com.google.errorprone.bugpatterns.time.JavaDurationWithNanos.java Source code

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Here is the source code for com.google.errorprone.bugpatterns.time.JavaDurationWithNanos.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.time;

import static com.google.errorprone.BugPattern.ProvidesFix.REQUIRES_HUMAN_ATTENTION;
import static com.google.errorprone.BugPattern.SeverityLevel.WARNING;
import static com.google.errorprone.matchers.Matchers.allOf;
import static com.google.errorprone.matchers.Matchers.not;
import static com.google.errorprone.matchers.Matchers.packageStartsWith;

import com.google.common.collect.Iterables;
import com.google.errorprone.BugPattern;
import com.google.errorprone.VisitorState;
import com.google.errorprone.bugpatterns.BugChecker;
import com.google.errorprone.bugpatterns.BugChecker.MethodInvocationTreeMatcher;
import com.google.errorprone.fixes.SuggestedFix;
import com.google.errorprone.fixes.SuggestedFixes;
import com.google.errorprone.matchers.Description;
import com.google.errorprone.matchers.Matcher;
import com.google.errorprone.matchers.Matchers;
import com.google.errorprone.util.ASTHelpers;
import com.sun.source.tree.ExpressionTree;
import com.sun.source.tree.MethodInvocationTree;
import com.sun.tools.javac.tree.JCTree;

/** Check for calls to {@code duration.withNanos(int)}. */
@BugPattern(name = "JavaDurationWithNanos", summary = "Use of java.time.Duration.withNanos(int) is not allowed.", explanation = "Duration's withNanos(int) method is often a source of bugs because it returns a copy of "
        + "the current Duration instance, but _only_ the nano field is mutated (the seconds "
        + "field is copied directly). Use Duration.ofSeconds(duration.getSeconds(), nanos) "
        + "instead.", severity = WARNING, providesFix = REQUIRES_HUMAN_ATTENTION)
public final class JavaDurationWithNanos extends BugChecker implements MethodInvocationTreeMatcher {

    private static final Matcher<ExpressionTree> MATCHER = allOf(
            Matchers.instanceMethod().onExactClass("java.time.Duration").named("withNanos").withParameters("int"),
            // Allow usage by java.time itself
            not(packageStartsWith("java.time")));

    @Override
    public Description matchMethodInvocation(MethodInvocationTree tree, VisitorState state) {
        if (!MATCHER.matches(tree, state)) {
            return Description.NO_MATCH;
        }

        SuggestedFix.Builder builder = SuggestedFix.builder();
        ExpressionTree nanosArg = Iterables.getOnlyElement(tree.getArguments());
        ExpressionTree receiver = ASTHelpers.getReceiver(tree);
        String replacement = SuggestedFixes.qualifyType(state, builder, "java.time.Duration") + ".ofSeconds("
                + state.getSourceForNode(receiver) + ".getSeconds(), ";

        builder.replace(((JCTree) tree).getStartPosition(), ((JCTree) nanosArg).getStartPosition(), replacement);
        return describeMatch(tree, builder.build());
    }
}