public class ScriptEngineManager extends Object
ScriptEngineManager
implements a discovery and instantiation
mechanism for ScriptEngine
classes and also maintains a
collection of key/value pairs storing state shared by all engines created
by the Manager. This class uses the service provider mechanism to enumerate all the
implementations of ScriptEngineFactory
. ScriptEngineManager
provides a method to return a list of all these factories
as well as utility methods which look up factories on the basis of language name, file extension
and mime type.
The Bindings
of key/value pairs, referred to as the "Global Scope" maintained
by the manager is available to all instances of ScriptEngine
created
by the ScriptEngineManager
. The values in the Bindings
are
generally exposed in all scripts.
Constructor and Description |
---|
ScriptEngineManager()
The effect of calling this constructor is the same as calling
ScriptEngineManager(Thread.currentThread().getContextClassLoader()) . |
ScriptEngineManager(ClassLoader loader)
This constructor loads the implementations of
ScriptEngineFactory visible to the given
ClassLoader using the service provider mechanism.If loader is null , the script engine factories that are
bundled with the platform and that are in the usual extension
directories (installed extensions) are loaded. |
Modifier and Type | Method and Description |
---|---|
Object |
get(String key)
Gets the value for the specified key in the Global Scope
|
Bindings |
getBindings()
getBindings returns the value of the globalScope field. |
ScriptEngine |
getEngineByExtension(String extension)
Look up and create a
ScriptEngine for a given extension. |
ScriptEngine |
getEngineByMimeType(String mimeType)
Look up and create a
ScriptEngine for a given mime type. |
ScriptEngine |
getEngineByName(String shortName)
Looks up and creates a
ScriptEngine for a given name. |
List<ScriptEngineFactory> |
getEngineFactories()
Returns a list whose elements are instances of all the
ScriptEngineFactory classes
found by the discovery mechanism. |
void |
put(String key,
Object value)
Sets the specified key/value pair in the Global Scope.
|
void |
registerEngineExtension(String extension,
ScriptEngineFactory factory)
Registers a
ScriptEngineFactory to handle an extension. |
void |
registerEngineMimeType(String type,
ScriptEngineFactory factory)
Registers a
ScriptEngineFactory to handle a mime type. |
void |
registerEngineName(String name,
ScriptEngineFactory factory)
Registers a
ScriptEngineFactory to handle a language
name. |
void |
setBindings(Bindings bindings)
setBindings stores the specified Bindings
in the globalScope field. |
public ScriptEngineManager()
ScriptEngineManager(Thread.currentThread().getContextClassLoader())
.Thread.getContextClassLoader()
public ScriptEngineManager(ClassLoader loader)
ScriptEngineFactory
visible to the given
ClassLoader
using the service provider mechanism.null
, the script engine factories that are
bundled with the platform and that are in the usual extension
directories (installed extensions) are loaded. loader
- ClassLoader used to discover script engine factories.public void setBindings(Bindings bindings)
setBindings
stores the specified Bindings
in the globalScope
field. ScriptEngineManager sets this
Bindings
as global bindings for ScriptEngine
objects created by it.bindings
- The specified Bindings
IllegalArgumentException
- if bindings is null.public Bindings getBindings()
getBindings
returns the value of the globalScope
field.
ScriptEngineManager sets this Bindings
as global bindings for
ScriptEngine
objects created by it.public void put(String key, Object value)
key
- Key to setvalue
- Value to set.NullPointerException
- if key is null.IllegalArgumentException
- if key is empty string.public Object get(String key)
key
- The key whose value is to be returned.public ScriptEngine getEngineByName(String shortName)
ScriptEngine
for a given name.
The algorithm first searches for a ScriptEngineFactory
that has been
registered as a handler for the specified name using the registerEngineName
method.
ScriptEngineFactory
instances
stored by the constructor for one with the specified name. If a ScriptEngineFactory
is found by either method, it is used to create instance of ScriptEngine
.shortName
- The short name of the ScriptEngine
implementation.
returned by the getNames
method of its ScriptEngineFactory
.ScriptEngine
created by the factory located in the search. Returns null
if no such factory was found. The ScriptEngineManager
sets its own globalScope
Bindings
as the GLOBAL_SCOPE
Bindings
of the newly
created ScriptEngine
.NullPointerException
- if shortName is null.public ScriptEngine getEngineByExtension(String extension)
ScriptEngine
for a given extension. The algorithm
used by getEngineByName
is used except that the search starts
by looking for a ScriptEngineFactory
registered to handle the
given extension using registerEngineExtension
.extension
- The given extensionnull
if not found.NullPointerException
- if extension is null.public ScriptEngine getEngineByMimeType(String mimeType)
ScriptEngine
for a given mime type. The algorithm
used by getEngineByName
is used except that the search starts
by looking for a ScriptEngineFactory
registered to handle the
given mime type using registerEngineMimeType
.mimeType
- The given mime typenull
if not found.NullPointerException
- if mimeType is null.public List<ScriptEngineFactory> getEngineFactories()
ScriptEngineFactory
classes
found by the discovery mechanism.ScriptEngineFactory
s.public void registerEngineName(String name, ScriptEngineFactory factory)
ScriptEngineFactory
to handle a language
name. Overrides any such association found using the Discovery mechanism.name
- The name to be associated with the ScriptEngineFactory
.factory
- The class to associate with the given name.NullPointerException
- if any of the parameters is null.public void registerEngineMimeType(String type, ScriptEngineFactory factory)
ScriptEngineFactory
to handle a mime type.
Overrides any such association found using the Discovery mechanism.type
- The mime type to be associated with the
ScriptEngineFactory
.factory
- The class to associate with the given mime type.NullPointerException
- if any of the parameters is null.public void registerEngineExtension(String extension, ScriptEngineFactory factory)
ScriptEngineFactory
to handle an extension.
Overrides any such association found using the Discovery mechanism.extension
- The extension type to be associated with the
ScriptEngineFactory
.factory
- The class to associate with the given extension.NullPointerException
- if any of the parameters is null. Submit a bug or feature
For further API reference and developer documentation, see Java SE Documentation. That documentation contains more detailed, developer-targeted descriptions, with conceptual overviews, definitions of terms, workarounds, and working code examples.
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