org.apache.http.impl.conn
Class AbstractClientConnAdapter

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

All Implemented Interfaces:

ConnectionReleaseTrigger, ManagedClientConnection, HttpClientConnection, HttpConnection, HttpInetConnection

Direct Known Subclasses:

AbstractPooledConnAdapter

public abstract class AbstractClientConnAdapter
extends Object
implements ManagedClientConnection

Abstract adapter from operated to managed client connections. Read and write methods are delegated to the wrapped connection. Operations affecting the connection state have to be implemented by derived classes. Operations for querying the connection state are delegated to the wrapped connection if there is one, or return a default value if there is none.
This adapter tracks the checkpoints for reusable communication states, as indicated by markReusable and queried by isMarkedReusable. All send and receive operations will automatically clear the mark.
Connection release calls are delegated to the connection manager, if there is one. abortConnection will clear the reusability mark first. The connection manager is expected to tolerate multiple calls to the release method.

Since:

4.0

Constructor Summary

protected

AbstractClientConnAdapter(ClientConnectionManager mgr, OperatedClientConnection conn) Creates a new connection adapter.

Method Summary

void	abortConnection() Releases the connection without the option of keep-alive.
protected void	assertNotAborted() Asserts that the connection has not been aborted.
protected void	assertValid(OperatedClientConnection wrappedConn) Asserts that there is a wrapped connection to delegate to.
protected void	detach() Detaches this adapter from the wrapped connection.
void	flush() Writes out all pending buffered data over the open connection.
InetAddress	getLocalAddress()
int	getLocalPort()
protected ClientConnectionManager	getManager()
HttpConnectionMetrics	getMetrics() Returns a collection of connection metrcis
InetAddress	getRemoteAddress()
int	getRemotePort()
int	getSocketTimeout() Returns the socket timeout value.
SSLSession	getSSLSession() Obtains the SSL session of the underlying connection, if any.
protected OperatedClientConnection	getWrappedConnection()
boolean	isMarkedReusable() Indicates whether this connection is in a reusable communication state.
boolean	isOpen() Checks if this connection is open.
boolean	isResponseAvailable(int timeout) Checks if response data is available from the connection.
boolean	isSecure() Indicates whether this connection is secure.
boolean	isStale() Checks whether this connection has gone down.
void	markReusable() Marks this connection as being in a reusable communication state.
void	receiveResponseEntity(HttpResponse response) Receives the next response entity available from this connection and attaches it to an existing HttpResponse object.
HttpResponse	receiveResponseHeader() Receives the request line and headers of the next response available from this connection.
void	releaseConnection() Releases the connection with the option of keep-alive.
void	sendRequestEntity(HttpEntityEnclosingRequest request) Sends the request entity over the connection.
void	sendRequestHeader(HttpRequest request) Sends the request line and all headers over the connection.
void	setIdleDuration(long duration, TimeUnit unit) Sets the duration that this connection can remain idle before it is reused.
void	setSocketTimeout(int timeout) Sets the socket timeout value.
void	unmarkReusable() Marks this connection as not being in a reusable state.

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.http.conn.ManagedClientConnection

getRoute, getState, layerProtocol, open, setState, tunnelProxy, tunnelTarget

Methods inherited from interface org.apache.http.HttpConnection

close, shutdown

Constructor Detail

AbstractClientConnAdapter

protected AbstractClientConnAdapter(ClientConnectionManager mgr,
                                    OperatedClientConnection conn)

Creates a new connection adapter. The adapter is initially not marked as reusable.

Parameters:

mgr - the connection manager, or null

conn - the connection to wrap, or null

Method Detail

detach

protected void detach()

Detaches this adapter from the wrapped connection. This adapter becomes useless.

getWrappedConnection

protected OperatedClientConnection getWrappedConnection()

getManager

protected ClientConnectionManager getManager()

assertNotAborted

protected final void assertNotAborted()
                               throws InterruptedIOException

Asserts that the connection has not been aborted.

Throws:

InterruptedIOException - if the connection has been aborted

assertValid

protected final void assertValid(OperatedClientConnection wrappedConn)

Asserts that there is a wrapped connection to delegate to.

Throws:

IllegalStateException - if there is no wrapped connection or connection has been aborted

isOpen

public boolean isOpen()

Description copied from interface: HttpConnection

Checks if this connection is open.

Specified by:

isOpen in interface HttpConnection

Returns:

true if it is open, false if it is closed.

isStale

public boolean isStale()

Description copied from interface: HttpConnection

Checks whether this connection has gone down. Network connections may get closed during some time of inactivity for several reasons. The next time a read is attempted on such a connection it will throw an IOException. This method tries to alleviate this inconvenience by trying to find out if a connection is still usable. Implementations may do that by attempting a read with a very small timeout. Thus this method may block for a small amount of time before returning a result. It is therefore an expensive operation.

Specified by:

isStale in interface HttpConnection

Returns:

true if attempts to use this connection are likely to succeed, or false if they are likely to fail and this connection should be closed

setSocketTimeout

public void setSocketTimeout(int timeout)

Description copied from interface: HttpConnection

Sets the socket timeout value.

Specified by:

setSocketTimeout in interface HttpConnection

Parameters:

timeout - timeout value in milliseconds

getSocketTimeout

public int getSocketTimeout()

Description copied from interface: HttpConnection

Returns the socket timeout value.

Specified by:

getSocketTimeout in interface HttpConnection

Returns:

positive value in milliseconds if a timeout is set, 0 if timeout is disabled or -1 if timeout is undefined.

getMetrics

public HttpConnectionMetrics getMetrics()

Description copied from interface: HttpConnection

Returns a collection of connection metrcis

Specified by:

getMetrics in interface HttpConnection

Returns:

HttpConnectionMetrics

flush

public void flush()
           throws IOException

Description copied from interface: HttpClientConnection

Writes out all pending buffered data over the open connection.

Specified by:

flush in interface HttpClientConnection

Throws:

IOException

isResponseAvailable

public boolean isResponseAvailable(int timeout)
                            throws IOException

Description copied from interface: HttpClientConnection

Checks if response data is available from the connection. May wait for the specified time until some data becomes available. Note that some implementations may completely ignore the timeout parameter.

Specified by:

isResponseAvailable in interface HttpClientConnection

Parameters:

timeout - the maximum time in milliseconds to wait for data

Returns:

true if data is available; false if there was no data available even after waiting for timeout milliseconds.

Throws:

IOException - if an error happens on the connection

receiveResponseEntity

public void receiveResponseEntity(HttpResponse response)
                           throws HttpException,
                                  IOException

Description copied from interface: HttpClientConnection

Receives the next response entity available from this connection and attaches it to an existing HttpResponse object.

Specified by:

receiveResponseEntity in interface HttpClientConnection

Parameters:

response - the response to attach the entity to

Throws:

HttpException

IOException

receiveResponseHeader

public HttpResponse receiveResponseHeader()
                                   throws HttpException,
                                          IOException

Description copied from interface: HttpClientConnection

Receives the request line and headers of the next response available from this connection. The caller should examine the HttpResponse object to find out if it should try to receive a response entity as well.

Specified by:

receiveResponseHeader in interface HttpClientConnection

Returns:

a new HttpResponse object with status line and headers initialized.

Throws:

HttpException

IOException

sendRequestEntity

public void sendRequestEntity(HttpEntityEnclosingRequest request)
                       throws HttpException,
                              IOException

Description copied from interface: HttpClientConnection

Sends the request entity over the connection.

Specified by:

sendRequestEntity in interface HttpClientConnection

Parameters:

request - the request whose entity to send.

Throws:

HttpException

IOException

sendRequestHeader

public void sendRequestHeader(HttpRequest request)
                       throws HttpException,
                              IOException

Description copied from interface: HttpClientConnection

Sends the request line and all headers over the connection.

Specified by:

sendRequestHeader in interface HttpClientConnection

Parameters:

request - the request whose headers to send.

Throws:

HttpException

IOException

getLocalAddress

public InetAddress getLocalAddress()

Specified by:

getLocalAddress in interface HttpInetConnection

getLocalPort

public int getLocalPort()

Specified by:

getLocalPort in interface HttpInetConnection

getRemoteAddress

public InetAddress getRemoteAddress()

Specified by:

getRemoteAddress in interface HttpInetConnection

getRemotePort

public int getRemotePort()

Specified by:

getRemotePort in interface HttpInetConnection

isSecure

public boolean isSecure()

Description copied from interface: ManagedClientConnection

Indicates whether this connection is secure. The return value is well-defined only while the connection is open. It may change even while the connection is open.

Specified by:

isSecure in interface ManagedClientConnection

Returns:

true if this connection is secure, false otherwise

getSSLSession

public SSLSession getSSLSession()

Description copied from interface: ManagedClientConnection

Obtains the SSL session of the underlying connection, if any. If this connection is open, and the underlying socket is an SSLSocket, the SSL session of that socket is obtained. This is a potentially blocking operation.
Note: Whether the underlying socket is an SSL socket can not necessarily be determined via ManagedClientConnection.isSecure(). Plain sockets may be considered secure, for example if they are connected to a known host in the same network segment. On the other hand, SSL sockets may be considered insecure, for example depending on the chosen cipher suite.

Specified by:

getSSLSession in interface ManagedClientConnection

Returns:

the underlying SSL session if available, null otherwise

markReusable

public void markReusable()

Description copied from interface: ManagedClientConnection

Marks this connection as being in a reusable communication state. The checkpoints for reuseable communication states (in the absence of pipelining) are before sending a request and after receiving the response in it's entirety. The connection will automatically clear the checkpoint when used for communication. A call to this method indicates that the next checkpoint has been reached.
A reusable communication state is necessary but not sufficient for the connection to be reused. A route mismatch, the connection being closed, or other circumstances might prevent reuse.

Specified by:

markReusable in interface ManagedClientConnection

unmarkReusable

public void unmarkReusable()

Description copied from interface: ManagedClientConnection

Marks this connection as not being in a reusable state. This can be used immediately before releasing this connection to prevent it's reuse. Reasons for preventing reuse include error conditions and the evaluation of a reuse strategy.
Note: It is not necessary to call here before writing to or reading from this connection. Communication attempts will automatically unmark the state as non-reusable. It can then be switched back using markReusable.

Specified by:

unmarkReusable in interface ManagedClientConnection

isMarkedReusable

public boolean isMarkedReusable()

Description copied from interface: ManagedClientConnection

Indicates whether this connection is in a reusable communication state. See markReusable and unmarkReusable for details.

Specified by:

isMarkedReusable in interface ManagedClientConnection

Returns:

true if this connection is marked as being in a reusable communication state, false otherwise

setIdleDuration

public void setIdleDuration(long duration,
                            TimeUnit unit)

Description copied from interface: ManagedClientConnection

Sets the duration that this connection can remain idle before it is reused. The connection should not be used again if this time elapses. The idle duration must be reset after each request sent over this connection. The elapsed time starts counting when the connection is released, which is typically after the headers (and any response body, if present) is fully consumed.

Specified by:

setIdleDuration in interface ManagedClientConnection

releaseConnection

public void releaseConnection()

Description copied from interface: ConnectionReleaseTrigger

Releases the connection with the option of keep-alive. This is a "graceful" release and may cause IO operations for consuming the remainder of a response entity. Use abortConnection for a hard release. The connection may be reused as specified by the duration.

Specified by:

releaseConnection in interface ConnectionReleaseTrigger

abortConnection

public void abortConnection()

Description copied from interface: ConnectionReleaseTrigger

Releases the connection without the option of keep-alive. This is a "hard" release that implies a shutdown of the connection. Use releaseConnection for a graceful release.

Specified by:

abortConnection in interface ConnectionReleaseTrigger