adjustable cache size

Author: basinilya

res/values/strings.xml

@@ -61,6 +61,7 @@
     <string name="reconnect">Переподключаться</string>
     <string name="reconnect_count">Кол-во попыток</string>
     <string name="reconnect_timeout">Таймаут (сек)</string>
+    <string name="cache_size">Размер кэша (мин)</string>
 
     <string name="debug_preferences">Отладка</string>
     <string name="debug_log_enabled">Лог</string>

res/xml/preferences.xml

@@ -77,6 +77,15 @@
                 android:entryValues="@array/reconnect_timeout"
                 android:dialogTitle="@string/reconnect_timeout"/>
 
+        <EditTextPreference
+                android:key="cache_size_key"
+                android:numeric="integer"
+                android:maxLength="2"
+                android:defaultValue="5"
+                android:title="@string/cache_size"
+                android:dialogTitle="@string/cache_size"
+                />
+
     </android.preference.PreferenceCategory>
 
     <android.preference.PreferenceCategory android:title="@string/debug_preferences">

src/ru/piter/fm/activities/SettingsActivity.java

@@ -23,6 +23,7 @@ public class SettingsActivity extends PreferenceActivity implements SharedPrefer
     private CheckBoxPreference reconnectPref;
     private ListPreference reconnectCountPref;
     private ListPreference reconnectTimeoutPref;
+    private EditTextPreference cacheSizePref;
     private CheckBoxPreference debugLogPref;
 
     @Override
@@ -37,6 +38,12 @@ public void onCreate(Bundle savedInstanceState) {
         reconnectPref = (CheckBoxPreference) getPreferenceScreen().findPreference(Settings.RECONNECT);
         reconnectCountPref = (ListPreference) getPreferenceScreen().findPreference(Settings.RECONNECT_COUNT);
         reconnectTimeoutPref = (ListPreference) getPreferenceScreen().findPreference(Settings.RECONNECT_TIMEOUT);
+        cacheSizePref = (EditTextPreference) getPreferenceScreen().findPreference(Settings.CACHE_SIZE);
+        cacheSizePref.setOnPreferenceChangeListener(new Preference.OnPreferenceChangeListener() {@Override
+            public boolean onPreferenceChange(Preference preference, Object newValue) {
+                return Integer.parseInt((String) newValue) >= 2;
+            }
+        });
         debugLogPref = (CheckBoxPreference) getPreferenceScreen().findPreference(Settings.DEBUG_LOG_ENABLED);
         debugLogPref.setSummary(Utils.LOG_DIR.getAbsolutePath() + '/');
     }
@@ -57,6 +64,7 @@ protected void onResume() {
         reconnectPref.setSummary(Settings.isReconnect() ? on : off);
         reconnectCountPref.setSummary(String.valueOf(Settings.getReconnectCount()));
         reconnectTimeoutPref.setSummary(String.valueOf(Settings.getReconnectTimeout()));
+        cacheSizePref.setSummary(String.valueOf(Settings.getCacheSize()));
 
 
         getPreferenceScreen().getSharedPreferences().registerOnSharedPreferenceChangeListener(this);
@@ -90,6 +98,8 @@ public void onSharedPreferenceChanged(SharedPreferences sharedPreferences, Strin
             reconnectCountPref.setSummary(sharedPreferences.getString(Settings.RECONNECT_COUNT, "-1"));
         } else if (key.equals(Settings.RECONNECT_TIMEOUT)) {
             reconnectTimeoutPref.setSummary(sharedPreferences.getString(Settings.RECONNECT_TIMEOUT, "-1"));
+        } else if (key.equals(Settings.CACHE_SIZE)) {
+            cacheSizePref.setSummary(sharedPreferences.getString(Settings.CACHE_SIZE, "-1"));
         }
 
     }

src/ru/piter/fm/util/PiterFMCachingDownloader.java

@@ -98,9 +98,6 @@ public class PiterFMCachingDownloader {
     /** global object instance */
     public static final PiterFMCachingDownloader INSTANCE = new PiterFMCachingDownloader();
 
-    /** cache size */
-    private static final int READ_AHEAD_NUM = 10;
-
     /**
      * a dummy non-null value for {@link CacheEntry#m_url} to ensure the entry
      * is not picked by {@link #getFile(String, TrackCalendar)}. null can't be
@@ -114,26 +111,14 @@ public class PiterFMCachingDownloader {
     private final Object lock = new Object();
 
     /** holds queued URLs */
-    private ArrayList<String> urlQueue = new ArrayList<String>(READ_AHEAD_NUM);
+    private ArrayList<String> urlQueue = new ArrayList<String>();
 
     /** holds Cache Entries */
-    private CacheEntry[] entries = new CacheEntry[READ_AHEAD_NUM];
+    private ArrayList<CacheEntry> entries = new ArrayList<CacheEntry>();
 
     /** current URL for download. If differs from thread's URL, then thread waits. Can be null. */
     private String currentUrl;
 
-    /** constant map of entries by path. See also {@link #byUrl(String)} */
-    private final HashMap<String, CacheEntry> byPath = new HashMap<String, CacheEntry>(READ_AHEAD_NUM);
-
-    {
-        for (int i = 0; i < READ_AHEAD_NUM; i++) {
-            urlQueue.add(null);
-            CacheEntry entry = new CacheEntry(i);
-            entries[i] = entry;
-            byPath.put(entry.file.getAbsolutePath(), entry);
-        }
-    }
-
     /**
      * Get and lock a file with the provided params. This function is
      * synchronous and may block forever, if 5 other files stay locked.
@@ -148,13 +133,20 @@ public String getFile(String channelId, TrackCalendar trackTime) throws Interrup
             String trackUrl;
             // update the queue. Not queued entries may become victims, if not locked
             String prefix = CHANNEL_PREFIX + channelId + "/mp4/";
-            for (int i = 0;; i++) {
+            int cacheSize = Settings.getCacheSize();
+            urlQueue.clear();
+            urlQueue.ensureCapacity(cacheSize);
+            for (int i = cacheSize - 1;; i--) {
                 trackUrl = prefix + trackTime.asURLPart() + ".mp4";
-                urlQueue.set(i, trackUrl);
-                if (i == READ_AHEAD_NUM - 1)
+                urlQueue.add(trackUrl);
+                if (i == 0)
                     break;
                 trackTime.nextTrackTime();
             }
+            entries.ensureCapacity(cacheSize);
+            for (int i = entries.size(); i < cacheSize; i++) {
+                entries.add(new CacheEntry(i));
+            }
             resumeOrCreateNextDownloadNoLock();
             lock.notifyAll();
 
@@ -197,7 +189,8 @@ public void releaseFile(String path, boolean badFile) {
         Log.v(Tag, funcname + ",synchronized before, dummyNo:197"); try {
         synchronized (lock) {
             Log.v(Tag, funcname + ",synchronized in, dummyNo:199");
-            CacheEntry entry = byPath.get(path);
+            String sIndex = path.substring(path.lastIndexOf('/') + 1, path.length() - 4);
+            CacheEntry entry = entries.get(Integer.parseInt(sIndex));
             assertNull(entry.m_fos);
             assertTrue(entry.omniCount > 0);
             entry.omniCount--;
@@ -234,7 +227,10 @@ private void resumeOrCreateNextDownloadNoLock() {
 
             // rank victim candidates. null > scheduled > complete unrefed
             entry = null;
-            for (CacheEntry candidate : entries) {
+            // CacheEntry candidate : entries1
+            int cacheSize = urlQueue.size();
+            for (int i = 0; i < cacheSize; i++) {
+                CacheEntry candidate = entries.get(i);
                 if (candidate.m_url == null) {
                     entry = candidate; // best choice
                     break;

src/ru/piter/fm/util/Settings.java

@@ -22,6 +22,7 @@ public class Settings {
     public static final String RECONNECT = "reconnect_key";
     public static final String RECONNECT_COUNT = "reconnect_count_key";
     public static final String RECONNECT_TIMEOUT = "reconnect_timeout_key";
+    public static final String CACHE_SIZE = "cache_size_key";
     public static final String DEBUG_LOG_ENABLED = "debug_log_enabled_key";
 
 
@@ -72,4 +73,8 @@ public static int getReconnectCount(){
     public static int getReconnectTimeout(){
         return getInt(RECONNECT_TIMEOUT);
     }
+
+    public static int getCacheSize() {
+        return getInt(CACHE_SIZE);
+    }
 }