Module java.scripting
Package javax.script

Class SimpleScriptContext

  • All Implemented Interfaces:
    ScriptContext

    public class SimpleScriptContext
extends Object
implements ScriptContext
    Simple implementation of ScriptContext.
    Since:
    1.6

    • Field Detail

      • writer

        protected Writer writer
        This is the writer to be used to output from scripts. By default, a PrintWriter based on System.out is used. Accessor methods getWriter, setWriter are used to manage this field.
        See Also:
        System.out, PrintWriter

      • errorWriter

        protected Writer errorWriter
        This is the writer to be used to output errors from scripts. By default, a PrintWriter based on System.err is used. Accessor methods getErrorWriter, setErrorWriter are used to manage this field.
        See Also:
        System.err, PrintWriter

      • reader

        protected Reader reader
        This is the reader to be used for input from scripts. By default, a InputStreamReader based on System.in is used and default charset is used by this reader. Accessor methods getReader, setReader are used to manage this field.
        See Also:
        System.in, InputStreamReader

      • engineScope

        protected Bindings engineScope
        This is the engine scope bindings. By default, a SimpleBindings is used. Accessor methods setBindings, getBindings are used to manage this field.
        See Also:
        SimpleBindings

      • globalScope

        protected Bindings globalScope
        This is the global scope bindings. By default, a null value (which means no global scope) is used. Accessor methods setBindings, getBindings are used to manage this field.

    • Constructor Detail

      • SimpleScriptContext

        public SimpleScriptContext​()
        Create a SimpleScriptContext.

    • Method Detail

      • setBindings

        public void setBindings​(Bindings bindings,
                        int scope)
        Sets a Bindings of attributes for the given scope. If the value of scope is ENGINE_SCOPE the given Bindings replaces the engineScope field. If the value of scope is GLOBAL_SCOPE the given Bindings replaces the globalScope field.
        Specified by:
        setBindings in interface ScriptContext
        Parameters:
        bindings - The Bindings of attributes to set.
        scope - The value of the scope in which the attributes are set.
        Throws:
        IllegalArgumentException - if scope is invalid.
        NullPointerException - if the value of scope is ENGINE_SCOPE and the specified Bindings is null.

      • getAttribute

        public Object getAttribute​(String name)
        Retrieves the value of the attribute with the given name in the scope occurring earliest in the search order. The order is determined by the numeric value of the scope parameter (lowest scope values first.)
        Specified by:
        getAttribute in interface ScriptContext
        Parameters:
        name - The name of the attribute to retrieve.
        Returns:
        The value of the attribute in the lowest scope for which an attribute with the given name is defined. Returns null if no attribute with the name exists in any scope.
        Throws:
        NullPointerException - if the name is null.
        IllegalArgumentException - if the name is empty.

      • getAttribute

        public Object getAttribute​(String name,
                           int scope)
        Gets the value of an attribute in a given scope.
        Specified by:
        getAttribute in interface ScriptContext
        Parameters:
        name - The name of the attribute to retrieve.
        scope - The scope in which to retrieve the attribute.
        Returns:
        The value of the attribute. Returns null is the name does not exist in the given scope.
        Throws:
        IllegalArgumentException - if the name is empty or if the value of scope is invalid.
        NullPointerException - if the name is null.

      • removeAttribute

        public Object removeAttribute​(String name,
                              int scope)
        Remove an attribute in a given scope.
        Specified by:
        removeAttribute in interface ScriptContext
        Parameters:
        name - The name of the attribute to remove
        scope - The scope in which to remove the attribute
        Returns:
        The removed value.
        Throws:
        IllegalArgumentException - if the name is empty or if the scope is invalid.
        NullPointerException - if the name is null.

      • setAttribute

        public void setAttribute​(String name,
                         Object value,
                         int scope)
        Sets the value of an attribute in a given scope. If the scope is GLOBAL_SCOPE and no Bindings is set for GLOBAL_SCOPE, then setAttribute call is a no-op.
        Specified by:
        setAttribute in interface ScriptContext
        Parameters:
        name - The name of the attribute to set
        value - The value of the attribute
        scope - The scope in which to set the attribute
        Throws:
        IllegalArgumentException - if the name is empty or if the scope is invalid.
        NullPointerException - if the name is null.

      • getWriter

        public Writer getWriter​()
        Returns the Writer for scripts to use when displaying output.
        Specified by:
        getWriter in interface ScriptContext
        Returns:
        The Writer.

      • getReader

        public Reader getReader​()
        Returns a Reader to be used by the script to read input.
        Specified by:
        getReader in interface ScriptContext
        Returns:
        The Reader.

      • setReader

        public void setReader​(Reader reader)
        Sets the Reader for scripts to read input .
        Specified by:
        setReader in interface ScriptContext
        Parameters:
        reader - The new Reader.

      • setWriter

        public void setWriter​(Writer writer)
        Sets the Writer for scripts to use when displaying output.
        Specified by:
        setWriter in interface ScriptContext
        Parameters:
        writer - The new Writer.

      • getErrorWriter

        public Writer getErrorWriter​()
        Returns the Writer used to display error output.
        Specified by:
        getErrorWriter in interface ScriptContext
        Returns:
        The Writer

      • setErrorWriter

        public void setErrorWriter​(Writer writer)
        Sets the Writer used to display error output.
        Specified by:
        setErrorWriter in interface ScriptContext
        Parameters:
        writer - The Writer.

      • getAttributesScope

        public int getAttributesScope​(String name)
        Get the lowest scope in which an attribute is defined.
        Specified by:
        getAttributesScope in interface ScriptContext
        Parameters:
        name - Name of the attribute .
        Returns:
        The lowest scope. Returns -1 if no attribute with the given name is defined in any scope.
        Throws:
        NullPointerException - if name is null.
        IllegalArgumentException - if name is empty.

      • getBindings

        public Bindings getBindings​(int scope)
        Returns the value of the engineScope field if specified scope is ENGINE_SCOPE. Returns the value of the globalScope field if the specified scope is GLOBAL_SCOPE.
        Specified by:
        getBindings in interface ScriptContext
        Parameters:
        scope - The specified scope
        Returns:
        The value of either the engineScope or globalScope field.
        Throws:
        IllegalArgumentException - if the value of scope is invalid.

      • getScopes

        public List<Integer> getScopes​()
        Returns immutable List of all the valid values for scope in the ScriptContext.
        Specified by:
        getScopes in interface ScriptContext
        Returns:
        list of scope values