Package org.mozilla.javascript

Class 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.

    See Also:
    Scriptable

    • 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

      • 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

        @Deprecated
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 create a 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 behavior 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

      • FEATURE_V8_EXTENSIONS

        public static final int FEATURE_V8_EXTENSIONS
        Enables access to JavaScript features from ECMAscript 6 that are present in JavaScript engines that do not yet support version 6, such as V8. This includes support for typed arrays. Default is true.
        Since:
        1.7 Release 3
        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

        @Deprecated
public Context()
        Deprecated.
        this constructor is deprecated because it creates a dependency on a static singleton context factory. Use ContextFactory.enter() or ContextFactory.call(ContextAction) instead. If you subclass this class, consider using Context(ContextFactory) constructor instead in the subclasses' constructors.
        Creates a new Context. The context will be associated with the global context factory. 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

        @Deprecated
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()

      • 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.

      • 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

      • initSafeStandardObjects

        public final ScriptableObject initSafeStandardObjects()
        Initialize the standard objects, leaving out those that offer access directly to Java classes. This sets up "scope" to have access to all the standard JavaScript classes, but does not create global objects for any top-level Java packages. In addition, the "Packages," "JavaAdapter," and "JavaImporter" classes, and the "getClass" function, are not initialized. The result of this function is a scope that may be safely used in a "sandbox" environment where it is not desirable to give access to Java code from JavaScript. 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.

      • initSafeStandardObjects

        public final Scriptable initSafeStandardObjects​(ScriptableObject scope)
        Initialize the standard objects, leaving out those that offer access directly to Java classes. This sets up "scope" to have access to all the standard JavaScript classes, but does not create global objects for any top-level Java packages. In addition, the "Packages," "JavaAdapter," and "JavaImporter" classes, and the "getClass" function, are not initialized. The result of this function is a scope that may be safely used in a "sandbox" environment where it is not desirable to give access to Java code from JavaScript. 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

      • initSafeStandardObjects

        public ScriptableObject initSafeStandardObjects​(ScriptableObject scope,
                                                boolean sealed)
        Initialize the standard objects, leaving out those that offer access directly to Java classes. This sets up "scope" to have access to all the standard JavaScript classes, but does not create global objects for any top-level Java packages. In addition, the "Packages," "JavaAdapter," and "JavaImporter" classes, and the "getClass" function, are not initialized. The result of this function is a scope that may be safely used in a "sandbox" environment where it is not desirable to give access to Java code from JavaScript. 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:
        1.7.6

      • 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

      • executeScriptWithContinuations

        public java.lang.Object executeScriptWithContinuations​(Script script,
                                                       Scriptable scope)
                                                throws ContinuationPending
        Execute script that may pause execution by capturing a continuation. Caller must be prepared to catch a ContinuationPending exception and resume execution by calling resumeContinuation(Object, Scriptable, Object).
        Parameters:
        script - The script to execute. Script must have been compiled with interpreted mode (optimization level -1)
        scope - The scope to execute the script against
        Throws:
        ContinuationPending - if the script calls a function that results in a call to captureContinuation()
        Since:
        1.7 Release 2

      • callFunctionWithContinuations

        public java.lang.Object callFunctionWithContinuations​(Callable function,
                                                      Scriptable scope,
                                                      java.lang.Object[] args)
                                               throws ContinuationPending
        Call function that may pause execution by capturing a continuation. Caller must be prepared to catch a ContinuationPending exception and resume execution by calling resumeContinuation(Object, Scriptable, Object).
        Parameters:
        function - The function to call. The function must have been compiled with interpreted mode (optimization level -1)
        scope - The scope to execute the script against
        args - The arguments for the function
        Throws:
        ContinuationPending - if the script calls a function that results in a call to captureContinuation()
        Since:
        1.7 Release 2

      • resumeContinuation

        public java.lang.Object resumeContinuation​(java.lang.Object continuation,
                                           Scriptable scope,
                                           java.lang.Object functionResult)
                                    throws ContinuationPending
        Restarts execution of the JavaScript suspended at the call to captureContinuation(). Execution of the code will resume with the functionResult as the result of the call that captured the continuation. Execution of the script will either conclude normally and the result returned, another continuation will be captured and thrown, or the script will terminate abnormally and throw an exception.
        Parameters:
        continuation - The value returned by ContinuationPending.getContinuation()
        functionResult - This value will appear to the code being resumed as the result of the function that captured the continuation
        Throws:
        ContinuationPending - if another continuation is captured before the code terminates
        Since:
        1.7 Release 2

      • 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​(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. Use 0 if the line number is unknown.
        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 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 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 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 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 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

      • 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

        @Deprecated
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

      • 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

      • 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 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​(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.

      • getE4xImplementationFactory

        public 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.

      • 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