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

All Implemented Interfaces:

HierarchicalAware, Interpreter, SerializableAware
```
public class BSHInterpreter
extends GenericInterpreter
implements SerializableAware, HierarchicalAware
```
The interpreter that uses BeanShell to interpret zscript codes.
Unlike many other implementations, it supports the hierarchical scopes (HierarchicalAware). That is, it uses an independent BeanShell NameSpace (a.k.a. interpreter's scope) to store the variables/classes/methods defined in BeanShell script for each ZK scope (Scope). Since one-to-one relationship between BeanShell's scope and ZK scope, the invocation of BeanShell methods can execute correctly without knowing what scope it is. However, if you want your codes portable across different interpreters, you had better to call Scopes.beforeInterpret(org.zkoss.zk.ui.ext.Scope) to prepare the proper scope, before calling any method defined in zscript.
How serialization work?

First, all NameSpace objects have to serialize. Second, the top-level namespace (GlobalNS) is wrapped with NSWrap, which is not serializable. It is serialized when SerializableAware.write(java.io.ObjectOutputStream, org.zkoss.zk.scripting.SerializableAware.Filter) is called (triggered by PageImpl's write).
On the other hand, all non-top-level namespaces (NS) are wrapped with NSWrapSR which is serializable, so they are serialized with the attributes of a ID space owner being serialized.

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

Constructors
Constructor Description

BSHInterpreter()

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`protected boolean`	`contains(java.lang.String name)`	Tests whether a variable is defined in this interpreter.
`protected boolean`	`contains(Scope scope, java.lang.String name)`	Tests whether a variable is defined in the interpreter's scope associated with the specified scope.
`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(java.lang.String name)`	Gets the variable from the interpreter.
`protected java.lang.Object`	`get(Scope scope, java.lang.String name)`	Gets the variable from the interpreter's scope associated with the giving scope.
`java.lang.Class<?>`	`getClass(java.lang.String clsnm)`	Returns null since retrieving class is not supported.
`Function`	`getFunction(java.lang.String name, java.lang.Class[] argTypes)`	Returns null since retrieving methods is not supported.
`Function`	`getFunction(Scope scope, java.lang.String name, java.lang.Class[] argTypes)`	Returns null since retrieving methods is not supported.
`java.lang.Object`	`getNativeInterpreter()`	Returns the native interpreter, or null if it is not initialized or destroyed.
`void`	`init(Page owner, java.lang.String zslang)`	Initializes the interpreter.
`protected void`	`loadDefaultImports(bsh.NameSpace bshns)`	Called when the top-level BeanShell scope is created.
`void`	`read(java.io.ObjectInputStream s)`	Reads the name and value of the variable from the specified input stream.
`protected void`	`set(java.lang.String name, java.lang.Object val)`	Sets the variable to the interpreter.
`protected void`	`set(Scope scope, java.lang.String name, java.lang.Object val)`	Sets the variable to the interpreter's scope associated with the giving scope.
`protected void`	`unset(java.lang.String name)`	Removes the variable from the interpreter.
`protected void`	`unset(Scope scope, 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, getImplicit, 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.HierarchicalAware
containsVariable, getVariable, setVariable, unsetVariable

- Constructor Detail
  - BSHInterpreter
```
public BSHInterpreter()
```
- Method Detail
  - loadDefaultImports
```
protected void loadDefaultImports(bsh.NameSpace bshns)
```
    Called when the top-level BeanShell scope is created. By default, it does nothing.
    Note: to speed up the performance, this implementation disabled NameSpace.loadDefaultImports(). It only imports the java.lang and java.util packages. If you want the built command and import packages, you can override this method. For example,
    protected void loadDefaultImports(NameSpace bshns) { bshns.importCommands("/bsh/commands"); }
    Since:
    
    3.0.2
  - 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.ui.ext.Scope).
    
    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
  - contains
```
protected boolean contains(Scope scope,
                           java.lang.String name)
```
    Description copied from class: GenericInterpreter
    
    Tests whether a variable is defined in the interpreter's scope associated with the specified scope. Optional. Implement it if the interpreter can tell the difference between null and undefined.
    By default, it tests whether GenericInterpreter.get(Scope, 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) scope is pushed so GenericInterpreter.getFromNamespace(java.lang.String) always returns null.
    
    Overrides:
    
    get in class GenericInterpreter
  - get
```
protected java.lang.Object get(Scope scope,
                               java.lang.String name)
```
    Description copied from class: GenericInterpreter
    
    Gets the variable from the interpreter's scope associated with the giving scope. 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 hierarchical scopes (HierarchicalAware).
    Default: the same as GenericInterpreter.get(String).
    GenericInterpreter.beforeExec() is called first, before this method is invoked.
    An empty (and fake) scope 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
  - set
```
protected void set(Scope scope,
                   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 scope. 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 hierarchical scopes (HierarchicalAware).
    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(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
  - unset
```
protected void unset(Scope scope,
                     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 hierarchical scopes (HierarchicalAware).
    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
  - getNativeInterpreter
```
public java.lang.Object getNativeInterpreter()
```
    Returns the native interpreter, or null if it is not initialized or destroyed. From application's standpoint, it never returns null, and the returned object must be an instance of Interpreter
    
    Specified by:
    
    getNativeInterpreter in interface Interpreter
    
    Since:
    
    3.0.2
  - 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
  - getFunction
```
public Function getFunction(java.lang.String name,
                            java.lang.Class[] argTypes)
```
    Description copied from class: GenericInterpreter
    
    Returns null since retrieving methods is not supported.
    
    Specified by:
    
    getFunction in interface Interpreter
    
    Overrides:
    
    getFunction in class GenericInterpreter
    
    argTypes - the list of argument (a.k.a., parameter) types. If null, Class[0] is assumed.
  - getFunction
```
public Function getFunction(Scope scope,
                            java.lang.String name,
                            java.lang.Class[] argTypes)
```
    Description copied from class: GenericInterpreter
    
    Returns null since retrieving methods is not supported.
    
    Specified by:
    
    getFunction in interface HierarchicalAware
    
    Overrides:
    
    getFunction in class GenericInterpreter
    
    Parameters:
    
    scope - the scope used as a reference to identify the correct scope for searching the method. Note: this method doesn't look for any variable stored in scope.
    
    argTypes - the list of argument (a.k.a., 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)

Class BSHInterpreter

Nested Class Summary

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

Field Summary

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

Constructor Summary

Method Summary

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

Methods inherited from class java.lang.Object

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

Constructor Detail

BSHInterpreter

Method Detail

loadDefaultImports

exec

contains

contains

get

get

set

set

unset

unset

init

destroy

getNativeInterpreter

getClass

getFunction

getFunction

write

read