org.mozilla.javascript
Class Context

java.lang.Object
  org.mozilla.javascript.Context

public class Context
extends java.lang.Object

This class represents the runtime context of an executing script. Before executing a script, an instance of Context must be created and associated with the thread that will be executing the script. The Context will be used to store information about the executing of the script such as the call stack. Contexts are associated with the current thread using the call(ContextAction) or enter() methods.

Different forms of script execution are supported. Scripts may be evaluated from the source directly, or first compiled and then later executed. Interactive execution is also supported.

Some aspects of script execution, such as type conversions and object creation, may be accessed directly through methods of Context.

Author:

Norris Boyd, Brendan Eich

See Also:

Scriptable

Field Summary

static java.lang.Object[]	emptyArgs Convenient value to use as zero-length array of objects.
static java.lang.String	errorReporterProperty
static int	FEATURE_DYNAMIC_SCOPE Control if dynamic scope should be used for name access.
static int	FEATURE_E4X Control if support for E4X(ECMAScript for XML) extension is available.
static int	FEATURE_ENHANCED_JAVA_ACCESS Enables enhanced access to Java.
static int	FEATURE_LOCATION_INFORMATION_IN_ERROR When the feature is on Rhino will add a "fileName" and "lineNumber" properties to Error objects automatically.
static int	FEATURE_MEMBER_EXPR_AS_FUNCTION_NAME Control if member expression as function name extension is available.
static int	FEATURE_NON_ECMA_GET_YEAR Controls behaviour of Date.prototype.getYear().
static int	FEATURE_PARENT_PROTO_PROPERTIES Control if properties __proto__ and __parent__ are treated specially.
static int	FEATURE_PARENT_PROTO_PROPRTIES Deprecated. In previous releases, this name was given to FEATURE_PARENT_PROTO_PROPERTIES.
static int	FEATURE_RESERVED_KEYWORD_AS_IDENTIFIER Control if reserved keywords are treated as identifiers.
static int	FEATURE_STRICT_EVAL Control if strict eval mode is enabled.
static int	FEATURE_STRICT_MODE Controls whether JS 1.5 'strict mode' is enabled.
static int	FEATURE_STRICT_VARS Control if strict variable mode is enabled.
static int	FEATURE_TO_STRING_AS_SOURCE Control if toString() should returns the same result as toSource() when applied to objects and arrays.
static int	FEATURE_WARNING_AS_ERROR Controls whether a warning should be treated as an error.
boolean	generateObserverCount
static java.lang.String	languageVersionProperty
static int	VERSION_1_0 JavaScript 1.0
static int	VERSION_1_1 JavaScript 1.1
static int	VERSION_1_2 JavaScript 1.2
static int	VERSION_1_3 JavaScript 1.3
static int	VERSION_1_4 JavaScript 1.4
static int	VERSION_1_5 JavaScript 1.5
static int	VERSION_1_6 JavaScript 1.6
static int	VERSION_1_7 JavaScript 1.7
static int	VERSION_DEFAULT The default version.
static int	VERSION_UNKNOWN The unknown version.

Constructor Summary

Context()
Deprecated. use ContextFactory.enter() or ContextFactory.call(ContextAction) instead.

Method Summary

void	addActivationName(java.lang.String name) Add a name to the list of names forcing the creation of real activation objects for functions.
static void	addContextListener(org.mozilla.javascript.ContextListener listener) Deprecated.
void	addPropertyChangeListener(java.beans.PropertyChangeListener l) Register an object to receive notifications when a bound property has changed
static java.lang.Object	call(ContextAction action) Deprecated. use ContextFactory.call(ContextAction) instead as this method relies on usage of a static singleton "global" ContextFactory.
static java.lang.Object	call(ContextFactory factory, Callable callable, Scriptable scope, Scriptable thisObj, java.lang.Object[] args) Call Callable.call(Context cx, Scriptable scope, Scriptable thisObj, Object[] args) using the Context instance associated with the current thread.
static void	checkLanguageVersion(int version)
static void	checkOptimizationLevel(int optimizationLevel)
Function	compileFunction(Scriptable scope, java.lang.String source, java.lang.String sourceName, int lineno, java.lang.Object securityDomain) Compile a JavaScript function.
Script	compileReader(java.io.Reader in, java.lang.String sourceName, int lineno, java.lang.Object securityDomain) Compiles the source in the given reader.
Script	compileReader(Scriptable scope, java.io.Reader in, java.lang.String sourceName, int lineno, java.lang.Object securityDomain) Deprecated.
Script	compileString(java.lang.String source, java.lang.String sourceName, int lineno, java.lang.Object securityDomain) Compiles the source in the given string.
GeneratedClassLoader	createClassLoader(java.lang.ClassLoader parent) Create class loader for generated classes.
java.lang.String	decompileFunction(Function fun, int indent) Decompile a JavaScript Function.
java.lang.String	decompileFunctionBody(Function fun, int indent) Decompile the body of a JavaScript Function.
java.lang.String	decompileScript(Script script, int indent) Decompile the script.
static Context	enter() Deprecated. use ContextFactory.enter() or ContextFactory.call(ContextAction) instead as this method relies on usage of a static singleton "global" ContextFactory.
static Context	enter(Context cx) Deprecated. use ContextFactory.enterContext(Context) instead as this method relies on usage of a static singleton "global" ContextFactory.
java.lang.Object	evaluateReader(Scriptable scope, java.io.Reader in, java.lang.String sourceName, int lineno, java.lang.Object securityDomain) Evaluate a reader as JavaScript source.
java.lang.Object	evaluateString(Scriptable scope, java.lang.String source, java.lang.String sourceName, int lineno, java.lang.Object securityDomain) Evaluate a JavaScript source string.
static void	exit() Exit a block of code requiring a Context.
java.lang.ClassLoader	getApplicationClassLoader()
static Context	getCurrentContext() Get the current Context.
static DebuggableScript	getDebuggableView(Script script) Return DebuggableScript instance if any associated with the script.
org.mozilla.javascript.debug.Debugger	getDebugger() Return the current debugger.
java.lang.Object	getDebuggerContextData() Return the debugger context data associated with current context.
org.mozilla.javascript.xml.XMLLib.Factory	getE4xImplementationFactory() Returns an object which specifies an E4X implementation to use within this Context.
java.lang.Object[]	getElements(Scriptable object) Get the elements of a JavaScript array.
ErrorReporter	getErrorReporter() Get the current error reporter.
ContextFactory	getFactory() Return ContextFactory instance used to create this Context.
java.lang.String	getImplementationVersion() Get the implementation version.
int	getInstructionObserverThreshold() Get threshold of executed instructions counter that triggers call to observeInstructionCount().
int	getLanguageVersion() Get the current language version.
java.util.Locale	getLocale() Get the current locale.
int	getMaximumInterpreterStackDepth() Returns the maximum stack depth (in terms of number of call frames) allowed in a single invocation of interpreter.
int	getOptimizationLevel() Get the current optimization level.
java.lang.Object	getThreadLocal(java.lang.Object key) Get a value corresponding to a key.
static java.lang.Object	getUndefinedValue() Get the singleton object that represents the JavaScript Undefined value.
WrapFactory	getWrapFactory() Return the current WrapFactory, or null if none is defined.
boolean	hasCompileFunctionsWithDynamicScope() Deprecated.
boolean	hasFeature(int featureIndex) Controls certain aspects of script semantics.
ScriptableObject	initStandardObjects() Initialize the standard objects.
Scriptable	initStandardObjects(ScriptableObject scope) Initialize the standard objects.
ScriptableObject	initStandardObjects(ScriptableObject scope, boolean sealed) Initialize the standard objects.
boolean	isActivationNeeded(java.lang.String name) Check whether the name is in the list of names of objects forcing the creation of activation objects.
boolean	isGeneratingDebug() Tell whether debug information is being generated.
boolean	isGeneratingDebugChanged()
boolean	isGeneratingSource() Tell whether source information is being generated.
boolean	isSealed() Checks if this is a sealed Context.
static boolean	isValidLanguageVersion(int version)
static boolean	isValidOptimizationLevel(int optimizationLevel)
static java.lang.Object	javaToJS(java.lang.Object value, Scriptable scope) Convenient method to convert java value to its closest representation in JavaScript.
static java.lang.Object	jsToJava(java.lang.Object value, java.lang.Class desiredType) Convert a JavaScript value into the desired type.
Scriptable	newArray(Scriptable scope, int length) Create an array with a specified initial length.
Scriptable	newArray(Scriptable scope, java.lang.Object[] elements) Create an array with a set of initial elements.
Scriptable	newObject(Scriptable scope) Create a new JavaScript object.
Scriptable	newObject(Scriptable scope, java.lang.String constructorName) Create a new JavaScript object by executing the named constructor.
Scriptable	newObject(Scriptable scope, java.lang.String constructorName, java.lang.Object[] args) Creates a new JavaScript object by executing the named constructor.
protected void	observeInstructionCount(int instructionCount) Allow application to monitor counter of executed script instructions in Context subclasses.
void	putThreadLocal(java.lang.Object key, java.lang.Object value) Put a value that can later be retrieved using a given key.
void	removeActivationName(java.lang.String name) Remove a name from the list of names forcing the creation of real activation objects for functions.
static void	removeContextListener(org.mozilla.javascript.ContextListener listener) Deprecated.
void	removePropertyChangeListener(java.beans.PropertyChangeListener l) Remove an object from the list of objects registered to receive notification of changes to a bounded property
void	removeThreadLocal(java.lang.Object key) Remove values from thread-local storage.
static void	reportError(java.lang.String message) Report an error using the error reporter for the current thread.
static void	reportError(java.lang.String message, java.lang.String sourceName, int lineno, java.lang.String lineSource, int lineOffset) Report an error using the error reporter for the current thread.
static EvaluatorException	reportRuntimeError(java.lang.String message) Report a runtime error using the error reporter for the current thread.
static EvaluatorException	reportRuntimeError(java.lang.String message, java.lang.String sourceName, int lineno, java.lang.String lineSource, int lineOffset) Report a runtime error using the error reporter for the current thread.
static void	reportWarning(java.lang.String message) Report a warning using the error reporter for the current thread.
static void	reportWarning(java.lang.String message, java.lang.String sourceName, int lineno, java.lang.String lineSource, int lineOffset) Report a warning using the error reporter for the current thread.
static void	reportWarning(java.lang.String message, java.lang.Throwable t)
void	seal(java.lang.Object sealKey) Seal this Context object so any attempt to modify any of its properties including calling enter() and exit() methods will throw an exception.
void	setApplicationClassLoader(java.lang.ClassLoader loader)
static void	setCachingEnabled(boolean cachingEnabled) Deprecated.
void	setClassShutter(ClassShutter shutter) Set the LiveConnect access filter for this context.
void	setCompileFunctionsWithDynamicScope(boolean flag) Deprecated.
void	setDebugger(org.mozilla.javascript.debug.Debugger debugger, java.lang.Object contextData) Set the associated debugger.
ErrorReporter	setErrorReporter(ErrorReporter reporter) Change the current error reporter.
void	setGenerateObserverCount(boolean generateObserverCount) Turn on or off generation of code with callbacks to track the count of executed instructions.
void	setGeneratingDebug(boolean generatingDebug) Specify whether or not debug information should be generated.
void	setGeneratingSource(boolean generatingSource) Specify whether or not source information should be generated.
void	setInstructionObserverThreshold(int threshold) Set threshold of executed instructions counter that triggers call to observeInstructionCount().
void	setLanguageVersion(int version) Set the language version.
java.util.Locale	setLocale(java.util.Locale loc) Set the current locale.
void	setMaximumInterpreterStackDepth(int max) Sets the maximum stack depth (in terms of number of call frames) allowed in a single invocation of interpreter.
void	setOptimizationLevel(int optimizationLevel) Set the current optimization level.
void	setSecurityController(SecurityController controller) Set the security controller for this context.
void	setWrapFactory(WrapFactory wrapFactory) Set a WrapFactory for this Context.
boolean	stringIsCompilableUnit(java.lang.String source) Check whether a string is ready to be compiled.
static java.lang.RuntimeException	throwAsScriptRuntimeEx(java.lang.Throwable e) Rethrow the exception wrapping it as the script runtime exception.
static boolean	toBoolean(java.lang.Object value) Convert the value to a JavaScript boolean value.
static double	toNumber(java.lang.Object value) Convert the value to a JavaScript Number value.
static Scriptable	toObject(java.lang.Object value, Scriptable scope) Convert the value to an JavaScript object value.
static Scriptable	toObject(java.lang.Object value, Scriptable scope, java.lang.Class staticType) Deprecated.
static java.lang.String	toString(java.lang.Object value) Convert the value to a JavaScript String value.
static java.lang.Object	toType(java.lang.Object value, java.lang.Class desiredType) Deprecated.
void	unseal(java.lang.Object sealKey) Unseal previously sealed Context object.

Methods inherited from class java.lang.Object

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

Field Detail

VERSION_UNKNOWN

public static final int VERSION_UNKNOWN

The unknown version.

See Also:

Constant Field Values

VERSION_DEFAULT

public static final int VERSION_DEFAULT

The default version.

See Also:

Constant Field Values

VERSION_1_0

public static final int VERSION_1_0

JavaScript 1.0

See Also:

Constant Field Values

VERSION_1_1

public static final int VERSION_1_1

JavaScript 1.1

See Also:

Constant Field Values

VERSION_1_2

public static final int VERSION_1_2

JavaScript 1.2

See Also:

Constant Field Values

VERSION_1_3

public static final int VERSION_1_3

JavaScript 1.3

See Also:

Constant Field Values

VERSION_1_4

public static final int VERSION_1_4

JavaScript 1.4

See Also:

Constant Field Values

VERSION_1_5

public static final int VERSION_1_5

JavaScript 1.5

See Also:

Constant Field Values

VERSION_1_6

public static final int VERSION_1_6

JavaScript 1.6

See Also:

Constant Field Values

VERSION_1_7

public static final int VERSION_1_7

JavaScript 1.7

See Also:

Constant Field Values

FEATURE_NON_ECMA_GET_YEAR

public static final int FEATURE_NON_ECMA_GET_YEAR

Controls behaviour of Date.prototype.getYear(). If hasFeature(FEATURE_NON_ECMA_GET_YEAR) returns true, Date.prototype.getYear subtructs 1900 only if 1900 <= date < 2000. The default behavior of hasFeature(int) is always to subtruct 1900 as rquired by ECMAScript B.2.4.

See Also:

Constant Field Values

FEATURE_MEMBER_EXPR_AS_FUNCTION_NAME

public static final int FEATURE_MEMBER_EXPR_AS_FUNCTION_NAME

Control if member expression as function name extension is available. If hasFeature(FEATURE_MEMBER_EXPR_AS_FUNCTION_NAME) returns true, allow function memberExpression(args) { body } to be syntax sugar for memberExpression = function(args) { body }, when memberExpression is not a simple identifier. See ECMAScript-262, section 11.2 for definition of memberExpression. By default hasFeature(int) returns false.

See Also:

Constant Field Values

FEATURE_RESERVED_KEYWORD_AS_IDENTIFIER

public static final int FEATURE_RESERVED_KEYWORD_AS_IDENTIFIER

Control if reserved keywords are treated as identifiers. If hasFeature(RESERVED_KEYWORD_AS_IDENTIFIER) returns true, treat future reserved keyword (see Ecma-262, section 7.5.3) as ordinary identifiers but warn about this usage. By default hasFeature(int) returns false.

See Also:

Constant Field Values

FEATURE_TO_STRING_AS_SOURCE

public static final int FEATURE_TO_STRING_AS_SOURCE

Control if toString() should returns the same result as toSource() when applied to objects and arrays. If hasFeature(FEATURE_TO_STRING_AS_SOURCE) returns true, calling toString() on JS objects gives the same result as calling toSource(). That is it returns JS source with code to create an object with all enumeratable fields of the original object instead of printing [object result of Scriptable.getClassName()].

By default hasFeature(int) returns true only if the current JS version is set to VERSION_1_2.

See Also:

Constant Field Values

FEATURE_PARENT_PROTO_PROPERTIES

public static final int FEATURE_PARENT_PROTO_PROPERTIES

Control if properties __proto__ and __parent__ are treated specially. If hasFeature(FEATURE_PARENT_PROTO_PROPERTIES) returns true, treat __parent__ and __proto__ as special properties.

The properties allow to query and set scope and prototype chains for the objects. The special meaning of the properties is available only when they are used as the right hand side of the dot operator. For example, while x.__proto__ = y changes the prototype chain of the object x to point to y, x["__proto__"] = y simply assigns a new value to the property __proto__ in x even when the feature is on. By default hasFeature(int) returns true.

See Also:

Constant Field Values

FEATURE_PARENT_PROTO_PROPRTIES

public static final int FEATURE_PARENT_PROTO_PROPRTIES

Deprecated. In previous releases, this name was given to FEATURE_PARENT_PROTO_PROPERTIES.

See Also:

Constant Field Values

FEATURE_E4X

public static final int FEATURE_E4X

Control if support for E4X(ECMAScript for XML) extension is available. If hasFeature(FEATURE_E4X) returns true, the XML syntax is available.

By default hasFeature(int) returns true if the current JS version is set to VERSION_DEFAULT or is at least VERSION_1_6.

Since:

1.6 Release 1

See Also:

Constant Field Values

FEATURE_DYNAMIC_SCOPE

public static final int FEATURE_DYNAMIC_SCOPE

Control if dynamic scope should be used for name access. If hasFeature(FEATURE_DYNAMIC_SCOPE) returns true, then the name lookup during name resolution will use the top scope of the script or function which is at the top of JS execution stack instead of the top scope of the script or function from the current stack frame if the top scope of the top stack frame contains the top scope of the current stack frame on its prototype chain.

This is useful to define shared scope containing functions that can be called from scripts and functions using private scopes.

By default hasFeature(int) returns false.

Since:

1.6 Release 1

See Also:

Constant Field Values

FEATURE_STRICT_VARS

public static final int FEATURE_STRICT_VARS

Control if strict variable mode is enabled. When the feature is on Rhino reports runtime errors if assignment to a global variable that does not exist is executed. When the feature is off such assignments creates new variable in the global scope as required by ECMA 262.

By default hasFeature(int) returns false.

Since:

1.6 Release 1

See Also:

Constant Field Values

FEATURE_STRICT_EVAL

public static final int FEATURE_STRICT_EVAL

Control if strict eval mode is enabled. When the feature is on Rhino reports runtime errors if non-string argument is passed to the eval function. When the feature is off eval simply return non-string argument as is without performing any evaluation as required by ECMA 262.

By default hasFeature(int) returns false.

Since:

1.6 Release 1

See Also:

Constant Field Values

FEATURE_LOCATION_INFORMATION_IN_ERROR

public static final int FEATURE_LOCATION_INFORMATION_IN_ERROR

When the feature is on Rhino will add a "fileName" and "lineNumber" properties to Error objects automatically. When the feature is off, you have to explicitly pass them as the second and third argument to the Error constructor. Note that neither behaviour is fully ECMA 262 compliant (as 262 doesn't specify a three-arg constructor), but keeping the feature off results in Error objects that don't have additional non-ECMA properties when constructed using the ECMA-defined single-arg constructor and is thus desirable if a stricter ECMA compliance is desired, specifically adherence to the point 15.11.5. of the standard.

By default hasFeature(int) returns false.

Since:

1.6 Release 6

See Also:

Constant Field Values

FEATURE_STRICT_MODE

public static final int FEATURE_STRICT_MODE

Controls whether JS 1.5 'strict mode' is enabled. When the feature is on, Rhino reports more than a dozen different warnings. When the feature is off, these warnings are not generated. FEATURE_STRICT_MODE implies FEATURE_STRICT_VARS and FEATURE_STRICT_EVAL.

By default hasFeature(int) returns false.

Since:

1.6 Release 6

See Also:

Constant Field Values

FEATURE_WARNING_AS_ERROR

public static final int FEATURE_WARNING_AS_ERROR

Controls whether a warning should be treated as an error.

Since:

1.6 Release 6

See Also:

Constant Field Values

FEATURE_ENHANCED_JAVA_ACCESS

public static final int FEATURE_ENHANCED_JAVA_ACCESS

Enables enhanced access to Java. Specifically, controls whether private and protected members can be accessed, and whether scripts can catch all Java exceptions.

Note that this feature should only be enabled for trusted scripts.

By default hasFeature(int) returns false.

Since:

1.7 Release 1

See Also:

Constant Field Values

languageVersionProperty

public static final java.lang.String languageVersionProperty

See Also:

Constant Field Values

errorReporterProperty

public static final java.lang.String errorReporterProperty

See Also:

Constant Field Values

emptyArgs

public static final java.lang.Object[] emptyArgs

Convenient value to use as zero-length array of objects.

generateObserverCount

public boolean generateObserverCount

Constructor Detail

Context

public Context()

Deprecated. use ContextFactory.enter() or ContextFactory.call(ContextAction) instead.

Create a new Context. Note that the Context must be associated with a thread before it can be used to execute a script.

Method Detail

getCurrentContext

public static Context getCurrentContext()

Get the current Context. The current Context is per-thread; this method looks up the Context associated with the current thread.

Returns:

the Context associated with the current thread, or null if no context is associated with the current thread.

See Also:

ContextFactory.enterContext(), ContextFactory.call(ContextAction)

enter

public static Context enter()

Deprecated. use ContextFactory.enter() or ContextFactory.call(ContextAction) instead as this method relies on usage of a static singleton "global" ContextFactory.

Same as calling ContextFactory.enterContext() on the global ContextFactory instance.

Returns:

a Context associated with the current thread

See Also:

getCurrentContext(), exit(), call(ContextAction)

enter

public static Context enter(Context cx)

Deprecated. use ContextFactory.enterContext(Context) instead as this method relies on usage of a static singleton "global" ContextFactory.

Get a Context associated with the current thread, using the given Context if need be.

The same as enter() except that cx is associated with the current thread and returned if the current thread has no associated context and cx is not associated with any other thread.

Parameters:

cx - a Context to associate with the thread if possible

Returns:

a Context associated with the current thread

See Also:

ContextFactory.enterContext(Context), ContextFactory.call(ContextAction)

exit

public static void exit()

Exit a block of code requiring a Context. Calling exit() will remove the association between the current thread and a Context if the prior call to ContextFactory.enterContext() on this thread newly associated a Context with this thread. Once the current thread no longer has an associated Context, it cannot be used to execute JavaScript until it is again associated with a Context.

See Also:

ContextFactory.enterContext()

call

public static java.lang.Object call(ContextAction action)

Deprecated. use ContextFactory.call(ContextAction) instead as this method relies on usage of a static singleton "global" ContextFactory.

Call ContextAction.run(Context cx) using the Context instance associated with the current thread. If no Context is associated with the thread, then ContextFactory.getGlobal().makeContext() will be called to construct new Context instance. The instance will be temporary associated with the thread during call to ContextAction.run(Context).

Returns:

The result of ContextAction.run(Context).

call

public static java.lang.Object call(ContextFactory factory,
                                    Callable callable,
                                    Scriptable scope,
                                    Scriptable thisObj,
                                    java.lang.Object[] args)

Call Callable.call(Context cx, Scriptable scope, Scriptable thisObj, Object[] args) using the Context instance associated with the current thread. If no Context is associated with the thread, then ContextFactory.makeContext() will be called to construct new Context instance. The instance will be temporary associated with the thread during call to ContextAction.run(Context).

It is allowed but not advisable to use null for factory argument in which case the global static singleton ContextFactory instance will be used to create new context instances.

See Also:

ContextFactory.call(ContextAction)

addContextListener

public static void addContextListener(org.mozilla.javascript.ContextListener listener)

Deprecated.

See Also:

ContextFactory.addListener(ContextFactory.Listener), ContextFactory.getGlobal()

removeContextListener

public static void removeContextListener(org.mozilla.javascript.ContextListener listener)

Deprecated.

See Also:

ContextFactory.removeListener(ContextFactory.Listener), ContextFactory.getGlobal()

getFactory

public final ContextFactory getFactory()

Return ContextFactory instance used to create this Context.

isSealed

public final boolean isSealed()

Checks if this is a sealed Context. A sealed Context instance does not allow to modify any of its properties and will throw an exception on any such attempt.

See Also:

seal(Object sealKey)

seal

public final void seal(java.lang.Object sealKey)

Seal this Context object so any attempt to modify any of its properties including calling enter() and exit() methods will throw an exception.

If sealKey is not null, calling unseal(Object sealKey) with the same key unseals the object. If sealKey is null, unsealing is no longer possible.

See Also:

isSealed(), unseal(Object)

unseal

public final void unseal(java.lang.Object sealKey)

Unseal previously sealed Context object. The sealKey argument should not be null and should match sealKey suplied with the last call to seal(Object) or an exception will be thrown.

See Also:

isSealed(), seal(Object sealKey)

getLanguageVersion

public final int getLanguageVersion()

Get the current language version.

The language version number affects JavaScript semantics as detailed in the overview documentation.

Returns:

an integer that is one of VERSION_1_0, VERSION_1_1, etc.

setLanguageVersion

public void setLanguageVersion(int version)

Set the language version.

Setting the language version will affect functions and scripts compiled subsequently. See the overview documentation for version-specific behavior.

Parameters:

version - the version as specified by VERSION_1_0, VERSION_1_1, etc.

isValidLanguageVersion

public static boolean isValidLanguageVersion(int version)

checkLanguageVersion

public static void checkLanguageVersion(int version)

getImplementationVersion

public final java.lang.String getImplementationVersion()

Get the implementation version.

The implementation version is of the form

    "name langVer release relNum date"
 

where name is the name of the product, langVer is the language version, relNum is the release number, and date is the release date for that specific release in the form "yyyy mm dd".

Returns:

a string that encodes the product, language version, release number, and date.

getErrorReporter

public final ErrorReporter getErrorReporter()

Get the current error reporter.

See Also:

ErrorReporter

setErrorReporter

public final ErrorReporter setErrorReporter(ErrorReporter reporter)

Change the current error reporter.

Returns:

the previous error reporter

See Also:

ErrorReporter

getLocale

public final java.util.Locale getLocale()

Get the current locale. Returns the default locale if none has been set.

See Also:

Locale

setLocale

public final java.util.Locale setLocale(java.util.Locale loc)

Set the current locale.

See Also:

Locale

addPropertyChangeListener

public final void addPropertyChangeListener(java.beans.PropertyChangeListener l)

Register an object to receive notifications when a bound property has changed

Parameters:

l - the listener

See Also:

PropertyChangeEvent, removePropertyChangeListener(java.beans.PropertyChangeListener)

removePropertyChangeListener

public final void removePropertyChangeListener(java.beans.PropertyChangeListener l)

Remove an object from the list of objects registered to receive notification of changes to a bounded property

Parameters:

l - the listener

See Also:

PropertyChangeEvent, addPropertyChangeListener(java.beans.PropertyChangeListener)

reportWarning

public static void reportWarning(java.lang.String message,
                                 java.lang.String sourceName,
                                 int lineno,
                                 java.lang.String lineSource,
                                 int lineOffset)

Report a warning using the error reporter for the current thread.

Parameters:

message - the warning message to report

sourceName - a string describing the source, such as a filename

lineno - the starting line number

lineSource - the text of the line (may be null)

lineOffset - the offset into lineSource where problem was detected

See Also:

ErrorReporter

reportWarning

public static void reportWarning(java.lang.String message)

Report a warning using the error reporter for the current thread.

Parameters:

message - the warning message to report

See Also:

ErrorReporter

reportWarning

public static void reportWarning(java.lang.String message,
                                 java.lang.Throwable t)

reportError

public static void reportError(java.lang.String message,
                               java.lang.String sourceName,
                               int lineno,
                               java.lang.String lineSource,
                               int lineOffset)

Report an error using the error reporter for the current thread.

Parameters:

message - the error message to report

sourceName - a string describing the source, such as a filename

lineno - the starting line number

lineSource - the text of the line (may be null)

lineOffset - the offset into lineSource where problem was detected

See Also:

ErrorReporter

reportError

public static void reportError(java.lang.String message)

Report an error using the error reporter for the current thread.

Parameters:

message - the error message to report

See Also:

ErrorReporter

reportRuntimeError

public static EvaluatorException reportRuntimeError(java.lang.String message,
                                                    java.lang.String sourceName,
                                                    int lineno,
                                                    java.lang.String lineSource,
                                                    int lineOffset)

Report a runtime error using the error reporter for the current thread.

Parameters:

message - the error message to report

sourceName - a string describing the source, such as a filename

lineno - the starting line number

lineSource - the text of the line (may be null)

lineOffset - the offset into lineSource where problem was detected

Returns:

a runtime exception that will be thrown to terminate the execution of the script

See Also:

ErrorReporter

reportRuntimeError

public static EvaluatorException reportRuntimeError(java.lang.String message)

Report a runtime error using the error reporter for the current thread.

Parameters:

message - the error message to report

See Also:

ErrorReporter

initStandardObjects

public final ScriptableObject initStandardObjects()

Initialize the standard objects. Creates instances of the standard objects and their constructors (Object, String, Number, Date, etc.), setting up 'scope' to act as a global object as in ECMA 15.1.

This method must be called to initialize a scope before scripts can be evaluated in that scope.

This method does not affect the Context it is called upon.

Returns:

the initialized scope

initStandardObjects

public final Scriptable initStandardObjects(ScriptableObject scope)

Initialize the standard objects. Creates instances of the standard objects and their constructors (Object, String, Number, Date, etc.), setting up 'scope' to act as a global object as in ECMA 15.1.

This method must be called to initialize a scope before scripts can be evaluated in that scope.

This method does not affect the Context it is called upon.

Parameters:

scope - the scope to initialize, or null, in which case a new object will be created to serve as the scope

Returns:

the initialized scope. The method returns the value of the scope argument if it is not null or newly allocated scope object which is an instance ScriptableObject.

initStandardObjects

public ScriptableObject initStandardObjects(ScriptableObject scope,
                                            boolean sealed)

Initialize the standard objects. Creates instances of the standard objects and their constructors (Object, String, Number, Date, etc.), setting up 'scope' to act as a global object as in ECMA 15.1.

This method must be called to initialize a scope before scripts can be evaluated in that scope.

This method does not affect the Context it is called upon.

This form of the method also allows for creating "sealed" standard objects. An object that is sealed cannot have properties added, changed, or removed. This is useful to create a "superglobal" that can be shared among several top-level objects. Note that sealing is not allowed in the current ECMA/ISO language specification, but is likely for the next version.

Parameters:

scope - the scope to initialize, or null, in which case a new object will be created to serve as the scope

sealed - whether or not to create sealed standard objects that cannot be modified.

Returns:

the initialized scope. The method returns the value of the scope argument if it is not null or newly allocated scope object.

Since:

1.4R3

getUndefinedValue

public static java.lang.Object getUndefinedValue()

Get the singleton object that represents the JavaScript Undefined value.

evaluateString

public final java.lang.Object evaluateString(Scriptable scope,
                                             java.lang.String source,
                                             java.lang.String sourceName,
                                             int lineno,
                                             java.lang.Object securityDomain)

Evaluate a JavaScript source string. The provided source name and line number are used for error messages and for producing debug information.

Parameters:

scope - the scope to execute in

source - the JavaScript source

sourceName - a string describing the source, such as a filename

lineno - the starting line number

securityDomain - an arbitrary object that specifies security information about the origin or owner of the script. For implementations that don't care about security, this value may be null.

Returns:

the result of evaluating the string

See Also:

SecurityController

evaluateReader

public final java.lang.Object evaluateReader(Scriptable scope,
                                             java.io.Reader in,
                                             java.lang.String sourceName,
                                             int lineno,
                                             java.lang.Object securityDomain)
                                      throws java.io.IOException

Evaluate a reader as JavaScript source. All characters of the reader are consumed.

Parameters:

scope - the scope to execute in

in - the Reader to get JavaScript source from

sourceName - a string describing the source, such as a filename

lineno - the starting line number

securityDomain - an arbitrary object that specifies security information about the origin or owner of the script. For implementations that don't care about security, this value may be null.

Returns:

the result of evaluating the source

Throws:

java.io.IOException - if an IOException was generated by the Reader

stringIsCompilableUnit

public final boolean stringIsCompilableUnit(java.lang.String source)

Check whether a string is ready to be compiled.

stringIsCompilableUnit is intended to support interactive compilation of javascript. If compiling the string would result in an error that might be fixed by appending more source, this method returns false. In every other case, it returns true.

Interactive shells may accumulate source lines, using this method after each new line is appended to check whether the statement being entered is complete.

Parameters:

source - the source buffer to check

Returns:

whether the source is ready for compilation

Since:

1.4 Release 2

compileReader

public final Script compileReader(Scriptable scope,
                                  java.io.Reader in,
                                  java.lang.String sourceName,
                                  int lineno,
                                  java.lang.Object securityDomain)
                           throws java.io.IOException

Deprecated.

Throws:

java.io.IOException

See Also:

compileReader(Reader in, String sourceName, int lineno, Object securityDomain)

compileReader

public final Script compileReader(java.io.Reader in,
                                  java.lang.String sourceName,
                                  int lineno,
                                  java.lang.Object securityDomain)
                           throws java.io.IOException

Compiles the source in the given reader.

Returns a script that may later be executed. Will consume all the source in the reader.

Parameters:

in - the input reader

sourceName - a string describing the source, such as a filename

lineno - the starting line number for reporting errors

securityDomain - an arbitrary object that specifies security information about the origin or owner of the script. For implementations that don't care about security, this value may be null.

Returns:

a script that may later be executed

Throws:

java.io.IOException - if an IOException was generated by the Reader

See Also:

Script

compileString

public final Script compileString(java.lang.String source,
                                  java.lang.String sourceName,
                                  int lineno,
                                  java.lang.Object securityDomain)

Compiles the source in the given string.

Returns a script that may later be executed.

Parameters:

source - the source string

sourceName - a string describing the source, such as a filename

lineno - the starting line number for reporting errors

securityDomain - an arbitrary object that specifies security information about the origin or owner of the script. For implementations that don't care about security, this value may be null.

Returns:

a script that may later be executed

See Also:

Script

compileFunction

public final Function compileFunction(Scriptable scope,
                                      java.lang.String source,
                                      java.lang.String sourceName,
                                      int lineno,
                                      java.lang.Object securityDomain)

Compile a JavaScript function.

The function source must be a function definition as defined by ECMA (e.g., "function f(a) { return a; }").

Parameters:

scope - the scope to compile relative to

source - the function definition source

sourceName - a string describing the source, such as a filename

lineno - the starting line number

securityDomain - an arbitrary object that specifies security information about the origin or owner of the script. For implementations that don't care about security, this value may be null.

Returns:

a Function that may later be called

See Also:

Function

decompileScript

public final java.lang.String decompileScript(Script script,
                                              int indent)

Decompile the script.

The canonical source of the script is returned.

Parameters:

script - the script to decompile

indent - the number of spaces to indent the result

Returns:

a string representing the script source

decompileFunction

public final java.lang.String decompileFunction(Function fun,
                                                int indent)

Decompile a JavaScript Function.

Decompiles a previously compiled JavaScript function object to canonical source.

Returns function body of '[native code]' if no decompilation information is available.

Parameters:

fun - the JavaScript function to decompile

indent - the number of spaces to indent the result

Returns:

a string representing the function source

decompileFunctionBody

public final java.lang.String decompileFunctionBody(Function fun,
                                                    int indent)

Decompile the body of a JavaScript Function.

Decompiles the body a previously compiled JavaScript Function object to canonical source, omitting the function header and trailing brace. Returns '[native code]' if no decompilation information is available.

Parameters:

fun - the JavaScript function to decompile

indent - the number of spaces to indent the result

Returns:

a string representing the function body source.

newObject

public final Scriptable newObject(Scriptable scope)

Create a new JavaScript object. Equivalent to evaluating "new Object()".

Parameters:

scope - the scope to search for the constructor and to evaluate against

Returns:

the new object

newObject

public final Scriptable newObject(Scriptable scope,
                                  java.lang.String constructorName)

Create a new JavaScript object by executing the named constructor. The call newObject(scope, "Foo") is equivalent to evaluating "new Foo()".

Parameters:

scope - the scope to search for the constructor and to evaluate against

constructorName - the name of the constructor to call

Returns:

the new object

newObject

public final Scriptable newObject(Scriptable scope,
                                  java.lang.String constructorName,
                                  java.lang.Object[] args)

Creates a new JavaScript object by executing the named constructor. Searches scope for the named constructor, calls it with the given arguments, and returns the result.

The code

 Object[] args = { "a", "b" };
 newObject(scope, "Foo", args)

is equivalent to evaluating "new Foo('a', 'b')", assuming that the Foo constructor has been defined in scope.

Parameters:

scope - The scope to search for the constructor and to evaluate against

constructorName - the name of the constructor to call

args - the array of arguments for the constructor

Returns:

the new object

newArray

public final Scriptable newArray(Scriptable scope,
                                 int length)

Create an array with a specified initial length.

Parameters:

scope - the scope to create the object in

length - the initial length (JavaScript arrays may have additional properties added dynamically).

Returns:

the new array object

newArray

public final Scriptable newArray(Scriptable scope,
                                 java.lang.Object[] elements)

Create an array with a set of initial elements.

Parameters:

scope - the scope to create the object in.

elements - the initial elements. Each object in this array must be an acceptable JavaScript type and type of array should be exactly Object[], not SomeObjectSubclass[].

Returns:

the new array object.

getElements

public final java.lang.Object[] getElements(Scriptable object)

Get the elements of a JavaScript array.

If the object defines a length property convertible to double number, then the number is converted Uint32 value as defined in Ecma 9.6 and Java array of that size is allocated. The array is initialized with the values obtained by calling get() on object for each value of i in [0,length-1]. If there is not a defined value for a property the Undefined value is used to initialize the corresponding element in the array. The Java array is then returned. If the object doesn't define a length property or it is not a number, empty array is returned.

Parameters:

object - the JavaScript array or array-like object

Returns:

a Java array of objects

Since:

1.4 release 2

toBoolean

public static boolean toBoolean(java.lang.Object value)

Convert the value to a JavaScript boolean value.

See ECMA 9.2.

Parameters:

value - a JavaScript value

Returns:

the corresponding boolean value converted using the ECMA rules

toNumber

public static double toNumber(java.lang.Object value)

Convert the value to a JavaScript Number value.

Returns a Java double for the JavaScript Number.

See ECMA 9.3.

Parameters:

value - a JavaScript value

Returns:

the corresponding double value converted using the ECMA rules

toString

public static java.lang.String toString(java.lang.Object value)

Convert the value to a JavaScript String value.

See ECMA 9.8.

Parameters:

value - a JavaScript value

Returns:

the corresponding String value converted using the ECMA rules

toObject

public static Scriptable toObject(java.lang.Object value,
                                  Scriptable scope)

Convert the value to an JavaScript object value.

Note that a scope must be provided to look up the constructors for Number, Boolean, and String.

See ECMA 9.9.

Additionally, arbitrary Java objects and classes will be wrapped in a Scriptable object with its Java fields and methods reflected as JavaScript properties of the object.

Parameters:

value - any Java object

scope - global scope containing constructors for Number, Boolean, and String

Returns:

new JavaScript object

toObject

public static Scriptable toObject(java.lang.Object value,
                                  Scriptable scope,
                                  java.lang.Class staticType)

Deprecated.

See Also:

toObject(Object, Scriptable)

javaToJS

public static java.lang.Object javaToJS(java.lang.Object value,
                                        Scriptable scope)

Convenient method to convert java value to its closest representation in JavaScript.

If value is an instance of String, Number, Boolean, Function or Scriptable, it is returned as it and will be treated as the corresponding JavaScript type of string, number, boolean, function and object.

Note that for Number instances during any arithmetic operation in JavaScript the engine will always use the result of Number.doubleValue() resulting in a precision loss if the number can not fit into double.

If value is an instance of Character, it will be converted to string of length 1 and its JavaScript type will be string.

The rest of values will be wrapped as LiveConnect objects by calling WrapFactory.wrap(Context cx, Scriptable scope, Object obj, Class staticType) as in:

    Context cx = Context.getCurrentContext();
    return cx.getWrapFactory().wrap(cx, scope, value, null);
 

Parameters:

value - any Java object

scope - top scope object

Returns:

value suitable to pass to any API that takes JavaScript values.

jsToJava

public static java.lang.Object jsToJava(java.lang.Object value,
                                        java.lang.Class desiredType)
                                 throws EvaluatorException

Convert a JavaScript value into the desired type. Uses the semantics defined with LiveConnect3 and throws an Illegal argument exception if the conversion cannot be performed.

Parameters:

value - the JavaScript value to convert

desiredType - the Java type to convert to. Primitive Java types are represented using the TYPE fields in the corresponding wrapper class in java.lang.

Returns:

the converted value

Throws:

EvaluatorException - if the conversion cannot be performed

toType

public static java.lang.Object toType(java.lang.Object value,
                                      java.lang.Class desiredType)
                               throws java.lang.IllegalArgumentException

Deprecated.

Throws:

java.lang.IllegalArgumentException - if the conversion cannot be performed. Note that jsToJava(Object, Class) throws EvaluatorException instead.

See Also:

jsToJava(Object, Class)

throwAsScriptRuntimeEx

public static java.lang.RuntimeException throwAsScriptRuntimeEx(java.lang.Throwable e)

Rethrow the exception wrapping it as the script runtime exception. Unless the exception is instance of EcmaError or EvaluatorException it will be wrapped as WrappedException, a subclass of EvaluatorException. The resulting exception object always contains source name and line number of script that triggered exception.

This method always throws an exception, its return value is provided only for convenience to allow a usage like:

 throw Context.throwAsScriptRuntimeEx(ex);
 

to indicate that code after the method is unreachable.

Throws:

EvaluatorException

EcmaError

isGeneratingDebug

public final boolean isGeneratingDebug()

Tell whether debug information is being generated.

Since:

1.3

setGeneratingDebug

public final void setGeneratingDebug(boolean generatingDebug)

Specify whether or not debug information should be generated.

Setting the generation of debug information on will set the optimization level to zero.

Since:

1.3

isGeneratingSource

public final boolean isGeneratingSource()

Tell whether source information is being generated.

Since:

1.3

setGeneratingSource

public final void setGeneratingSource(boolean generatingSource)

Specify whether or not source information should be generated.

Without source information, evaluating the "toString" method on JavaScript functions produces only "[native code]" for the body of the function. Note that code generated without source is not fully ECMA conformant.

Since:

1.3

getOptimizationLevel

public final int getOptimizationLevel()

Get the current optimization level.

The optimization level is expressed as an integer between -1 and 9.

Since:

1.3

setOptimizationLevel

public final void setOptimizationLevel(int optimizationLevel)

Set the current optimization level.

The optimization level is expected to be an integer between -1 and 9. Any negative values will be interpreted as -1, and any values greater than 9 will be interpreted as 9. An optimization level of -1 indicates that interpretive mode will always be used. Levels 0 through 9 indicate that class files may be generated. Higher optimization levels trade off compile time performance for runtime performance. The optimizer level can't be set greater than -1 if the optimizer package doesn't exist at run time.

Parameters:

optimizationLevel - an integer indicating the level of optimization to perform

Since:

1.3

isValidOptimizationLevel

public static boolean isValidOptimizationLevel(int optimizationLevel)

checkOptimizationLevel

public static void checkOptimizationLevel(int optimizationLevel)

getMaximumInterpreterStackDepth

public final int getMaximumInterpreterStackDepth()

Returns the maximum stack depth (in terms of number of call frames) allowed in a single invocation of interpreter. If the set depth would be exceeded, the interpreter will throw an EvaluatorException in the script. Defaults to Integer.MAX_VALUE. The setting only has effect for interpreted functions (those compiled with optimization level set to -1). As the interpreter doesn't use the Java stack but rather manages its own stack in the heap memory, a runaway recursion in interpreted code would eventually consume all available memory and cause OutOfMemoryError instead of a StackOverflowError limited to only a single thread. This setting helps prevent such situations.

Returns:

The current maximum interpreter stack depth.

setMaximumInterpreterStackDepth

public final void setMaximumInterpreterStackDepth(int max)

Sets the maximum stack depth (in terms of number of call frames) allowed in a single invocation of interpreter. If the set depth would be exceeded, the interpreter will throw an EvaluatorException in the script. Defaults to Integer.MAX_VALUE. The setting only has effect for interpreted functions (those compiled with optimization level set to -1). As the interpreter doesn't use the Java stack but rather manages its own stack in the heap memory, a runaway recursion in interpreted code would eventually consume all available memory and cause OutOfMemoryError instead of a StackOverflowError limited to only a single thread. This setting helps prevent such situations.

Parameters:

max - the new maximum interpreter stack depth

Throws:

java.lang.IllegalStateException - if this context's optimization level is not -1

java.lang.IllegalArgumentException - if the new depth is not at least 1

setSecurityController

public final void setSecurityController(SecurityController controller)

Set the security controller for this context.

SecurityController may only be set if it is currently null and SecurityController.hasGlobal() is false. Otherwise a SecurityException is thrown.

Parameters:

controller - a SecurityController object

Throws:

java.lang.SecurityException - if there is already a SecurityController object for this Context or globally installed.

See Also:

SecurityController.initGlobal(SecurityController controller), SecurityController.hasGlobal()

setClassShutter

public final void setClassShutter(ClassShutter shutter)

Set the LiveConnect access filter for this context.

ClassShutter may only be set if it is currently null. Otherwise a SecurityException is thrown.

Parameters:

shutter - a ClassShutter object

Throws:

java.lang.SecurityException - if there is already a ClassShutter object for this Context

getThreadLocal

public final java.lang.Object getThreadLocal(java.lang.Object key)

Get a value corresponding to a key.

Since the Context is associated with a thread it can be used to maintain values that can be later retrieved using the current thread.

Note that the values are maintained with the Context, so if the Context is disassociated from the thread the values cannot be retrieved. Also, if private data is to be maintained in this manner the key should be a java.lang.Object whose reference is not divulged to untrusted code.

Parameters:

key - the key used to lookup the value

Returns:

a value previously stored using putThreadLocal.

putThreadLocal

public final void putThreadLocal(java.lang.Object key,
                                 java.lang.Object value)

Put a value that can later be retrieved using a given key.

Parameters:

key - the key used to index the value

value - the value to save

removeThreadLocal

public final void removeThreadLocal(java.lang.Object key)

Remove values from thread-local storage.

Parameters:

key - the key for the entry to remove.

Since:

1.5 release 2

hasCompileFunctionsWithDynamicScope

public final boolean hasCompileFunctionsWithDynamicScope()

Deprecated.

See Also:

FEATURE_DYNAMIC_SCOPE, hasFeature(int)

setCompileFunctionsWithDynamicScope

public final void setCompileFunctionsWithDynamicScope(boolean flag)

Deprecated.

See Also:

FEATURE_DYNAMIC_SCOPE, hasFeature(int)

setCachingEnabled

public static void setCachingEnabled(boolean cachingEnabled)

Deprecated.

See Also:

ClassCache.get(Scriptable), ClassCache.setCachingEnabled(boolean)

setWrapFactory

public final void setWrapFactory(WrapFactory wrapFactory)

Set a WrapFactory for this Context.

The WrapFactory allows custom object wrapping behavior for Java object manipulated with JavaScript.

Since:

1.5 Release 4

See Also:

WrapFactory

getWrapFactory

public final WrapFactory getWrapFactory()

Return the current WrapFactory, or null if none is defined.

Since:

1.5 Release 4

See Also:

WrapFactory

getDebugger

public final org.mozilla.javascript.debug.Debugger getDebugger()

Return the current debugger.

Returns:

the debugger, or null if none is attached.

getDebuggerContextData

public final java.lang.Object getDebuggerContextData()

Return the debugger context data associated with current context.

Returns:

the debugger data, or null if debugger is not attached

setDebugger

public final void setDebugger(org.mozilla.javascript.debug.Debugger debugger,
                              java.lang.Object contextData)

Set the associated debugger.

Parameters:

debugger - the debugger to be used on callbacks from the engine.

contextData - arbitrary object that debugger can use to store per Context data.

getDebuggableView

public static DebuggableScript getDebuggableView(Script script)

Return DebuggableScript instance if any associated with the script. If callable supports DebuggableScript implementation, the method returns it. Otherwise null is returned.

hasFeature

public boolean hasFeature(int featureIndex)

Controls certain aspects of script semantics. Should be overwritten to alter default behavior.

The default implementation calls ContextFactory.hasFeature(Context cx, int featureIndex) that allows to customize Context behavior without introducing Context subclasses. ContextFactory documentation gives an example of hasFeature implementation.

Parameters:

featureIndex - feature index to check

Returns:

true if the featureIndex feature is turned on

See Also:

FEATURE_NON_ECMA_GET_YEAR, FEATURE_MEMBER_EXPR_AS_FUNCTION_NAME, FEATURE_RESERVED_KEYWORD_AS_IDENTIFIER, FEATURE_TO_STRING_AS_SOURCE, FEATURE_PARENT_PROTO_PROPRTIES, FEATURE_E4X, FEATURE_DYNAMIC_SCOPE, FEATURE_STRICT_VARS, FEATURE_STRICT_EVAL, FEATURE_LOCATION_INFORMATION_IN_ERROR, FEATURE_STRICT_MODE, FEATURE_WARNING_AS_ERROR, FEATURE_ENHANCED_JAVA_ACCESS

getE4xImplementationFactory

public org.mozilla.javascript.xml.XMLLib.Factory getE4xImplementationFactory()

Returns an object which specifies an E4X implementation to use within this Context. Note that the XMLLib.Factory interface should be considered experimental. The default implementation uses the implementation provided by this Context's ContextFactory.

Returns:

An XMLLib.Factory. Should not return null if FEATURE_E4X is enabled. See hasFeature(int).

getInstructionObserverThreshold

public final int getInstructionObserverThreshold()

Get threshold of executed instructions counter that triggers call to observeInstructionCount(). When the threshold is zero, instruction counting is disabled, otherwise each time the run-time executes at least the threshold value of script instructions, observeInstructionCount() will be called.

setInstructionObserverThreshold

public final void setInstructionObserverThreshold(int threshold)

Set threshold of executed instructions counter that triggers call to observeInstructionCount(). When the threshold is zero, instruction counting is disabled, otherwise each time the run-time executes at least the threshold value of script instructions, observeInstructionCount() will be called.

Note that the meaning of "instruction" is not guaranteed to be consistent between compiled and interpretive modes: executing a given script or function in the different modes will result in different instruction counts against the threshold. setGenerateObserverCount(boolean) is called with true if threshold is greater than zero, false otherwise.

Parameters:

threshold - The instruction threshold

setGenerateObserverCount

public void setGenerateObserverCount(boolean generateObserverCount)

Turn on or off generation of code with callbacks to track the count of executed instructions. Currently only affects JVM byte code generation: this slows down the generated code, but code generated without the callbacks will not be counted toward instruction thresholds. Rhino's interpretive mode does instruction counting without inserting callbacks, so there is no requirement to compile code differently.

Parameters:

generateObserverCount - if true, generated code will contain calls to accumulate an estimate of the instructions executed.

observeInstructionCount

protected void observeInstructionCount(int instructionCount)

Allow application to monitor counter of executed script instructions in Context subclasses. Run-time calls this when instruction counting is enabled and the counter reaches limit set by setInstructionObserverThreshold(). The method is useful to observe long running scripts and if necessary to terminate them.

The instruction counting support is available only for interpreted scripts generated when the optimization level is set to -1.

The default implementation calls ContextFactory.observeInstructionCount(Context cx, int instructionCount) that allows to customize Context behavior without introducing Context subclasses.

Parameters:

instructionCount - amount of script instruction executed since last call to observeInstructionCount

Throws:

java.lang.Error - to terminate the script

See Also:

setOptimizationLevel(int)

createClassLoader

public GeneratedClassLoader createClassLoader(java.lang.ClassLoader parent)

Create class loader for generated classes. The method calls ContextFactory.createClassLoader(ClassLoader) using the result of getFactory().

getApplicationClassLoader

public final java.lang.ClassLoader getApplicationClassLoader()

setApplicationClassLoader

public final void setApplicationClassLoader(java.lang.ClassLoader loader)

isGeneratingDebugChanged

public final boolean isGeneratingDebugChanged()

addActivationName

public void addActivationName(java.lang.String name)

Add a name to the list of names forcing the creation of real activation objects for functions.

Parameters:

name - the name of the object to add to the list

isActivationNeeded

public final boolean isActivationNeeded(java.lang.String name)

Check whether the name is in the list of names of objects forcing the creation of activation objects.

Parameters:

name - the name of the object to test

Returns:

true if an function activation object is needed.

removeActivationName

public void removeActivationName(java.lang.String name)

Remove a name from the list of names forcing the creation of real activation objects for functions.

Parameters:

name - the name of the object to remove from the list