// Might throw.
private SQLiteConnection tryAcquireNonPrimaryConnectionLocked(String sql, int connectionFlags) {
// Try to acquire the next connection in the queue.
SQLiteConnection connection;
final int availableCount = mAvailableNonPrimaryConnections.size();
if (availableCount > 1 && sql != null) {
// If we have a choice, then prefer a connection that has the
// prepared statement in its cache.
for (int i = 0; i < availableCount; i++) {
connection = mAvailableNonPrimaryConnections.get(i);
if (connection.isPreparedStatementInCache(sql)) {
mAvailableNonPrimaryConnections.remove(i);
finishAcquireConnectionLocked(connection, connectionFlags); // might throw
return connection;
}
}
}
if (availableCount > 0) {
// Otherwise, just grab the next one.
connection = mAvailableNonPrimaryConnections.remove(availableCount - 1);
finishAcquireConnectionLocked(connection, connectionFlags); // might throw
return connection;
}
// Expand the pool if needed.
int openConnections = mAcquiredConnections.size();
if (mAvailablePrimaryConnection != null) {
openConnections += 1;
}
if (openConnections >= mMaxConnectionPoolSize) {
return null;
}
connection = openConnectionLocked(mConfiguration, false /*primaryConnection*/); // might throw
finishAcquireConnectionLocked(connection, connectionFlags); // might throw
return connection;
}
@SuppressWarnings("unchecked")
public static <T> MethodCapturer<T> capture(T obj) {
synchronized (s_cache) {
MethodCapturer<T> capturer = (MethodCapturer<T>) s_cache.get(obj);
if (capturer != null) {
return capturer;
}
final MethodCapturer<T> capturerNew = new MethodCapturer<T>();
Enhancer en = new Enhancer();
en.setSuperclass(obj.getClass());
en.setCallbacks(
new Callback[] {
new MethodInterceptor() {
@Override
public Object intercept(Object arg0, Method arg1, Object[] arg2, MethodProxy arg3)
throws Throwable {
capturerNew.setMethod(arg1);
return null;
}
},
new MethodInterceptor() {
@Override
public Object intercept(Object arg0, Method arg1, Object[] arg2, MethodProxy arg3)
throws Throwable {
return null;
}
}
});
en.setCallbackFilter(
new CallbackFilter() {
@Override
public int accept(Method method) {
if (method.getParameterTypes().length == 0 && method.getName().equals("finalize")) {
return 1;
}
return 0;
}
});
capturerNew.setInstance((T) en.create());
// We expect MethodCapturer is only used for singleton objects here, so we only maintain a
// limited cache
// here
if (s_cache.size() < CACHE_SIZE) {
s_cache.put(obj, capturerNew);
}
return capturerNew;
}
}
public static void main(String[] args) {
WeakHashMap<String, String> map = new WeakHashMap<String, String>();
// 测试数据
// 常量池对象不会回收
map.put("abc", "a");
map.put("d", "tets");
// gc运行已被回收
map.put(new String(""), "d");
// 通知回收
System.gc();
System.runFinalization();
System.out.println(map.size());
}
// Can't throw.
private void markAcquiredConnectionsLocked(AcquiredConnectionStatus status) {
if (!mAcquiredConnections.isEmpty()) {
ArrayList<SQLiteConnection> keysToUpdate =
new ArrayList<SQLiteConnection>(mAcquiredConnections.size());
for (Map.Entry<SQLiteConnection, AcquiredConnectionStatus> entry :
mAcquiredConnections.entrySet()) {
AcquiredConnectionStatus oldStatus = entry.getValue();
if (status != oldStatus && oldStatus != AcquiredConnectionStatus.DISCARD) {
keysToUpdate.add(entry.getKey());
}
}
final int updateCount = keysToUpdate.size();
for (int i = 0; i < updateCount; i++) {
mAcquiredConnections.put(keysToUpdate.get(i), status);
}
}
}
private void dispose(boolean finalized) {
if (mCloseGuard != null) {
if (finalized) {
mCloseGuard.warnIfOpen();
}
mCloseGuard.close();
}
if (!finalized) {
// Close all connections. We don't need (or want) to do this
// when finalized because we don't know what state the connections
// themselves will be in. The finalizer is really just here for CloseGuard.
// The connections will take care of themselves when their own finalizers run.
synchronized (mLock) {
throwIfClosedLocked();
mIsOpen = false;
closeAvailableConnectionsAndLogExceptionsLocked();
final int pendingCount = mAcquiredConnections.size();
if (pendingCount != 0) {
Log.i(
TAG,
"The connection pool for "
+ mConfiguration.label
+ " has been closed but there are still "
+ pendingCount
+ " connections in use. They will be closed "
+ "as they are released back to the pool.");
}
wakeConnectionWaitersLocked();
}
}
}
@NotNull
public Object[] getToExpand() {
return myToExpand.keySet().toArray(new Object[myToExpand.size()]);
}
@NotNull
public Object[] getToSelect() {
return myToSelect.keySet().toArray(new Object[myToSelect.size()]);
}