org.zkoss.zk.scripting.bsh
Class BSHInterpreter

java.lang.Object
  org.zkoss.zk.scripting.util.GenericInterpreter
      org.zkoss.zk.scripting.bsh.BSHInterpreter

All Implemented Interfaces:

HierachicalAware, Interpreter, SerializableAware

public class BSHInterpreter
extends GenericInterpreter
implements SerializableAware, HierachicalAware

The interpreter that uses BeanShell to interpret zscript codes.

Unlike many other implementations, it supports the hierachical scopes (HierachicalAware). That is, it uses an independent BeanShell NameSpace (aka. interpreter's scope) to store the variables/classes/methods defined in BeanShell script for each ZK namespace (Namespace). Since one-to-one relationship between BeanShell's scope and ZK namespace, the invocation of BeanShell methods can execute correctly without knowing what namespace it is. However, if you want your codes portable across different interpreters, you had better to call Namespaces.beforeInterpret(java.util.Map, org.zkoss.zk.ui.Component, boolean) to prepare the proper namespace, before calling any method defined in zscript.

Author:

tomyeh

Nested Class Summary

Nested classes/interfaces inherited from interface org.zkoss.zk.scripting.SerializableAware

SerializableAware.Filter

Field Summary

Fields inherited from class org.zkoss.zk.scripting.util.GenericInterpreter

UNDEFINED

Constructor Summary

BSHInterpreter()

Method Summary

protected boolean	contains(Namespace ns, java.lang.String name) Tests whether a variable is defined in the interpreter's scope associated with the specified namespace.
protected boolean	contains(java.lang.String name) Tests whether a variable is defined in this interpreter.
void	destroy() Reset the owner (GenericInterpreter.getOwner()) to null.
protected void	exec(java.lang.String script) Executes the specified script.
protected java.lang.Object	get(Namespace ns, java.lang.String name) Gets the variable from the interpreter's scope associated with the giving namespace.
protected java.lang.Object	get(java.lang.String name) Gets the variable from the interpreter.
java.lang.Class	getClass(java.lang.String clsnm) Returns null since retrieving class is not supported.
Method	getMethod(Namespace ns, java.lang.String name, java.lang.Class[] argTypes) Returns null since retrieving methods is not supported.
Method	getMethod(java.lang.String name, java.lang.Class[] argTypes) Returns null since retrieving methods is not supported.
void	init(Page owner, java.lang.String zslang) Initializes the interpreter.
void	read(java.io.ObjectInputStream s) Reads the name and value of the variable from the specified input stream.
protected void	set(Namespace ns, java.lang.String name, java.lang.Object val) Sets the variable to the interpreter's scope associated with the giving namespace.
protected void	set(java.lang.String name, java.lang.Object val) Sets the variable to the interpreter.
protected void	unset(Namespace ns, java.lang.String name) Removes the variable from the interpreter.
protected void	unset(java.lang.String name) Removes the variable from the interpreter.
void	write(java.io.ObjectOutputStream s, SerializableAware.Filter filter) Writes the name and value of the variables of this namespace to the specified stream.

Methods inherited from class org.zkoss.zk.scripting.util.GenericInterpreter

afterExec, afterInterpret, beforeExec, beforeInterpret, containsVariable, containsVariable, getCurrent, getFromNamespace, getFromNamespace, getLanguage, getOwner, getVariable, getVariable, interpret, setVariable, setVariable, unsetVariable, unsetVariable

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.zkoss.zk.scripting.HierachicalAware

containsVariable, getVariable, setVariable, unsetVariable

Constructor Detail

BSHInterpreter

public BSHInterpreter()

Method Detail

exec

protected void exec(java.lang.String script)

Description copied from class: GenericInterpreter

Executes the specified script. Deriving class shall provide an implementation of this method, rather than overriding GenericInterpreter.interpret(java.lang.String, org.zkoss.zk.scripting.Namespace).

Specified by:

exec in class GenericInterpreter

contains

protected boolean contains(java.lang.String name)

Description copied from class: GenericInterpreter

Tests whether a variable is defined in this interpreter. Optional. Implement it if the interpreter can tell the difference between null and undefined.

By default, it tests whether GenericInterpreter.get(String) returns non-null.

Overrides:

contains in class GenericInterpreter

get

protected java.lang.Object get(java.lang.String name)

Description copied from class: GenericInterpreter

Gets the variable from the interpreter. Optional. Implement it if you want to expose variables defined in the interpreter to Java codes.

GenericInterpreter.beforeExec() is called first, before this method is invoked.

An empty (and fake) namespace is pushed so GenericInterpreter.getFromNamespace(java.lang.String) always returns null.

Overrides:

get in class GenericInterpreter

set

protected void set(java.lang.String name,
                   java.lang.Object val)

Description copied from class: GenericInterpreter

Sets the variable to the interpreter. Optional. Implement it if you want to allow Java codes to define a variable in the interpreter.

GenericInterpreter.beforeExec() is called first, before this method is invoked.

Overrides:

set in class GenericInterpreter

unset

protected void unset(java.lang.String name)

Description copied from class: GenericInterpreter

Removes the variable from the interpreter. Optional. Implement it if you want to allow Java codes to undefine a variable from the interpreter.

GenericInterpreter.beforeExec() is called first, before this method is invoked.

Overrides:

unset in class GenericInterpreter

contains

protected boolean contains(Namespace ns,
                           java.lang.String name)

Description copied from class: GenericInterpreter

Tests whether a variable is defined in the interpreter's scope associated with the specified namespace. Optional. Implement it if the interpreter can tell the difference between null and undefined.

By default, it tests whether GenericInterpreter.get(Namespace, String) returns non-null.

Overrides:

contains in class GenericInterpreter

get

protected java.lang.Object get(Namespace ns,
                               java.lang.String name)

Description copied from class: GenericInterpreter

Gets the variable from the interpreter's scope associated with the giving namespace. Optional. Implement it if you want to expose variables defined in the interpreter to Java codes.

This method is implemented only if the interpreter that supports hierachical scopes (HierachicalAware).

Default: the same as GenericInterpreter.get(String).

GenericInterpreter.beforeExec() is called first, before this method is invoked.

An empty (and fake) namespace is pushed so GenericInterpreter.getFromNamespace(java.lang.String) always returns null.

Overrides:

get in class GenericInterpreter

set

protected void set(Namespace ns,
                   java.lang.String name,
                   java.lang.Object val)

Description copied from class: GenericInterpreter

Sets the variable to the interpreter's scope associated with the giving namespace. Optional. Implement it if you want to allow Java codes to define a variable in the interpreter.

This method is implemented only if the interpreter that supports hierachical scopes (HierachicalAware).

Default: the same as GenericInterpreter.set(String, Object).

GenericInterpreter.beforeExec() is called first, before this method is invoked.

Overrides:

set in class GenericInterpreter

unset

protected void unset(Namespace ns,
                     java.lang.String name)

Description copied from class: GenericInterpreter

Removes the variable from the interpreter. Optional. Implement it if you want to allow Java codes to undefine a variable from the interpreter.

This method is implemented only if the interpreter that supports hierachical scopes (HierachicalAware).

Default: the same as GenericInterpreter.unset(String).

GenericInterpreter.beforeExec() is called first, before this method is invoked.

Overrides:

unset in class GenericInterpreter

init

public void init(Page owner,
                 java.lang.String zslang)

Description copied from interface: Interpreter

Initializes the interpreter. It is called once when the new instance of interpreter is constructed.

Specified by:

init in interface Interpreter

Overrides:

init in class GenericInterpreter

zslang - the language this interpreter is associated with

destroy

public void destroy()

Description copied from class: GenericInterpreter

Reset the owner (GenericInterpreter.getOwner()) to null.

Specified by:

destroy in interface Interpreter

Overrides:

destroy in class GenericInterpreter

getClass

public java.lang.Class getClass(java.lang.String clsnm)

Description copied from class: GenericInterpreter

Returns null since retrieving class is not supported.

Specified by:

getClass in interface Interpreter

Overrides:

getClass in class GenericInterpreter

getMethod

public Method getMethod(java.lang.String name,
                        java.lang.Class[] argTypes)

Description copied from class: GenericInterpreter

Returns null since retrieving methods is not supported.

Specified by:

getMethod in interface Interpreter

Overrides:

getMethod in class GenericInterpreter

argTypes - the list of argument (aka., parameter) types. If null, Class[0] is assumed.

getMethod

public Method getMethod(Namespace ns,
                        java.lang.String name,
                        java.lang.Class[] argTypes)

Description copied from class: GenericInterpreter

Returns null since retrieving methods is not supported.

Specified by:

getMethod in interface HierachicalAware

Overrides:

getMethod in class GenericInterpreter

Parameters:

ns - the namespace used as a reference to identify the correct scope for searching the method. Note: this method doesn't look for any variable stored in ns.

argTypes - the list of argument (aka., parameter) types. If null, Class[0] is assumed.

write

public void write(java.io.ObjectOutputStream s,
                  SerializableAware.Filter filter)
           throws java.io.IOException

Description copied from interface: SerializableAware

Writes the name and value of the variables of this namespace to the specified stream.

If the variable's value is not serializable, it won't be written.

To read back, use SerializableAware.read(java.io.ObjectInputStream).

Specified by:

write in interface SerializableAware

Throws:

java.io.IOException

read

public void read(java.io.ObjectInputStream s)
          throws java.io.IOException,
                 java.lang.ClassNotFoundException

Description copied from interface: SerializableAware

Reads the name and value of the variable from the specified input stream.

Specified by:

read in interface SerializableAware

Throws:

java.io.IOException

java.lang.ClassNotFoundException

See Also:

SerializableAware.write(java.io.ObjectOutputStream, org.zkoss.zk.scripting.SerializableAware.Filter)