javax.script
Interface ScriptEngine

All Known Subinterfaces:

IPhpScriptEngine

All Known Implementing Classes:

AbstractScriptEngine, InteractivePhpScriptEngine, InvocablePhpScriptEngine, PhpScriptEngine

public interface ScriptEngine

The ScriptEngine interfaces contains only the methods which are expected to be fully functional in every Java ScriptEngine.

Author:

Nandika Jayawardana , Sanka Samaranayake

Field Summary

static java.lang.String	ARGV Reserved key associated with an object array which is used to pass set of positional parameters to the ScriptEngines.
static java.lang.String	ENGINE Reserved key associated with the name of the Java ScriptEngine
static java.lang.String	ENGINE_VERSION Reserved key associated with the version of the Java ScriptEngine
static java.lang.String	FILENAME Reserved key associated with name of the file which contains the source of the script.
static java.lang.String	LANGUAGE Reserved key associated with the name of the supported scripting language
static java.lang.String	LANGUAGE_VERSION Reserved key associated with the version of the supported scripting language
static java.lang.String	NAME Reserved key associated with the named value which identifies the short name of the supported language

Method Summary

Bindings	createBindings() Retrieves an uninitailized namespace which can be used as the scope of the ScriptEngine.
java.lang.Object	eval(java.io.Reader reader) Evaluates a piece of script obtained using the specified reader as the script source.
java.lang.Object	eval(java.io.Reader reader, Bindings namespace) Evaluates a piece of scripts obtained using a reader as the script source and using the specified namespace as the SCRIPT_SCOPE.
java.lang.Object	eval(java.io.Reader reader, ScriptContext context) Evaluates a script obtained using the specified reader as the script source and using the namespaces in the specifed ScriptContext.
java.lang.Object	eval(java.lang.String script) Evaluates a piece of script and returns the resultant object.
java.lang.Object	eval(java.lang.String script, Bindings namespace) Evaluates a piece of script using the specified namespace as the SCRIPT_SCOPE.
java.lang.Object	eval(java.lang.String script, ScriptContext context) Evaluates a script using the namespaces in the specifed ScriptContext.
java.lang.Object	get(java.lang.String key) Retrieves the value which is associated with the specified key in the state of the ScriptEngine.
Bindings	getBindings(int scope) Retrieves a reference to the associated namespace for the specified level of scope.
ScriptContext	getContext()
ScriptEngineFactory	getFactory() Retrieves a ScriptEngineFactory for the class to which describes the underlying ScriptEngine.
void	put(java.lang.String key, java.lang.Object value) Associates a key and a value in the ScriptEngine namespace.
void	setBindings(Bindings namespace, int scope) Associates the specified namespace with the specified level of scope.
void	setContext(ScriptContext ctx) Set the default ScriptContext

Field Detail

ARGV

static final java.lang.String ARGV

Reserved key associated with an object array which is used to pass set of positional parameters to the ScriptEngines.

See Also:

Constant Field Values

FILENAME

static final java.lang.String FILENAME

Reserved key associated with name of the file which contains the source of the script.

See Also:

Constant Field Values

ENGINE

static final java.lang.String ENGINE

Reserved key associated with the name of the Java ScriptEngine

See Also:

Constant Field Values

ENGINE_VERSION

static final java.lang.String ENGINE_VERSION

Reserved key associated with the version of the Java ScriptEngine

See Also:

Constant Field Values

LANGUAGE

static final java.lang.String LANGUAGE

Reserved key associated with the name of the supported scripting language

See Also:

Constant Field Values

LANGUAGE_VERSION

static final java.lang.String LANGUAGE_VERSION

Reserved key associated with the version of the supported scripting language

See Also:

Constant Field Values

NAME

static final java.lang.String NAME

Reserved key associated with the named value which identifies the short name of the supported language

See Also:

Constant Field Values

Method Detail

createBindings

Bindings createBindings()

Retrieves an uninitailized namespace which can be used as the scope of the ScriptEngine.

Returns:

an initialzed namespace which can be used to repalce the state of the ScriptEngine

eval

java.lang.Object eval(java.io.Reader reader)
                      throws ScriptException

Evaluates a piece of script obtained using the specified reader as the script source. Returns null for non-returning scripts.

Parameters:

reader - the source of the script

Returns:

the value of the evaluated script

Throws:

ScriptException - if an error occurs

eval

java.lang.Object eval(java.io.Reader reader,
                      Bindings namespace)
                      throws ScriptException

Evaluates a piece of scripts obtained using a reader as the script source and using the specified namespace as the SCRIPT_SCOPE. Returns null for non-returning scripts.

Parameters:

reader - the script source used to obtained the script

namespace - the namespace to be used as SCRIPT_SCOPE

Returns:

the value of the evaluated script

Throws:

ScriptException - if an error occurs

eval

java.lang.Object eval(java.io.Reader reader,
                      ScriptContext context)
                      throws ScriptException

Evaluates a script obtained using the specified reader as the script source and using the namespaces in the specifed ScriptContext. Returns null for non-returning scripts

Parameters:

reader - the script source

context - the context contianing different namespace for script evaluation

Returns:

the value of the evaluated script

Throws:

ScriptException - if an error occurs

eval

java.lang.Object eval(java.lang.String script)
                      throws ScriptException

Evaluates a piece of script and returns the resultant object. Returns null for non-returning scripts.

Parameters:

script - the String representation of the script

Returns:

the value of the evaluated script

Throws:

ScriptException - if an error occurs

eval

java.lang.Object eval(java.lang.String script,
                      Bindings namespace)
                      throws ScriptException

Evaluates a piece of script using the specified namespace as the SCRIPT_SCOPE. Retruns null for non-returning scripts.

Parameters:

script - the String representation of the script

namespace - the namespace to be used as the SCRIPT_SCOPE

Returns:

the value of the evaluated script

Throws:

ScriptException - if an error occurs

eval

java.lang.Object eval(java.lang.String script,
                      ScriptContext context)
                      throws ScriptException

Evaluates a script using the namespaces in the specifed ScriptContext. Return null for non-returning scripts.

Parameters:

script - the String representation of the script

context - tbe ScriptContext containing namespaces for the script evaluation

Returns:

the value of the evaluated script

Throws:

ScriptException - if an error occurs

get

java.lang.Object get(java.lang.String key)

Retrieves the value which is associated with the specified key in the state of the ScriptEngine.

Parameters:

key - the key associated with value.

Returns:

an object value which is associated with the key

getFactory

ScriptEngineFactory getFactory()

Retrieves a ScriptEngineFactory for the class to which describes the underlying ScriptEngine.

Returns:

an instance of ScriptEngineFactory which describes the underlying ScriptEngine

getBindings

Bindings getBindings(int scope)
                     throws java.lang.IllegalArgumentException

Retrieves a reference to the associated namespace for the specified level of scope. Possible scopes are: GLOBAL_SCOPE : if the ScriptEngine was created by ScriptingEngineManager then GLOBAL_SCOPE of it is returned (or null if there is no GLOBAL_SCOPE stored in the ScriptEngine). ENGINE_SCOPE : the set of key-value pairs stored in the ScriptEngine is returned.

Parameters:

scope - the specified level of scope

Returns:

associated namespace for the specified level of scope

Throws:

java.lang.IllegalArgumentException - if the scope is invalid

put

void put(java.lang.String key,
         java.lang.Object value)
         throws java.lang.IllegalArgumentException

Associates a key and a value in the ScriptEngine namespace.

Parameters:

key - the specified key associated with the value

value - value which is to be associated with the specified key

Throws:

java.lang.IllegalArgumentException - if the key is null

setBindings

void setBindings(Bindings namespace,
                 int scope)
                 throws java.lang.IllegalArgumentException

Associates the specified namespace with the specified level of scope.

Parameters:

namespace - namespace to be associated with the specified level of scope

scope - level of scope for which the namespace should be associated with

Throws:

java.lang.IllegalArgumentException - if the scope is invalid

getContext

ScriptContext getContext()

Returns:

the default ScriptContext.

setContext

void setContext(ScriptContext ctx)

Set the default ScriptContext

Parameters:

ctx - The context