com.google.errorprone.bugpatterns.collectionincompatibletype.MethodArgMatcher Maven / Gradle / Ivy
/*
* Copyright 2015 The Error Prone 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 com.google.errorprone.bugpatterns.collectionincompatibletype;
import static com.google.errorprone.matchers.method.MethodMatchers.instanceMethod;
import static com.google.errorprone.util.ASTHelpers.getType;
import com.google.common.collect.Iterables;
import com.google.errorprone.VisitorState;
import com.google.errorprone.fixes.Fix;
import com.google.errorprone.fixes.SuggestedFix;
import com.google.errorprone.matchers.Matcher;
import com.google.errorprone.util.ASTHelpers;
import com.sun.source.tree.ExpressionTree;
import com.sun.source.tree.MemberReferenceTree;
import com.sun.source.tree.MethodInvocationTree;
import com.sun.tools.javac.code.Type;
import java.util.Collection;
import java.util.Optional;
import javax.annotation.Nullable;
/**
* Matches an instance method like {@link Collection#contains}, for which we just need to compare
* the method argument's type to the receiver's type argument. This is the common case.
*/
final class MethodArgMatcher extends AbstractCollectionIncompatibleTypeMatcher {
private final Matcher methodMatcher;
private final String typeName;
private final int typeArgIndex;
private final int methodArgIndex;
/**
* @param typeName The fully-qualified name of the type whose descendants to match on
* @param signature The signature of the method to match on
* @param typeArgIndex The index of the type argument that should match the method argument
* @param methodArgIndex The index of the method argument that should match the type argument
*/
MethodArgMatcher(String typeName, String signature, int typeArgIndex, int methodArgIndex) {
this.methodMatcher = instanceMethod().onDescendantOf(typeName).withSignature(signature);
this.typeName = typeName;
this.typeArgIndex = typeArgIndex;
this.methodArgIndex = methodArgIndex;
}
@Override
Matcher methodMatcher() {
return methodMatcher;
}
@Override
ExpressionTree extractSourceTree(MethodInvocationTree tree, VisitorState state) {
return Iterables.get(tree.getArguments(), methodArgIndex);
}
@Nullable
@Override
ExpressionTree extractSourceTree(MemberReferenceTree tree, VisitorState state) {
return tree;
}
@Override
Type extractSourceType(MethodInvocationTree tree, VisitorState state) {
return getType(extractSourceTree(tree, state));
}
@Nullable
@Override
Type extractSourceType(MemberReferenceTree tree, VisitorState state) {
return state.getTypes().findDescriptorType(getType(tree)).getParameterTypes().get(0);
}
@Override
Type extractTargetType(MethodInvocationTree tree, VisitorState state) {
return extractTypeArgAsMemberOfSupertype(
ASTHelpers.getReceiverType(tree),
state.getSymbolFromString(typeName),
typeArgIndex,
state.getTypes());
}
@Nullable
@Override
Type extractTargetType(MemberReferenceTree tree, VisitorState state) {
return extractTypeArgAsMemberOfSupertype(
ASTHelpers.getReceiverType(tree),
state.getSymbolFromString(typeName),
typeArgIndex,
state.getTypes());
}
@Override
Optional buildFix(MatchResult result) {
return Optional.of(SuggestedFix.prefixWith(result.sourceTree(), "(Object) "));
}
@Override
public String message(MatchResult result, String sourceType, String targetType) {
return String.format(
"Argument '%s' should not be passed to this method; its type %s is not compatible "
+ "with its collection's type argument %s",
result.sourceTree(), sourceType, targetType);
}
}