dagger.internal.codegen.langmodel.DaggerElements Maven / Gradle / Ivy
/*
* Copyright (C) 2013 The Dagger 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 dagger.internal.codegen.langmodel;
import static com.google.auto.common.MoreElements.asExecutable;
import static com.google.auto.common.MoreElements.hasModifiers;
import static com.google.common.base.Preconditions.checkNotNull;
import static com.google.common.collect.Lists.asList;
import static java.util.Comparator.comparing;
import static java.util.stream.Collectors.toSet;
import static javax.lang.model.element.Modifier.ABSTRACT;
import com.google.auto.common.MoreElements;
import com.google.auto.common.MoreTypes;
import com.google.common.collect.FluentIterable;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.ImmutableSet;
import com.google.common.collect.Iterables;
import com.google.common.graph.Traverser;
import com.squareup.javapoet.ClassName;
import dagger.Reusable;
import dagger.internal.codegen.base.ClearableCache;
import java.io.Writer;
import java.util.Collection;
import java.util.Comparator;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Optional;
import java.util.Set;
import java.util.function.Predicate;
import java.util.stream.Collectors;
import javax.annotation.processing.ProcessingEnvironment;
import javax.lang.model.element.AnnotationMirror;
import javax.lang.model.element.AnnotationValue;
import javax.lang.model.element.Element;
import javax.lang.model.element.ElementKind;
import javax.lang.model.element.ElementVisitor;
import javax.lang.model.element.ExecutableElement;
import javax.lang.model.element.Name;
import javax.lang.model.element.PackageElement;
import javax.lang.model.element.QualifiedNameable;
import javax.lang.model.element.TypeElement;
import javax.lang.model.element.VariableElement;
import javax.lang.model.type.ArrayType;
import javax.lang.model.type.DeclaredType;
import javax.lang.model.type.ErrorType;
import javax.lang.model.type.ExecutableType;
import javax.lang.model.type.IntersectionType;
import javax.lang.model.type.NoType;
import javax.lang.model.type.NullType;
import javax.lang.model.type.PrimitiveType;
import javax.lang.model.type.TypeMirror;
import javax.lang.model.type.TypeVariable;
import javax.lang.model.type.UnionType;
import javax.lang.model.type.WildcardType;
import javax.lang.model.util.AbstractTypeVisitor8;
import javax.lang.model.util.Elements;
import javax.lang.model.util.SimpleElementVisitor8;
import javax.lang.model.util.Types;
/** Extension of {@link Elements} that adds Dagger-specific methods. */
@Reusable
public final class DaggerElements implements Elements, ClearableCache {
private final Map> getLocalAndInheritedMethodsCache =
new HashMap<>();
private final Elements elements;
private final Types types;
public DaggerElements(Elements elements, Types types) {
this.elements = checkNotNull(elements);
this.types = checkNotNull(types);
}
public DaggerElements(ProcessingEnvironment processingEnv) {
this(processingEnv.getElementUtils(), processingEnv.getTypeUtils());
}
/**
* Returns {@code true} if {@code encloser} is equal to {@code enclosed} or recursively encloses
* it.
*/
public static boolean elementEncloses(TypeElement encloser, Element enclosed) {
return Iterables.contains(GET_ENCLOSED_ELEMENTS.breadthFirst(encloser), enclosed);
}
private static final Traverser GET_ENCLOSED_ELEMENTS =
Traverser.forTree(Element::getEnclosedElements);
public ImmutableSet getLocalAndInheritedMethods(TypeElement type) {
return getLocalAndInheritedMethodsCache.computeIfAbsent(
type, k -> MoreElements.getLocalAndInheritedMethods(type, types, elements));
}
public ImmutableSet getUnimplementedMethods(TypeElement type) {
return FluentIterable.from(getLocalAndInheritedMethods(type))
.filter(hasModifiers(ABSTRACT))
.toSet();
}
/** Returns the type element for a class. */
public TypeElement getTypeElement(Class clazz) {
return getTypeElement(clazz.getCanonicalName());
}
@Override
public TypeElement getTypeElement(CharSequence name) {
return elements.getTypeElement(name);
}
/** Returns the type element for a class name. */
public TypeElement getTypeElement(ClassName className) {
return getTypeElement(className.canonicalName());
}
/** Returns the argument or the closest enclosing element that is a {@link TypeElement}. */
public static TypeElement closestEnclosingTypeElement(Element element) {
return element.accept(CLOSEST_ENCLOSING_TYPE_ELEMENT, null);
}
private static final ElementVisitor CLOSEST_ENCLOSING_TYPE_ELEMENT =
new SimpleElementVisitor8() {
@Override
protected TypeElement defaultAction(Element element, Void p) {
return element.getEnclosingElement().accept(this, null);
}
@Override
public TypeElement visitType(TypeElement type, Void p) {
return type;
}
};
/**
* Compares elements according to their declaration order among siblings. Only valid to compare
* elements enclosed by the same parent.
*/
public static final Comparator DECLARATION_ORDER =
comparing(element -> siblings(element).indexOf(element));
// For parameter elements, element.getEnclosingElement().getEnclosedElements() is empty. So
// instead look at the parameter list of the enclosing executable.
private static List siblings(Element element) {
return element.getKind().equals(ElementKind.PARAMETER)
? asExecutable(element.getEnclosingElement()).getParameters()
: element.getEnclosingElement().getEnclosedElements();
}
/**
* Returns {@code true} iff the given element has an {@link AnnotationMirror} whose {@linkplain
* AnnotationMirror#getAnnotationType() annotation type} has the same canonical name as any of
* that of {@code annotationClasses}.
*/
public static boolean isAnyAnnotationPresent(
Element element, Iterable annotationClasses) {
for (ClassName annotation : annotationClasses) {
if (isAnnotationPresent(element, annotation)) {
return true;
}
}
return false;
}
@SafeVarargs
public static boolean isAnyAnnotationPresent(
Element element, ClassName first, ClassName... otherAnnotations) {
return isAnyAnnotationPresent(element, asList(first, otherAnnotations));
}
/**
* Returns {@code true} iff the given element has an {@link AnnotationMirror} whose {@linkplain
* AnnotationMirror#getAnnotationType() annotation type} is equivalent to {@code annotationType}.
*/
public static boolean isAnnotationPresent(Element element, TypeMirror annotationType) {
return element.getAnnotationMirrors().stream()
.map(AnnotationMirror::getAnnotationType)
.anyMatch(candidate -> MoreTypes.equivalence().equivalent(candidate, annotationType));
}
/**
* Returns {@code true} iff the given element has an {@link AnnotationMirror} whose {@link
* AnnotationMirror#getAnnotationType() annotation type} has the same canonical name as that of
* {@code annotationClass}. This method is a safer alternative to calling {@link
* Element#getAnnotation} and checking for {@code null} as it avoids any interaction with
* annotation proxies.
*/
public static boolean isAnnotationPresent(Element element, ClassName annotationName) {
return getAnnotationMirror(element, annotationName).isPresent();
}
/**
* Returns the annotation present on {@code element} whose type is {@code first} or within {@code
* rest}, checking each annotation type in order.
*/
@SafeVarargs
public static Optional getAnyAnnotation(
Element element, ClassName first, ClassName... rest) {
return getAnyAnnotation(element, asList(first, rest));
}
/**
* Returns the annotation present on {@code element} whose type is in {@code annotations},
* checking each annotation type in order.
*/
public static Optional getAnyAnnotation(
Element element, Collection annotations) {
return element.getAnnotationMirrors().stream()
.filter(hasAnnotationTypeIn(annotations))
.map((AnnotationMirror a) -> a) // Avoid returning Optional.
.findFirst();
}
/** Returns the annotations present on {@code element} of all types. */
@SafeVarargs
public static ImmutableSet getAllAnnotations(
Element element, ClassName first, ClassName... rest) {
return ImmutableSet.copyOf(
Iterables.filter(
element.getAnnotationMirrors(), hasAnnotationTypeIn(asList(first, rest))::test));
}
// Note: This is similar to auto-common's MoreElements except using ClassName rather than Class.
// TODO(bcorso): Contribute a String version to auto-common's MoreElements?
/**
* Returns an {@link AnnotationMirror} for the annotation of type {@code annotationClass} on
* {@code element}, or {@link Optional#empty()} if no such annotation exists. This method is a
* safer alternative to calling {@link Element#getAnnotation} as it avoids any interaction with
* annotation proxies.
*/
public static Optional getAnnotationMirror(
Element element, ClassName annotationName) {
String annotationClassName = annotationName.canonicalName();
for (AnnotationMirror annotationMirror : element.getAnnotationMirrors()) {
TypeElement annotationTypeElement =
MoreElements.asType(annotationMirror.getAnnotationType().asElement());
if (annotationTypeElement.getQualifiedName().contentEquals(annotationClassName)) {
return Optional.of(annotationMirror);
}
}
return Optional.empty();
}
private static Predicate hasAnnotationTypeIn(
Collection annotations) {
Set annotationClassNames =
annotations.stream().map(ClassName::canonicalName).collect(toSet());
return annotation ->
annotationClassNames.contains(
MoreTypes.asTypeElement(annotation.getAnnotationType()).getQualifiedName().toString());
}
public static ImmutableSet suppressedWarnings(Element element) {
SuppressWarnings suppressedWarnings = element.getAnnotation(SuppressWarnings.class);
if (suppressedWarnings == null) {
return ImmutableSet.of();
}
return ImmutableSet.copyOf(suppressedWarnings.value());
}
/**
* Returns the field descriptor of the given {@code element}.
*
* This is useful for matching Kotlin Metadata JVM Signatures with elements from the AST.
*
*
For reference, see the JVM
* specification, section 4.3.2.
*/
public static String getFieldDescriptor(VariableElement element) {
return element.getSimpleName() + ":" + getDescriptor(element.asType());
}
/**
* Returns the method descriptor of the given {@code element}.
*
*
This is useful for matching Kotlin Metadata JVM Signatures with elements from the AST.
*
*
For reference, see the JVM
* specification, section 4.3.3.
*/
public static String getMethodDescriptor(ExecutableElement element) {
return element.getSimpleName() + getDescriptor(element.asType());
}
private static String getDescriptor(TypeMirror t) {
return t.accept(JVM_DESCRIPTOR_TYPE_VISITOR, null);
}
private static final AbstractTypeVisitor8 JVM_DESCRIPTOR_TYPE_VISITOR =
new AbstractTypeVisitor8() {
@Override
public String visitArray(ArrayType arrayType, Void v) {
return "[" + getDescriptor(arrayType.getComponentType());
}
@Override
public String visitDeclared(DeclaredType declaredType, Void v) {
return "L" + getInternalName(declaredType.asElement()) + ";";
}
@Override
public String visitError(ErrorType errorType, Void v) {
// For descriptor generating purposes we don't need a fully modeled type since we are
// only interested in obtaining the class name in its "internal form".
return visitDeclared(errorType, v);
}
@Override
public String visitExecutable(ExecutableType executableType, Void v) {
String parameterDescriptors =
executableType.getParameterTypes().stream()
.map(DaggerElements::getDescriptor)
.collect(Collectors.joining());
String returnDescriptor = getDescriptor(executableType.getReturnType());
return "(" + parameterDescriptors + ")" + returnDescriptor;
}
@Override
public String visitIntersection(IntersectionType intersectionType, Void v) {
// For a type variable with multiple bounds: "the erasure of a type variable is determined
// by the first type in its bound" - JVM Spec Sec 4.4
return getDescriptor(intersectionType.getBounds().get(0));
}
@Override
public String visitNoType(NoType noType, Void v) {
return "V";
}
@Override
public String visitNull(NullType nullType, Void v) {
return visitUnknown(nullType, null);
}
@Override
public String visitPrimitive(PrimitiveType primitiveType, Void v) {
switch (primitiveType.getKind()) {
case BOOLEAN:
return "Z";
case BYTE:
return "B";
case SHORT:
return "S";
case INT:
return "I";
case LONG:
return "J";
case CHAR:
return "C";
case FLOAT:
return "F";
case DOUBLE:
return "D";
default:
throw new IllegalArgumentException("Unknown primitive type.");
}
}
@Override
public String visitTypeVariable(TypeVariable typeVariable, Void v) {
// The erasure of a type variable is the erasure of its leftmost bound. - JVM Spec Sec 4.6
return getDescriptor(typeVariable.getUpperBound());
}
@Override
public String visitUnion(UnionType unionType, Void v) {
return visitUnknown(unionType, null);
}
@Override
public String visitUnknown(TypeMirror typeMirror, Void v) {
throw new IllegalArgumentException("Unsupported type: " + typeMirror);
}
@Override
public String visitWildcard(WildcardType wildcardType, Void v) {
return "";
}
/**
* Returns the name of this element in its "internal form".
*
* For reference, see the JVM
* specification, section 4.2.
*/
private String getInternalName(Element element) {
try {
TypeElement typeElement = MoreElements.asType(element);
switch (typeElement.getNestingKind()) {
case TOP_LEVEL:
return typeElement.getQualifiedName().toString().replace('.', '/');
case MEMBER:
return getInternalName(typeElement.getEnclosingElement())
+ "$"
+ typeElement.getSimpleName();
default:
throw new IllegalArgumentException("Unsupported nesting kind.");
}
} catch (IllegalArgumentException e) {
// Not a TypeElement, try something else...
}
if (element instanceof QualifiedNameable) {
QualifiedNameable qualifiedNameElement = (QualifiedNameable) element;
return qualifiedNameElement.getQualifiedName().toString().replace('.', '/');
}
return element.getSimpleName().toString();
}
};
/**
* Invokes {@link Elements#getTypeElement(CharSequence)}, throwing {@link TypeNotPresentException}
* if it is not accessible in the current compilation.
*/
public TypeElement checkTypePresent(String typeName) {
TypeElement type = elements.getTypeElement(typeName);
if (type == null) {
throw new TypeNotPresentException(typeName, null);
}
return type;
}
@Override
public PackageElement getPackageElement(CharSequence name) {
return elements.getPackageElement(name);
}
@Override
public Map getElementValuesWithDefaults(
AnnotationMirror a) {
return elements.getElementValuesWithDefaults(a);
}
/** Returns a map of annotation values keyed by attribute name. */
public Map getElementValuesWithDefaultsByName(
AnnotationMirror a) {
ImmutableMap.Builder builder = ImmutableMap.builder();
getElementValuesWithDefaults(a).forEach((k, v) -> builder.put(k.getSimpleName().toString(), v));
return builder.build();
}
@Override
public String getDocComment(Element e) {
return elements.getDocComment(e);
}
@Override
public boolean isDeprecated(Element e) {
return elements.isDeprecated(e);
}
@Override
public Name getBinaryName(TypeElement type) {
return elements.getBinaryName(type);
}
@Override
public PackageElement getPackageOf(Element type) {
return elements.getPackageOf(type);
}
@Override
public List getAllMembers(TypeElement type) {
return elements.getAllMembers(type);
}
@Override
public List getAllAnnotationMirrors(Element e) {
return elements.getAllAnnotationMirrors(e);
}
@Override
public boolean hides(Element hider, Element hidden) {
return elements.hides(hider, hidden);
}
@Override
public boolean overrides(
ExecutableElement overrider, ExecutableElement overridden, TypeElement type) {
return elements.overrides(overrider, overridden, type);
}
@Override
public String getConstantExpression(Object value) {
return elements.getConstantExpression(value);
}
@Override
public void printElements(Writer w, Element... elements) {
this.elements.printElements(w, elements);
}
@Override
public Name getName(CharSequence cs) {
return elements.getName(cs);
}
@Override
public boolean isFunctionalInterface(TypeElement type) {
return elements.isFunctionalInterface(type);
}
@Override
public void clearCache() {
getLocalAndInheritedMethodsCache.clear();
}
}