001/*
002 * Copyright (c) 2012, Oracle and/or its affiliates. All rights reserved.
003 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
004 *
005 * This code is free software; you can redistribute it and/or modify it
006 * under the terms of the GNU General Public License version 2 only, as
007 * published by the Free Software Foundation.
008 *
009 * This code is distributed in the hope that it will be useful, but WITHOUT
010 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
011 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
012 * version 2 for more details (a copy is included in the LICENSE file that
013 * accompanied this code).
014 *
015 * You should have received a copy of the GNU General Public License version
016 * 2 along with this work; if not, write to the Free Software Foundation,
017 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
018 *
019 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
020 * or visit www.oracle.com if you need additional information or have any
021 * questions.
022 */
023package com.oracle.graal.debug;
024
025/**
026 * A counter for some value of interest.
027 */
028public interface DebugMetric {
029
030    /**
031     * Adds 1 to this counter if metering is {@link Debug#isMeterEnabled() enabled} or this is an
032     * {@linkplain #isConditional() unconditional} metric.
033     */
034    void increment();
035
036    /**
037     * Adds {@code value} to this counter if metering is {@link Debug#isMeterEnabled() enabled} or
038     * this is an {@linkplain #isConditional() unconditional} metric.
039     */
040    void add(long value);
041
042    /**
043     * Sets a flag determining if this counter is only enabled if metering is
044     * {@link Debug#isMeterEnabled() enabled}.
045     */
046    void setConditional(boolean flag);
047
048    /**
049     * Determines if this counter is only enabled if metering is {@link Debug#isMeterEnabled()
050     * enabled}.
051     */
052    boolean isConditional();
053
054    /**
055     * Gets the current value of this metric.
056     */
057    long getCurrentValue();
058
059    /**
060     * Determines if this counter is enabled (either conditionally or unconditionally).
061     */
062    default boolean isEnabled() {
063        return !isConditional() || Debug.isMeterEnabled();
064    }
065}