001////////////////////////////////////////////////////////////////////////////////
002// checkstyle: Checks Java source code for adherence to a set of rules.
003// Copyright (C) 2001-2021 the original author or authors.
004//
005// This library is free software; you can redistribute it and/or
006// modify it under the terms of the GNU Lesser General Public
007// License as published by the Free Software Foundation; either
008// version 2.1 of the License, or (at your option) any later version.
009//
010// This library is distributed in the hope that it will be useful,
011// but WITHOUT ANY WARRANTY; without even the implied warranty of
012// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
013// Lesser General Public License for more details.
014//
015// You should have received a copy of the GNU Lesser General Public
016// License along with this library; if not, write to the Free Software
017// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
018////////////////////////////////////////////////////////////////////////////////
019
020package com.puppycrawl.tools.checkstyle.api;
021
022import java.util.concurrent.atomic.AtomicInteger;
023
024/**
025 * An audit listener that counts how many {@link AuditEvent AuditEvents}
026 * of a given severity have been generated.
027 *
028 */
029public final class SeverityLevelCounter implements AuditListener {
030
031    /** The severity level to watch out for. */
032    private final SeverityLevel level;
033
034    /** Keeps track of the number of counted events. */
035    private final AtomicInteger count = new AtomicInteger();
036
037    /**
038     * Creates a new counter.
039     *
040     * @param level the severity level events need to have, must be non-null.
041     * @throws IllegalArgumentException when level is null
042     */
043    public SeverityLevelCounter(SeverityLevel level) {
044        if (level == null) {
045            throw new IllegalArgumentException("'level' cannot be null");
046        }
047        this.level = level;
048    }
049
050    @Override
051    public void addError(AuditEvent event) {
052        if (level == event.getSeverityLevel()) {
053            count.incrementAndGet();
054        }
055    }
056
057    @Override
058    public void addException(AuditEvent event, Throwable throwable) {
059        if (level == SeverityLevel.ERROR) {
060            count.incrementAndGet();
061        }
062    }
063
064    @Override
065    public void auditStarted(AuditEvent event) {
066        count.set(0);
067    }
068
069    @Override
070    public void fileStarted(AuditEvent event) {
071        // No code by default, should be overridden only by demand at subclasses
072    }
073
074    @Override
075    public void auditFinished(AuditEvent event) {
076        // No code by default, should be overridden only by demand at subclasses
077    }
078
079    @Override
080    public void fileFinished(AuditEvent event) {
081        // No code by default, should be overridden only by demand at subclasses
082    }
083
084    /**
085     * Returns the number of counted events since audit started.
086     *
087     * @return the number of counted events since audit started.
088     */
089    public int getCount() {
090        return count.get();
091    }
092
093}