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 enter() method.

The behavior of the execution engine may be altered through methods such as setErrorReporter.

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 Convinient value to use as zero-length argument array object.
static java.lang.String	errorReporterProperty
static int	FEATURE_MEMBER_EXPR_AS_FUNCTION_NAME 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 simply identifier.
static int	FEATURE_NON_ECMA_GET_YEAR If hasFeature(FEATURE_NON_ECMA_GET_YEAR) returns true, Date.prototype.getYear subtructs 1900 only if 1900 <= date < 2000.
static int	FEATURE_RESERVED_KEYWORD_AS_IDENTIFIER 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
static int	FEATURE_TO_STRING_AS_SOURCE If hasFeature(FEATURE_TO_STRING_AS_SOURCE) returns true, calling toString on JS objects gives JS source with code to create an object with all enumeratable fields of the original object instead of printing "[object ]".
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_DEFAULT The default version.
static int	VERSION_UNKNOWN The unknown version.

Constructor Summary

Context()
Create a new Context.

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(ContextListener listener) Add a Context listener.
void	addPropertyChangeListener(java.beans.PropertyChangeListener l) Register an object to receive notifications when a bound property has changed
static java.lang.Object	call(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.
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. The method implementation simply calls compileReader(Reader in, String sourceName, int lineno, Object securityDomain) ignoring scope argument.
Script	compileString(java.lang.String source, java.lang.String sourceName, int lineno, java.lang.Object securityDomain) Compiles the source in the given string.
org.mozilla.javascript.GeneratedClassLoader	createClassLoader(java.lang.ClassLoader parent)
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, Scriptable scope, int indent) Decompile the script.
static void	disableStaticContextListening() Disable notifications of listeners registered with addContextListener(ContextListener) about Context events.
static Context	enter() Get a context associated with the current thread, creating one if need be.
static Context	enter(Context cx) Get a Context associated with the current thread, using the given Context if need be.
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.
org.mozilla.javascript.debug.Debugger	getDebugger() Return the current debugger.
java.lang.Object	getDebuggerContextData() Return the debugger context data associated with current context.
java.lang.Object[]	getElements(Scriptable object) Get the elements of a JavaScript array.
ErrorReporter	getErrorReporter() Get the current error reporter.
java.lang.String	getImplementationVersion() Get the implementation version.
int	getInstructionObserverThreshold() Get/Set 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	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 WrapHandler, or null if none is defined.
org.mozilla.javascript.WrapHandler	getWrapHandler() Deprecated. As of Rhino 1.5 Release 4, use WrapFactory and getWrapFactory()
boolean	hasCompileFunctionsWithDynamicScope() Return whether functions are compiled by this context using dynamic scope.
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 java.lang.Object	javaToJS(java.lang.Object value, Scriptable scope) Convenient method to convert java value to its closest representation in JavaScript.
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.
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(ContextListener listener) Remove a Context listener.
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.
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. To enable/disable caching for a particular top scope, use ClassCache.get(Scriptable) and ClassCache.setCachingEnabled(boolean). The function is kept only for compatibility and does nothing.
void	setClassShutter(ClassShutter shutter) Set the LiveConnect access filter for this context.
void	setCompileFunctionsWithDynamicScope(boolean flag) Set whether functions compiled by this context should use dynamic scope.
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	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)
void	setLanguageVersion(int version) Set the language version.
java.util.Locale	setLocale(java.util.Locale loc) Set the current locale.
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.
void	setWrapHandler(org.mozilla.javascript.WrapHandler wrapHandler) Deprecated. As of Rhino 1.5 Release 4, use WrapFactory and setWrapFactory(WrapFactory)
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. Use toObject(Object, Scriptable) instead.
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) Convert a JavaScript value into the desired type.
void	unseal(java.lang.Object sealKey) Unseal previously sealed Context object.

Methods inherited from class java.lang.Object

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

Field Detail

VERSION_UNKNOWN

public static final int VERSION_UNKNOWN

The unknown version.

VERSION_DEFAULT

public static final int VERSION_DEFAULT

The default version.

VERSION_1_0

public static final int VERSION_1_0

JavaScript 1.0

VERSION_1_1

public static final int VERSION_1_1

JavaScript 1.1

VERSION_1_2

public static final int VERSION_1_2

JavaScript 1.2

VERSION_1_3

public static final int VERSION_1_3

JavaScript 1.3

VERSION_1_4

public static final int VERSION_1_4

JavaScript 1.4

VERSION_1_5

public static final int VERSION_1_5

JavaScript 1.5

languageVersionProperty

public static final java.lang.String languageVersionProperty

errorReporterProperty

public static final java.lang.String errorReporterProperty

emptyArgs

public static final java.lang.Object[] emptyArgs

Convinient value to use as zero-length argument array object.

FEATURE_NON_ECMA_GET_YEAR

public static final int FEATURE_NON_ECMA_GET_YEAR

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

FEATURE_MEMBER_EXPR_AS_FUNCTION_NAME

public static final int FEATURE_MEMBER_EXPR_AS_FUNCTION_NAME

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 simply identifier. See Ecma-262, section 11.2 for definition of memberExpression.

FEATURE_RESERVED_KEYWORD_AS_IDENTIFIER

public static final int FEATURE_RESERVED_KEYWORD_AS_IDENTIFIER

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

FEATURE_TO_STRING_AS_SOURCE

public static final int FEATURE_TO_STRING_AS_SOURCE

If hasFeature(FEATURE_TO_STRING_AS_SOURCE) returns true, calling toString on JS objects gives JS source with code to create an object with all enumeratable fields of the original object instead of printing "[object ]". By default hasFeature(int) returns true only if the current JS version is set to VERSION_1_2.

Constructor Detail

Context

public Context()

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

See Also:

enter()

Method Detail

enter

public static Context enter()

Get a context associated with the current thread, creating one if need be. The Context stores the execution state of the JavaScript engine, so it is required that the context be entered before execution may begin. Once a thread has entered a Context, then getCurrentContext() may be called to find the context that is associated with the current thread.

Calling enter() will return either the Context currently associated with the thread, or will create a new context and associate it with the current thread. Each call to enter() must have a matching call to exit(). For example,

      Context cx = Context.enter();
      try {
          ...
          cx.evaluateString(...);
      } finally {
          Context.exit();
      }
 

Returns:

a Context associated with the current thread

See Also:

getCurrentContext(), exit()

enter

public static Context enter(Context cx)

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

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 enter() 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:

enter()

call

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

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 new Context object will be temporary associated with the thread during call to Callable.

See Also:

enter(), exit()

addContextListener

public static void addContextListener(ContextListener listener)

Add a Context listener.

removeContextListener

public static void removeContextListener(ContextListener listener)

Remove a Context listener.

Parameters:

listener - the listener to remove.

disableStaticContextListening

public static void disableStaticContextListening()

Disable notifications of listeners registered with addContextListener(ContextListener) about Context events. All currently registered listeners will be removed and any subsequent call to addContextListener(ContextListener) will throw an exception.

Embedding may use this method to prevent Context exposure to potentially untrusted code.

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:

enter(), exit()

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.

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

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)
                                      throws JavaScriptException

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

Throws:

JavaScriptException - if an uncaught JavaScript exception occurred while evaluating the source 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,
                                             JavaScriptException

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

JavaScriptException - if an uncaught JavaScript exception occurred while evaluating 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. The method implementation simply calls compileReader(Reader in, String sourceName, int lineno, Object securityDomain) ignoring scope argument.

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,
                                              Scriptable scope,
                                              int indent)

Decompile the script.

The canonical source of the script is returned.

Parameters:

script - the script to decompile

scope - the scope under which 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)
                           throws EvaluatorException,
                                  JavaScriptException

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

Throws:

EvaluatorException - if "Object" cannot be found in the scope or is not a function

JavaScriptException - if an uncaught JavaScript exception occurred while creating the object

newObject

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

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

Throws:

EvaluatorException - if a property with the constructor name cannot be found in the scope or is not a function

JavaScriptException - if an uncaught JavaScript exception occurred while creating the object

newObject

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

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

Throws:

EvaluatorException - if a property with the constructor name cannot be found in the scope or is not a function

JavaScriptException - if an uncaught JavaScript exception occurs while creating the 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. Use toObject(Object, Scriptable) instead.

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.

toType

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

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:

java.lang.IllegalArgumentException - if the conversion cannot be performed

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

setSecurityController

public final void setSecurityController(SecurityController controller)

Set the security controller for this context.

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

Parameters:

controller - a SecurityController object

Throws:

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

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 retreived. 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()

Return whether functions are compiled by this context using dynamic scope.

If functions are compiled with dynamic scope, then they execute in the scope of their caller, rather than in their parent scope. This is useful for sharing functions across multiple scopes.

Since:

1.5 Release 1

setCompileFunctionsWithDynamicScope

public final void setCompileFunctionsWithDynamicScope(boolean flag)

Set whether functions compiled by this context should use dynamic scope.

Parameters:

flag - if true, compile functions with dynamic scope

Since:

1.5 Release 1

setCachingEnabled

public static void setCachingEnabled(boolean cachingEnabled)

Deprecated. To enable/disable caching for a particular top scope, use ClassCache.get(Scriptable) and ClassCache.setCachingEnabled(boolean). The function is kept only for compatibility and does nothing.

setWrapHandler

public final void setWrapHandler(org.mozilla.javascript.WrapHandler wrapHandler)

Deprecated. As of Rhino 1.5 Release 4, use WrapFactory and setWrapFactory(WrapFactory)

getWrapHandler

public final org.mozilla.javascript.WrapHandler getWrapHandler()

Deprecated. As of Rhino 1.5 Release 4, use WrapFactory and getWrapFactory()

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 WrapHandler, or null if none is defined.

Since:

1.5 Release 4

See Also:

WrapHandler

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.

hasFeature

public boolean hasFeature(int featureIndex)

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

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

getInstructionObserverThreshold

public final int getInstructionObserverThreshold()

Get/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.

setInstructionObserverThreshold

public final void setInstructionObserverThreshold(int threshold)

createClassLoader

public org.mozilla.javascript.GeneratedClassLoader createClassLoader(java.lang.ClassLoader parent)

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