org.apache.http.impl.conn
Class SingleClientConnManager

java.lang.Object
  org.apache.http.impl.conn.SingleClientConnManager

All Implemented Interfaces:

ClientConnectionManager

@ThreadSafe
public class SingleClientConnManager
extends Object
implements ClientConnectionManager

A connection manager for a single connection. This connection manager maintains only one active connection at a time. Even though this class is thread-safe it ought to be used by one execution thread only.

SingleClientConnManager will make an effort to reuse the connection for subsequent requests with the same route. It will, however, close the existing connection and open it for the given route, if the route of the persistent connection does not match that of the connection request. If the connection has been already been allocated IllegalStateException is thrown.

Since:

4.0

Nested Class Summary

protected class	SingleClientConnManager.ConnAdapter The connection adapter used by this manager.
protected class	SingleClientConnManager.PoolEntry The pool entry for this connection manager.

Field Summary

protected boolean	alwaysShutDown Whether the connection should be shut down on release.
protected long	connectionExpiresTime The time the last released connection expires and shouldn't be reused.
protected ClientConnectionOperator	connOperator The operator for opening and updating connections.
protected boolean	isShutDown Indicates whether this connection manager is shut down.
protected long	lastReleaseTime The time of the last connection release, or -1.
protected SingleClientConnManager.ConnAdapter	managedConn The currently issued managed connection, if any.
static String	MISUSE_MESSAGE The message to be logged on multiple allocation.
protected SchemeRegistry	schemeRegistry The schemes supported by this connection manager.
protected SingleClientConnManager.PoolEntry	uniquePoolEntry The one and only entry in this pool.

Constructor Summary

SingleClientConnManager(HttpParams params, SchemeRegistry schreg)
Creates a new simple connection manager.

Method Summary

protected void	assertStillUp() Asserts that this manager is not shut down.
void	closeExpiredConnections() Closes all expired connections in the pool.
void	closeIdleConnections(long idletime, TimeUnit tunit) Closes idle connections in the pool.
protected ClientConnectionOperator	createConnectionOperator(SchemeRegistry schreg) Hook for creating the connection operator.
protected void	finalize()
ManagedClientConnection	getConnection(HttpRoute route, Object state) Obtains a connection.
SchemeRegistry	getSchemeRegistry() Obtains the scheme registry used by this manager.
void	releaseConnection(ManagedClientConnection conn, long validDuration, TimeUnit timeUnit) Releases a connection for use by others.
ClientConnectionRequest	requestConnection(HttpRoute route, Object state) Returns a new ClientConnectionRequest, from which a ManagedClientConnection can be obtained or the request can be aborted.
protected void	revokeConnection() Deprecated. no longer used
void	shutdown() Shuts down this connection manager and releases allocated resources.

Methods inherited from class java.lang.Object

clone, equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

MISUSE_MESSAGE

public static final String MISUSE_MESSAGE

The message to be logged on multiple allocation.

See Also:

Constant Field Values

schemeRegistry

protected final SchemeRegistry schemeRegistry

The schemes supported by this connection manager.

connOperator

protected final ClientConnectionOperator connOperator

The operator for opening and updating connections.

alwaysShutDown

protected final boolean alwaysShutDown

Whether the connection should be shut down on release.

uniquePoolEntry

@GuardedBy(value="this")
protected SingleClientConnManager.PoolEntry uniquePoolEntry

The one and only entry in this pool.

managedConn

@GuardedBy(value="this")
protected SingleClientConnManager.ConnAdapter managedConn

The currently issued managed connection, if any.

lastReleaseTime

@GuardedBy(value="this")
protected long lastReleaseTime

The time of the last connection release, or -1.

connectionExpiresTime

@GuardedBy(value="this")
protected long connectionExpiresTime

The time the last released connection expires and shouldn't be reused.

isShutDown

protected volatile boolean isShutDown

Indicates whether this connection manager is shut down.

Constructor Detail

SingleClientConnManager

public SingleClientConnManager(HttpParams params,
                               SchemeRegistry schreg)

Creates a new simple connection manager.

Parameters:

params - the parameters for this manager

schreg - the scheme registry, or null for the default registry

Method Detail

finalize

protected void finalize()
                 throws Throwable

Overrides:

finalize in class Object

Throws:

Throwable

getSchemeRegistry

public SchemeRegistry getSchemeRegistry()

Description copied from interface: ClientConnectionManager

Obtains the scheme registry used by this manager.

Specified by:

getSchemeRegistry in interface ClientConnectionManager

Returns:

the scheme registry, never null

createConnectionOperator

protected ClientConnectionOperator createConnectionOperator(SchemeRegistry schreg)

Hook for creating the connection operator. It is called by the constructor. Derived classes can override this method to change the instantiation of the operator. The default implementation here instantiates DefaultClientConnectionOperator.

Parameters:

schreg - the scheme registry to use, or null

Returns:

the connection operator to use

assertStillUp

protected final void assertStillUp()
                            throws IllegalStateException

Asserts that this manager is not shut down.

Throws:

IllegalStateException - if this manager is shut down

requestConnection

public final ClientConnectionRequest requestConnection(HttpRoute route,
                                                       Object state)

Description copied from interface: ClientConnectionManager

Returns a new ClientConnectionRequest, from which a ManagedClientConnection can be obtained or the request can be aborted.

Specified by:

requestConnection in interface ClientConnectionManager

getConnection

public ManagedClientConnection getConnection(HttpRoute route,
                                             Object state)

Obtains a connection.

Parameters:

route - where the connection should point to

Returns:

a connection that can be used to communicate along the given route

releaseConnection

public void releaseConnection(ManagedClientConnection conn,
                              long validDuration,
                              TimeUnit timeUnit)

Description copied from interface: ClientConnectionManager

Releases a connection for use by others. You may optionally specify how long the connection is valid to be reused. Values <= 0 are considered to be valid forever. If the connection is not marked as reusable, the connection will not be reused regardless of the valid duration. If the connection has been released before, the call will be ignored.

Specified by:

releaseConnection in interface ClientConnectionManager

Parameters:

conn - the connection to release

validDuration - the duration of time this connection is valid for reuse

timeUnit - the unit of time validDuration is measured in

See Also:

ClientConnectionManager.closeExpiredConnections()

closeExpiredConnections

public void closeExpiredConnections()

Description copied from interface: ClientConnectionManager

Closes all expired connections in the pool. Open connections in the pool that have not been used for the timespan defined when the connection was released will be closed. Currently allocated connections are not subject to this method. Times will be checked with milliseconds precision.

Specified by:

closeExpiredConnections in interface ClientConnectionManager

closeIdleConnections

public void closeIdleConnections(long idletime,
                                 TimeUnit tunit)

Description copied from interface: ClientConnectionManager

Closes idle connections in the pool. Open connections in the pool that have not been used for the timespan given by the argument will be closed. Currently allocated connections are not subject to this method. Times will be checked with milliseconds precision All expired connections will also be closed.

Specified by:

closeIdleConnections in interface ClientConnectionManager

Parameters:

idletime - the idle time of connections to be closed

tunit - the unit for the idletime

See Also:

ClientConnectionManager.closeExpiredConnections()

shutdown

public void shutdown()

Description copied from interface: ClientConnectionManager

Shuts down this connection manager and releases allocated resources. This includes closing all connections, whether they are currently used or not.

Specified by:

shutdown in interface ClientConnectionManager

revokeConnection

@Deprecated
protected void revokeConnection()

Deprecated. no longer used