public abstract class

AbstractClientConnAdapter

extends Object
implements ManagedClientConnection
java.lang.Object
   ↳ org.apache.http.impl.conn.AbstractClientConnAdapter
Known Direct Subclasses
Known Indirect Subclasses

Class Overview

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.

Summary

Protected Constructors
AbstractClientConnAdapter(ClientConnectionManager mgr, OperatedClientConnection conn)
Creates a new connection adapter.
Public Methods
void abortConnection()
Releases the connection without the option of keep-alive.
void flush()
Writes out all pending buffered data over the open connection.
InetAddress getLocalAddress()
int getLocalPort()
HttpConnectionMetrics getMetrics()
Returns a collection of connection metrcis
InetAddress getRemoteAddress()
int getRemotePort()
SSLSession getSSLSession()
Obtains the SSL session of the underlying connection, if any.
int getSocketTimeout()
Returns the socket timeout value.
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.
Protected Methods
final void assertNotAborted()
Asserts that the connection has not been aborted.
final void assertValid(OperatedClientConnection wrappedConn)
Asserts that there is a wrapped connection to delegate to.
void detach()
Detaches this adapter from the wrapped connection.
ClientConnectionManager getManager()
OperatedClientConnection getWrappedConnection()
[Expand]
Inherited Methods
From class java.lang.Object
From interface org.apache.http.HttpClientConnection
From interface org.apache.http.HttpConnection
From interface org.apache.http.HttpInetConnection
From interface org.apache.http.conn.ConnectionReleaseTrigger
From interface org.apache.http.conn.ManagedClientConnection

Protected Constructors

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

Public Methods

public void abortConnection ()

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.

public void flush ()

Writes out all pending buffered data over the open connection.

Throws
IOException

public InetAddress getLocalAddress ()

public int getLocalPort ()

public HttpConnectionMetrics getMetrics ()

Returns a collection of connection metrcis

Returns
  • HttpConnectionMetrics

public InetAddress getRemoteAddress ()

public int getRemotePort ()

public SSLSession getSSLSession ()

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 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.

Returns
  • the underlying SSL session if available, null otherwise

public int getSocketTimeout ()

Returns the socket timeout value.

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

public boolean isMarkedReusable ()

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

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

public boolean isOpen ()

Checks if this connection is open.

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

public boolean isResponseAvailable (int timeout)

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.

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

public boolean isSecure ()

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.

Returns
  • true if this connection is secure, false otherwise

public boolean isStale ()

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.

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

public void markReusable ()

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.

public void receiveResponseEntity (HttpResponse response)

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

Parameters
response the response to attach the entity to
Throws
HttpException
IOException

public HttpResponse receiveResponseHeader ()

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.

Returns
  • a new HttpResponse object with status line and headers initialized.
Throws
HttpException
IOException

public void releaseConnection ()

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.

public void sendRequestEntity (HttpEntityEnclosingRequest request)

Sends the request entity over the connection.

Parameters
request the request whose entity to send.
Throws
HttpException
IOException

public void sendRequestHeader (HttpRequest request)

Sends the request line and all headers over the connection.

Parameters
request the request whose headers to send.
Throws
HttpException
IOException

public void setIdleDuration (long duration, TimeUnit unit)

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.

public void setSocketTimeout (int timeout)

Sets the socket timeout value.

Parameters
timeout timeout value in milliseconds

public void unmarkReusable ()

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.

Protected Methods

protected final void assertNotAborted ()

Asserts that the connection has not been aborted.

Throws
InterruptedIOException if the connection has been aborted

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

protected void detach ()

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

protected ClientConnectionManager getManager ()

protected OperatedClientConnection getWrappedConnection ()