001/*
002 * (C) Copyright 2006-2009 Nuxeo SA (http://nuxeo.com/) and others.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *     http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 *
016 * Contributors:
017 *     Nuxeo - initial API and implementation
018 *
019 * $Id$
020 */
021package org.nuxeo.runtime.management.counters;
022
023import java.util.Iterator;
024import java.util.LinkedList;
025
026/**
027 * Fixed length Stack that is used to store values of a counter over time
028 *
029 * @author Tiry (tdelprat@nuxeo.com)
030 * @deprecated since 11.4: use dropwizard metrics instead
031 */
032@Deprecated(since = "11.4")
033public class CounterHistoryStack implements Iterable<long[]> {
034
035    protected final LinkedList<long[]> list = new LinkedList<>();
036
037    protected final int maxSize;
038
039    public CounterHistoryStack(int size) {
040        maxSize = size;
041    }
042
043    public synchronized void push(long[] item) {
044        list.push(item);
045        if (list.size() > maxSize) {
046            list.remove(list.size() - 1);
047        }
048    }
049
050    @Override
051    public Iterator<long[]> iterator() {
052        return list.iterator();
053    }
054
055    @Override
056    public String toString() {
057        StringBuilder sb = new StringBuilder();
058
059        for (long[] entry : this) {
060            sb.append(entry[0]);
061            sb.append(" => ");
062            sb.append(entry[1]);
063            sb.append("\n");
064        }
065        return sb.toString();
066    }
067
068    public long[] get(int idx) {
069        return list.get(idx);
070    }
071
072    public LinkedList<long[]> getAsList() {
073        return list;
074    }
075}