com.google.errorprone.bugpatterns.CatchAndPrintStackTrace.java Source code

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Here is the source code for com.google.errorprone.bugpatterns.CatchAndPrintStackTrace.java

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/*
 * Copyright 2018 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.WARNING;
import static com.google.errorprone.matchers.Description.NO_MATCH;
import static com.google.errorprone.matchers.Matchers.expressionStatement;
import static com.google.errorprone.matchers.method.MethodMatchers.instanceMethod;

import com.google.common.collect.Iterables;
import com.google.errorprone.BugPattern;
import com.google.errorprone.VisitorState;
import com.google.errorprone.bugpatterns.BugChecker.CatchTreeMatcher;
import com.google.errorprone.matchers.Description;
import com.google.errorprone.matchers.Matcher;
import com.sun.source.tree.CatchTree;
import com.sun.source.tree.StatementTree;
import java.util.List;

/** @author cushon@google.com (Liam Miller-Cushon) */
@BugPattern(name = "CatchAndPrintStackTrace", summary = "Logging or rethrowing exceptions should usually be preferred to catching and calling"
        + " printStackTrace", severity = WARNING)
public class CatchAndPrintStackTrace extends BugChecker implements CatchTreeMatcher {

    private static final Matcher<StatementTree> MATCHER = expressionStatement(
            instanceMethod().onDescendantOf("java.lang.Throwable").named("printStackTrace"));

    @Override
    public Description matchCatch(CatchTree tree, VisitorState state) {
        List<? extends StatementTree> statements = tree.getBlock().getStatements();
        if (statements.size() != 1) {
            return NO_MATCH;
        }
        StatementTree statement = Iterables.getOnlyElement(statements);
        if (!MATCHER.matches(statement, state)) {
            return NO_MATCH;
        }
        return describeMatch(statement);
    }
}