public final class ServerContext extends Object
ServerContextclass contains static methods to execute some action within an appropriate server context for the current thread and to obtain the server context for the current thread.
|Modifier and Type||Class and Description|
Defines the interface for server context providers, which are consulted by
|Modifier and Type||Method and Description|
Sets the server context for the current thread to the supplied
Returns the server context collection for the current thread.
Returns the first element in the current server context collection (obtained by calling
public static void doWithServerContext(Runnable runnable, Collection context)
contextcollection and invokes the
runmethod of the supplied
runnableobject. When this method returns, the thread's server context is unset.
If a server context is currently set for the current thread,
that server context cannot be reset; that is, a server context
cannot be overwritten or nested. If a server context is already
set for the current thread, an
public static Collection getServerContext() throws ServerNotActiveException
ServerContext.doWithServerContext, then an ordered list of providers (obtained as specified below) implementing the
ServerContext.Spiinterface is consulted.
ServerContext.Spi.getServerContext()is called on each provider in turn; the first non-
nullreturn value is returned by this method. If no provider is able to supply a server context collection, then a
The list of server context providers is obtained as follows. For
each resource named
that is visible to the system class loader, the contents of the
resource are parsed as UTF-8 text to produce a list of class names.
The resource must contain a list of fully-qualified class names, one per
line. Space and tab characters surrounding each name, as well as blank
lines, are ignored. The comment character is '#'; all
characters on each line starting with the first comment character are
ignored. Each class name (that is not a duplicate of any previous class
name) is loaded through the system class loader, and the resulting
class must be assignable to
ServerContext.Spi and have a public
no-argument constructor. The constructor is invoked to create a fallback
context provider instance. An implementation is permitted to search for
provider instances eagerly (i.e., upon startup), and cache the
verifier instances rather than recreating them on every call.
The contents of the collection are determined by the caller of
context information available from a given element of the collection
is determined by that element's type. Examples of types that a
given element might implement include
The order of the elements in the collection is insignificant. The collection may be empty.
The caller of this method cannot assume that the returned collection is modifiable.
ServerNotActiveException- if no context is set for the current thread
public static Object getServerContextElement(Class type) throws ServerNotActiveException
ServerContext.getServerContext) that is an instance of the given type
type. If no element in the collection is an instance of the type
type- the type of the element
ServerNotActiveException- if no server context is set for the current thread
Copyright 2007-2013, multiple authors.
Licensed under the Apache License, Version 2.0, see the NOTICE file for attributions.