com.google.errorprone.bugpatterns.ClassName 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;
import static com.google.errorprone.BugPattern.LinkType.CUSTOM;
import static com.google.errorprone.BugPattern.SeverityLevel.ERROR;
import com.google.common.base.Joiner;
import com.google.common.io.Files;
import com.google.errorprone.BugPattern;
import com.google.errorprone.VisitorState;
import com.google.errorprone.bugpatterns.BugChecker.CompilationUnitTreeMatcher;
import com.google.errorprone.matchers.Description;
import com.google.errorprone.util.ASTHelpers;
import com.sun.source.tree.ClassTree;
import com.sun.source.tree.CompilationUnitTree;
import com.sun.source.tree.Tree;
import java.util.ArrayList;
import java.util.List;
import javax.lang.model.element.Modifier;
/** A {@link BugChecker}; see the associated {@link BugPattern} annotation for details. */
@BugPattern(
name = "ClassName",
summary = "The source file name should match the name of the top-level class it contains",
severity = ERROR,
documentSuppression = false,
linkType = CUSTOM,
link = "https://google.github.io/styleguide/javaguide.html#s2.1-file-name")
public class ClassName extends BugChecker implements CompilationUnitTreeMatcher {
@Override
public Description matchCompilationUnit(CompilationUnitTree tree, VisitorState state) {
if (tree.getTypeDecls().isEmpty() || tree.getPackageName() == null) {
return Description.NO_MATCH;
}
String filename = Files.getNameWithoutExtension(ASTHelpers.getFileName(tree));
List names = new ArrayList<>();
for (Tree member : tree.getTypeDecls()) {
if (member instanceof ClassTree) {
ClassTree classMember = (ClassTree) member;
if (isSuppressed(classMember)) {
// If any top-level classes have @SuppressWarnings("ClassName"), ignore
// this compilation unit. We can't rely on the normal suppression
// mechanism because the only enclosing element is the package declaration,
// and @SuppressWarnings can't be applied to packages.
return Description.NO_MATCH;
}
if (classMember.getSimpleName().contentEquals(filename)) {
return Description.NO_MATCH;
}
if (classMember.getModifiers().getFlags().contains(Modifier.PUBLIC)) {
// If any of the top-level types are public, javac will complain
// if the filename doesn't match. We don't want to double-report
// the error.
return Description.NO_MATCH;
}
names.add(classMember.getSimpleName().toString());
}
}
String message =
String.format(
"Expected a class declaration named %s inside %s.java, instead found: %s",
filename, filename, Joiner.on(", ").join(names));
return buildDescription(tree.getPackageName()).setMessage(message).build();
}
}