Merge "Frameworks: Move SharedPreferencesImpl to Future"
diff --git a/core/java/android/app/SharedPreferencesImpl.java b/core/java/android/app/SharedPreferencesImpl.java
index 97187d6..389ae71 100644
--- a/core/java/android/app/SharedPreferencesImpl.java
+++ b/core/java/android/app/SharedPreferencesImpl.java
@@ -50,6 +50,11 @@
import java.util.Set;
import java.util.WeakHashMap;
import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.Future;
+import java.util.concurrent.FutureTask;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.TimeoutException;
final class SharedPreferencesImpl implements SharedPreferences {
private static final String TAG = "SharedPreferencesImpl";
@@ -69,16 +74,12 @@
private final Object mLock = new Object();
private final Object mWritingToDiskLock = new Object();
- @GuardedBy("mLock")
- private Map<String, Object> mMap;
+ private Future<Map<String, Object>> mMap;
@GuardedBy("mLock")
private int mDiskWritesInFlight = 0;
@GuardedBy("mLock")
- private boolean mLoaded = false;
-
- @GuardedBy("mLock")
private StructTimespec mStatTimestamp;
@GuardedBy("mLock")
@@ -105,27 +106,18 @@
mFile = file;
mBackupFile = makeBackupFile(file);
mMode = mode;
- mLoaded = false;
mMap = null;
startLoadFromDisk();
}
private void startLoadFromDisk() {
- synchronized (mLock) {
- mLoaded = false;
- }
- new Thread("SharedPreferencesImpl-load") {
- public void run() {
- loadFromDisk();
- }
- }.start();
+ FutureTask<Map<String, Object>> futureTask = new FutureTask<>(() -> loadFromDisk());
+ mMap = futureTask;
+ new Thread(futureTask, "SharedPreferencesImpl-load").start();
}
- private void loadFromDisk() {
+ private Map<String, Object> loadFromDisk() {
synchronized (mLock) {
- if (mLoaded) {
- return;
- }
if (mBackupFile.exists()) {
mFile.delete();
mBackupFile.renameTo(mFile);
@@ -158,16 +150,14 @@
}
synchronized (mLock) {
- mLoaded = true;
if (map != null) {
- mMap = map;
mStatTimestamp = stat.st_mtim;
mStatSize = stat.st_size;
} else {
- mMap = new HashMap<>();
+ map = new HashMap<>();
}
- mLock.notifyAll();
}
+ return map;
}
static File makeBackupFile(File prefsFile) {
@@ -226,36 +216,37 @@
}
}
- private void awaitLoadedLocked() {
- if (!mLoaded) {
+ private @GuardedBy("mLock") Map<String, Object> getLoaded() {
+ try {
+ return mMap.get();
+ } catch (InterruptedException | ExecutionException e) {
+ throw new IllegalStateException(e);
+ }
+ }
+ private @GuardedBy("mLock") Map<String, Object> getLoadedWithBlockGuard() {
+ if (!mMap.isDone()) {
// Raise an explicit StrictMode onReadFromDisk for this
// thread, since the real read will be in a different
// thread and otherwise ignored by StrictMode.
BlockGuard.getThreadPolicy().onReadFromDisk();
}
- while (!mLoaded) {
- try {
- mLock.wait();
- } catch (InterruptedException unused) {
- }
- }
+ return getLoaded();
}
@Override
public Map<String, ?> getAll() {
+ Map<String, Object> map = getLoadedWithBlockGuard();
synchronized (mLock) {
- awaitLoadedLocked();
- //noinspection unchecked
- return new HashMap<String, Object>(mMap);
+ return new HashMap<String, Object>(map);
}
}
@Override
@Nullable
public String getString(String key, @Nullable String defValue) {
+ Map<String, Object> map = getLoadedWithBlockGuard();
synchronized (mLock) {
- awaitLoadedLocked();
- String v = (String)mMap.get(key);
+ String v = (String) map.get(key);
return v != null ? v : defValue;
}
}
@@ -263,66 +254,65 @@
@Override
@Nullable
public Set<String> getStringSet(String key, @Nullable Set<String> defValues) {
+ Map<String, Object> map = getLoadedWithBlockGuard();
synchronized (mLock) {
- awaitLoadedLocked();
- Set<String> v = (Set<String>) mMap.get(key);
+ @SuppressWarnings("unchecked")
+ Set<String> v = (Set<String>) map.get(key);
return v != null ? v : defValues;
}
}
@Override
public int getInt(String key, int defValue) {
+ Map<String, Object> map = getLoadedWithBlockGuard();
synchronized (mLock) {
- awaitLoadedLocked();
- Integer v = (Integer)mMap.get(key);
+ Integer v = (Integer) map.get(key);
return v != null ? v : defValue;
}
}
@Override
public long getLong(String key, long defValue) {
+ Map<String, Object> map = getLoadedWithBlockGuard();
synchronized (mLock) {
- awaitLoadedLocked();
- Long v = (Long)mMap.get(key);
+ Long v = (Long) map.get(key);
return v != null ? v : defValue;
}
}
@Override
public float getFloat(String key, float defValue) {
+ Map<String, Object> map = getLoadedWithBlockGuard();
synchronized (mLock) {
- awaitLoadedLocked();
- Float v = (Float)mMap.get(key);
+ Float v = (Float) map.get(key);
return v != null ? v : defValue;
}
}
@Override
public boolean getBoolean(String key, boolean defValue) {
+ Map<String, Object> map = getLoadedWithBlockGuard();
synchronized (mLock) {
- awaitLoadedLocked();
- Boolean v = (Boolean)mMap.get(key);
+ Boolean v = (Boolean) map.get(key);
return v != null ? v : defValue;
}
}
@Override
public boolean contains(String key) {
+ Map<String, Object> map = getLoadedWithBlockGuard();
synchronized (mLock) {
- awaitLoadedLocked();
- return mMap.containsKey(key);
+ return map.containsKey(key);
}
}
@Override
public Editor edit() {
- // TODO: remove the need to call awaitLoadedLocked() when
+ // TODO: remove the need to call getLoaded() when
// requesting an editor. will require some work on the
// Editor, but then we should be able to do:
//
// context.getSharedPreferences(..).edit().putString(..).apply()
//
// ... all without blocking.
- synchronized (mLock) {
- awaitLoadedLocked();
- }
+ getLoadedWithBlockGuard();
return new EditorImpl();
}
@@ -476,13 +466,43 @@
// a memory commit comes in when we're already
// writing to disk.
if (mDiskWritesInFlight > 0) {
- // We can't modify our mMap as a currently
+ // We can't modify our map as a currently
// in-flight write owns it. Clone it before
// modifying it.
// noinspection unchecked
- mMap = new HashMap<String, Object>(mMap);
+ mMap = new Future<Map<String, Object>>() {
+ private Map<String, Object> mCopiedMap =
+ new HashMap<String, Object>(getLoaded());
+
+ @Override
+ public boolean cancel(boolean mayInterruptIfRunning) {
+ return false;
+ }
+
+ @Override
+ public boolean isCancelled() {
+ return false;
+ }
+
+ @Override
+ public boolean isDone() {
+ return true;
+ }
+
+ @Override
+ public Map<String, Object> get()
+ throws InterruptedException, ExecutionException {
+ return mCopiedMap;
+ }
+
+ @Override
+ public Map<String, Object> get(long timeout, TimeUnit unit)
+ throws InterruptedException, ExecutionException, TimeoutException {
+ return mCopiedMap;
+ }
+ };
}
- mapToWriteToDisk = mMap;
+ mapToWriteToDisk = getLoaded();
mDiskWritesInFlight++;
boolean hasListeners = mListeners.size() > 0;