001// License: GPL. For details, see LICENSE file. 002package org.openstreetmap.josm.data.imagery; 003 004import java.util.concurrent.ThreadPoolExecutor; 005import java.util.concurrent.TimeUnit; 006 007import org.apache.commons.jcs.access.behavior.ICacheAccess; 008import org.openstreetmap.gui.jmapviewer.Tile; 009import org.openstreetmap.gui.jmapviewer.interfaces.CachedTileLoader; 010import org.openstreetmap.gui.jmapviewer.interfaces.TileJob; 011import org.openstreetmap.gui.jmapviewer.interfaces.TileLoader; 012import org.openstreetmap.gui.jmapviewer.interfaces.TileLoaderListener; 013import org.openstreetmap.gui.jmapviewer.interfaces.TileSource; 014import org.openstreetmap.josm.data.cache.BufferedImageCacheEntry; 015import org.openstreetmap.josm.data.cache.HostLimitQueue; 016import org.openstreetmap.josm.data.preferences.IntegerProperty; 017import org.openstreetmap.josm.tools.CheckParameterUtil; 018import org.openstreetmap.josm.tools.Utils; 019 020/** 021 * Wrapper class that bridges between JCS cache and Tile Loaders 022 * 023 * @author Wiktor Niesiobędzki 024 */ 025public class TMSCachedTileLoader implements TileLoader, CachedTileLoader { 026 027 protected final ICacheAccess<String, BufferedImageCacheEntry> cache; 028 protected final TileLoaderListener listener; 029 030 /** 031 * overrides the THREAD_LIMIT in superclass, as we want to have separate limit and pool for TMS 032 */ 033 034 public static final IntegerProperty THREAD_LIMIT = new IntegerProperty("imagery.tms.tmsloader.maxjobs", 25); 035 036 /** 037 * Limit definition for per host concurrent connections 038 */ 039 public static final IntegerProperty HOST_LIMIT = new IntegerProperty("imagery.tms.tmsloader.maxjobsperhost", 6); 040 041 /** 042 * separate from JCS thread pool for TMS loader, so we can have different thread pools for default JCS 043 * and for TMS imagery 044 */ 045 private static final ThreadPoolExecutor DEFAULT_DOWNLOAD_JOB_DISPATCHER = getNewThreadPoolExecutor("TMS-downloader-%d"); 046 047 private ThreadPoolExecutor downloadExecutor = DEFAULT_DOWNLOAD_JOB_DISPATCHER; 048 protected final TileJobOptions options; 049 050 /** 051 * Constructor 052 * @param listener called when tile loading has finished 053 * @param cache of the cache 054 * @param options tile job options 055 */ 056 public TMSCachedTileLoader(TileLoaderListener listener, ICacheAccess<String, BufferedImageCacheEntry> cache, 057 TileJobOptions options) { 058 CheckParameterUtil.ensureParameterNotNull(cache, "cache"); 059 this.cache = cache; 060 this.options = options; 061 this.listener = listener; 062 } 063 064 /** 065 * @param nameFormat see {@link Utils#newThreadFactory(String, int)} 066 * @param workers number of worker thread to keep 067 * @return new ThreadPoolExecutor that will use a @see HostLimitQueue based queue 068 */ 069 public static ThreadPoolExecutor getNewThreadPoolExecutor(String nameFormat, int workers) { 070 HostLimitQueue workQueue = new HostLimitQueue(HOST_LIMIT.get().intValue()); 071 ThreadPoolExecutor executor = new ThreadPoolExecutor( 072 0, // 0 so for unused thread pools threads will eventually die, freeing also the threadpool 073 workers, // do not this number of threads 074 300, // keepalive for thread 075 TimeUnit.SECONDS, 076 workQueue, 077 Utils.newThreadFactory(nameFormat, Thread.NORM_PRIORITY) 078 ); 079 workQueue.setExecutor(executor); 080 return executor; 081 } 082 083 /** 084 * @param name name of threads 085 * @return new ThreadPoolExecutor that will use a @see HostLimitQueue based queue, with default number of threads 086 */ 087 public static ThreadPoolExecutor getNewThreadPoolExecutor(String name) { 088 return getNewThreadPoolExecutor(name, THREAD_LIMIT.get().intValue()); 089 } 090 091 @Override 092 public TileJob createTileLoaderJob(Tile tile) { 093 return new TMSCachedTileLoaderJob( 094 listener, 095 tile, 096 cache, 097 options, 098 getDownloadExecutor()); 099 } 100 101 @Override 102 public void clearCache(TileSource source) { 103 this.cache.remove(source.getName() + ':'); 104 } 105 106 /** 107 * @return cache statistics as string 108 */ 109 public String getStats() { 110 return cache.getStats(); 111 } 112 113 /** 114 * cancels all outstanding tasks in the queue. This rollbacks the state of the tiles in the queue 115 * to loading = false / loaded = false 116 */ 117 @Override 118 public void cancelOutstandingTasks() { 119 for (Runnable r: downloadExecutor.getQueue()) { 120 if (downloadExecutor.remove(r) && r instanceof TMSCachedTileLoaderJob) { 121 ((TMSCachedTileLoaderJob) r).handleJobCancellation(); 122 } 123 } 124 } 125 126 @Override 127 public boolean hasOutstandingTasks() { 128 return downloadExecutor.getTaskCount() > downloadExecutor.getCompletedTaskCount(); 129 } 130 131 /** 132 * Sets the download executor that will be used to download tiles instead of default one. 133 * You can use {@link #getNewThreadPoolExecutor} to create a new download executor with separate 134 * queue from default. 135 * 136 * @param downloadExecutor download executor that will be used to download tiles 137 */ 138 public void setDownloadExecutor(ThreadPoolExecutor downloadExecutor) { 139 this.downloadExecutor = downloadExecutor; 140 } 141 142 /** 143 * @return download executor that is used by this factory 144 */ 145 public ThreadPoolExecutor getDownloadExecutor() { 146 return downloadExecutor; 147 } 148}