oracle.ide.net

Class MultiThreadURLFileSystemHelper

java.lang.Object

oracle.ide.net.URLFileSystemHelper

oracle.ide.net.MultiThreadURLFileSystemHelper

public class MultiThreadURLFileSystemHelper
extends URLFileSystemHelper

A convenience superclass that provide help for support nonblocking io on java.io operations

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	MultiThreadURLFileSystemHelper.InterruptibleClosure<R,C extends java.net.URLConnection> A closure for performing network operation in a context that they can be interrupted.

Constructor Summary

Constructors

Constructor and Description
MultiThreadURLFileSystemHelper()

Method Summary

Methods

Modifier and Type	Method and Description
protected void	closeConnection(java.net.URLConnection connection) Close a URLConnection.
<R,C extends java.net.URLConnection> R	invokeInterruptibly(java.net.URL url, MultiThreadURLFileSystemHelper.InterruptibleClosure<R,C> callable) This method allows client to invoke IO bound operations in a way that is still Interruptible unlike standard stream IO.
protected <T> T	invokeInterruptiblyNoThrowIO(java.net.URL url, MultiThreadURLFileSystemHelper.InterruptibleClosure<T,?> callable, T defaultValue) Internal convenienice version of the above method that eats the IOException and just returns a default value.
protected java.net.URLConnection	openConnection(java.net.URL url) Open a URLConnection.
protected java.io.InputStream	openInterruptibleInputStream(java.net.URL url)

Methods inherited from class oracle.ide.net.URLFileSystemHelper

addURLFileSystemListener, appendRelativePath, areEqual, areEqualPathElems, canCreate, canDelete, canonicalize, canRead, canWrite, code, convertSuffix, createReader, createTempFile, delete, ensureSuffix, equals, exists, getBaseParent, getDefaultIcon, getFileName, getLength, getName, getParent, getPath, getPathNoExt, getPlatformPathName, getPort, getSuffix, getSystemDisplayName, getSystemIcon, getTempDirectory, hashCode, hasSuffix, haveSameAuthority, haveSameHost, haveSamePath, haveSamePort, haveSameProtocol, haveSameQuery, haveSameRef, haveSameUserInfo, isBaseURLFor, isDirectory, isDirectoryPath, isHidden, isLocal, isReadOnly, isRegularFile, isValid, lastModified, list, list, list, listRoots, ls, ls, lsCached, lsCached, mkdir, mkdirs, openInputStream, openOutputStream, removeURLFileSystemListener, rename, setLastModified, setReadOnly, toDisplayString, toEncodedString, toEncodedString, toRelativeSpec, toRelativeSpec, verifyList

Methods inherited from class java.lang.Object

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

Constructor Detail

MultiThreadURLFileSystemHelper

public MultiThreadURLFileSystemHelper()

Method Detail

openConnection

protected java.net.URLConnection openConnection(java.net.URL url)
                                         throws java.io.IOException

Open a URLConnection.

Parameters:

url -

Returns:

the open connection

Throws:

java.io.IOException

closeConnection

protected void closeConnection(java.net.URLConnection connection)
                        throws java.io.IOException

Close a URLConnection.

Parameters:

connection -

Throws:

java.io.IOException

invokeInterruptibly

public <R,C extends java.net.URLConnection> R invokeInterruptibly(java.net.URL url,
                                                         MultiThreadURLFileSystemHelper.InterruptibleClosure<R,C> callable)
                      throws java.io.IOException

This method allows client to invoke IO bound operations in a way that is still Interruptible unlike standard stream IO. With standard IO the close will not react to a interrupt until either the connection times out or the connection is closed. this can result in deadlocks caused by background threads being trapped an unable to release locks on nodes.

The closure run in a thread pool so the latency of this operation should be low; but the code in the closure should be careful not to take any locks or require any locks to prevent deadlocks elsewhere.

The type of the connection is specified by the second type parameter on the closure, this is so that the enclosing code can close any open sockets in order to bring the enclosed code to an early end. At the moment the only connection type supported is URLConnection in the future when there is a more standard HttpClient support by the JDK, in 8, then we should probably support this also.

Type Parameters:

R - The value we are interested in

C - The value we are interested in

Parameters:

callable - The callable to be performed on the event queue

url - The URL we want to work on

Returns:

The result of the callable of a runtime exception should it be interrupted

Throws:

java.io.IOException

invokeInterruptiblyNoThrowIO

protected <T> T invokeInterruptiblyNoThrowIO(java.net.URL url,
                                 MultiThreadURLFileSystemHelper.InterruptibleClosure<T,?> callable,
                                 T defaultValue)

Internal convenienice version of the above method that eats the IOException and just returns a default value.

Type Parameters:

T - The value we are interested in

Parameters:

callable - The callable to be performed on the event queue

url - The URL to create the connection to

Returns:

The result of the callable of a runtime exception should it be interrupted

openInterruptibleInputStream

protected java.io.InputStream openInterruptibleInputStream(java.net.URL url)
                                                    throws java.io.IOException

Parameters:

url - The create the input stream for.

Returns:

An Interruptible input stream.

Throws:

java.io.IOException