com.google.errorprone.bugpatterns.NCopiesOfChar Maven / Gradle / Ivy
/*
* Copyright 2017 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;
import static com.google.errorprone.BugPattern.SeverityLevel.ERROR;
import static com.google.errorprone.matchers.Description.NO_MATCH;
import static com.google.errorprone.matchers.method.MethodMatchers.staticMethod;
import static com.google.errorprone.util.ASTHelpers.getType;
import com.google.errorprone.BugPattern;
import com.google.errorprone.VisitorState;
import com.google.errorprone.bugpatterns.BugChecker.MethodInvocationTreeMatcher;
import com.google.errorprone.fixes.SuggestedFix;
import com.google.errorprone.matchers.Description;
import com.google.errorprone.matchers.Matcher;
import com.sun.source.tree.ExpressionTree;
import com.sun.source.tree.MethodInvocationTree;
import com.sun.tools.javac.code.Symtab;
import com.sun.tools.javac.code.Types;
import java.util.List;
/** A {@link BugChecker}; see the associated {@link BugPattern} annotation for details. */
@BugPattern(
summary =
"The first argument to nCopies is the number of copies, and the second is the item to copy",
severity = ERROR)
public class NCopiesOfChar extends BugChecker implements MethodInvocationTreeMatcher {
private static final Matcher MATCHER =
staticMethod().onClass("java.util.Collections").named("nCopies");
@Override
public Description matchMethodInvocation(MethodInvocationTree tree, VisitorState state) {
if (!MATCHER.matches(tree, state)) {
return NO_MATCH;
}
List arguments = tree.getArguments();
Symtab syms = state.getSymtab();
Types types = state.getTypes();
if (types.isSameType(types.unboxedTypeOrType(getType(arguments.get(1))), syms.intType)
&& types.isSameType(types.unboxedTypeOrType(getType(arguments.get(0))), syms.charType)) {
return describeMatch(
tree,
SuggestedFix.builder()
.replace(arguments.get(0), state.getSourceForNode(arguments.get(1)))
.replace(arguments.get(1), state.getSourceForNode(arguments.get(0)))
.build());
}
return NO_MATCH;
}
}