null;
if (typeNode.get() instanceof TypeDeclaration) typeDecl = (TypeDeclaration) typeNode.get();
int modifiers = typeDecl == null ? 0 : typeDecl.modifiers;
boolean notAClass = (modifiers & (ClassFileConstants.AccInterface | ClassFileConstants.AccAnnotation | ClassFileConstants.AccEnum)) != 0;
if (typeDecl == null || notAClass) {
errorNode.addError("@UtilityClass is only supported on a class (can't be an interface, enum, or annotation).");
return false;
}
// It might be an inner class. This is okay, but only if it is / can be a static inner class. Thus, all of its parents have to be static inner classes until the top-level.
EclipseNode typeWalk = typeNode;
while (true) {
typeWalk = typeWalk.up();
switch (typeWalk.getKind()) {
case TYPE:
if ((((TypeDeclaration) typeWalk.get()).modifiers & (ClassFileConstants.AccStatic | ClassFileConstants.AccInterface | ClassFileConstants.AccAnnotation | ClassFileConstants.AccEnum)) != 0) continue;
if (typeWalk.up().getKind() == Kind.COMPILATION_UNIT) return true;
errorNode.addError("@UtilityClass automatically makes the class static, however, this class cannot be made static.");
return false;
case COMPILATION_UNIT:
return true;
default:
errorNode.addError("@UtilityClass cannot be placed on a method local or anonymous inner class, or any class nested in such a class.");
return false;
}
}
}
private void changeModifiersAndGenerateConstructor(EclipseNode typeNode, EclipseNode annotationNode) {
TypeDeclaration classDecl = (TypeDeclaration) typeNode.get();
boolean makeConstructor = true;
classDecl.modifiers |= ClassFileConstants.AccFinal;
boolean markStatic = true;
boolean requiresClInit = false;
boolean alreadyHasClinit = false;
if (typeNode.up().getKind() == Kind.COMPILATION_UNIT) markStatic = false;
if (markStatic && typeNode.up().getKind() == Kind.TYPE) {
TypeDeclaration typeDecl = (TypeDeclaration) typeNode.up().get();
if ((typeDecl.modifiers & ClassFileConstants.AccInterface) != 0) markStatic = false;
}
if (markStatic) classDecl.modifiers |= ClassFileConstants.AccStatic;
for (EclipseNode element : typeNode.down()) {
if (element.getKind() == Kind.FIELD) {
FieldDeclaration fieldDecl = (FieldDeclaration) element.get();
if ((fieldDecl.modifiers & ClassFileConstants.AccStatic) == 0) {
requiresClInit = true;
fieldDecl.modifiers |= ClassFileConstants.AccStatic;
}
} else if (element.getKind() == Kind.METHOD) {
AbstractMethodDeclaration amd = (AbstractMethodDeclaration) element.get();
if (amd instanceof ConstructorDeclaration) {
ConstructorDeclaration constrDecl = (ConstructorDeclaration) element.get();
if (getGeneratedBy(constrDecl) == null && (constrDecl.bits & ASTNode.IsDefaultConstructor) == 0) {
element.addError("@UtilityClasses cannot have declared constructors.");
makeConstructor = false;
continue;
}
} else if (amd instanceof MethodDeclaration) {
amd.modifiers |= ClassFileConstants.AccStatic;
} else if (amd instanceof Clinit) {
alreadyHasClinit = true;
}
} else if (element.getKind() == Kind.TYPE) {
((TypeDeclaration) element.get()).modifiers |= ClassFileConstants.AccStatic;
}
}
if (makeConstructor) createPrivateDefaultConstructor(typeNode, annotationNode);
if (requiresClInit && !alreadyHasClinit) classDecl.addClinit();
}
private static final char[][] JAVA_LANG_UNSUPPORTED_OPERATION_EXCEPTION = new char[][] {
TypeConstants.JAVA, TypeConstants.LANG, "UnsupportedOperationException".toCharArray()
};
private static final char[] UNSUPPORTED_MESSAGE = "This is a utility class and cannot be instantiated".toCharArray();
private void createPrivateDefaultConstructor(EclipseNode typeNode, EclipseNode sourceNode) {
ASTNode source = sourceNode.get();
TypeDeclaration typeDeclaration = ((TypeDeclaration) typeNode.get());
long p = (long) source.sourceStart << 32 | source.sourceEnd;
ConstructorDeclaration constructor = new ConstructorDeclaration(((CompilationUnitDeclaration) typeNode.top().get()).compilationResult);
constructor.modifiers = ClassFileConstants.AccPrivate;
constructor.selector = typeDeclaration.name;
constructor.constructorCall = new ExplicitConstructorCall(ExplicitConstructorCall.ImplicitSuper);
constructor.constructorCall.sourceStart = source.sourceStart;
constructor.constructorCall.sourceEnd = source.sourceEnd;
constructor.thrownExceptions = null;
constructor.typeParameters = null;
constructor.bits |= ECLIPSE_DO_NOT_TOUCH_FLAG;
constructor.bodyStart = constructor.declarationSourceStart = constructor.sourceStart = source.sourceStart;
constructor.bodyEnd = constructor.declarationSourceEnd = constructor.sourceEnd = source.sourceEnd;
constructor.arguments = null;
AllocationExpression exception = new AllocationExpression();
setGeneratedBy(exception, source);
long[] ps = new long[JAVA_LANG_UNSUPPORTED_OPERATION_EXCEPTION.length];
Arrays.fill(ps, p);
exception.type = new QualifiedTypeReference(JAVA_LANG_UNSUPPORTED_OPERATION_EXCEPTION, ps);
setGeneratedBy(exception.type, source);
exception.arguments = new Expression[] {
new StringLiteral(UNSUPPORTED_MESSAGE, source.sourceStart, source.sourceEnd, 0)
};
setGeneratedBy(exception.arguments[0], source);
ThrowStatement throwStatement = new ThrowStatement(exception, source.sourceStart, source.sourceEnd);
setGeneratedBy(throwStatement, source);
constructor.statements = new Statement[] {throwStatement};
injectMethod(typeNode, constructor);
}
}