org.apache.cocoon.components.xscript
Interface XScriptManager

All Known Implementing Classes:

XScriptManagerImpl

public interface XScriptManager

XScriptManager is the public interface used to interact with the XScript component, which implements the supporting code for the XScript language.

Since:

August 4, 2001

Author:

Ovidiu Predescu

Field Summary

static int	ALL_SCOPES Search for a variable in all the accessible scopes.
static int	GLOBAL_SCOPE The variable's global scope.
static int	PAGE_SCOPE The page scope.
static java.lang.String	ROLE
static int	SESSION_SCOPE The session scope.
static java.lang.String	XSCRIPT_NS

Method Summary

XScriptObject	get(java.lang.String name, int scope, java.lang.String context) Obtains the object value of the name variable in scope.
XScriptObject	getFirst(java.lang.String name, java.lang.String sessionContext, java.lang.String pageContext) Search for the first occurence of the variable name.
void	put(java.lang.String name, XScriptObject value, int scope, java.lang.String context) Defines or overwrites the value of variable name in scope.
void	remove(java.lang.String name, int scope, java.lang.String context) Removes a variable previously declared in scope within context.
void	removeFirst(java.lang.String name, java.lang.String sessionContext, java.lang.String pageContext) Remove the first appearance of name in the all the currently accessible scopes.

Field Detail

ROLE

public static final java.lang.String ROLE

XSCRIPT_NS

public static final java.lang.String XSCRIPT_NS

GLOBAL_SCOPE

public static final int GLOBAL_SCOPE

The variable's global scope. Each Cocoon instance has exactly one global scope for variables.

SESSION_SCOPE

public static final int SESSION_SCOPE

The session scope. This scope is specific to a particular activation of an XSP page, which is usually identified by the session id of the user that sent the HTTP request. From XScript's point of view however, the session identifier is not interpreted in any way, so a client can define its own notion of "session".

PAGE_SCOPE

public static final int PAGE_SCOPE

The page scope. This is scope very specific to an XSP page, and defines variables visible only within the context of that page. No other XSP page can access these variables, unless it knows the identifier used by that page to store its variables. This identifier is not necessarily the URL or full path of that page; it is up to the page to define it.

ALL_SCOPES

public static final int ALL_SCOPES

Search for a variable in all the accessible scopes. The variable is first searched in the current session scope. If no variable is found here, the current page scope is searched next. If nothing is found either, the global scope is searched.

Method Detail

get

public XScriptObject get(java.lang.String name,
                         int scope,
                         java.lang.String context)
                  throws java.lang.IllegalArgumentException

Obtains the object value of the name variable in scope. The context parameter is interpreted differently depending on the value of scope, as follows:

• if scope is GLOBAL_SCOPE, the value of context is ignored.
• if scope is SESSION_SCOPE, the value of context is interpreted as the session identifier.
• if scope is PAGE_SCOPE, the value of context is interpreted as an identifier of the page. This could be the URL of the page or the path of the file name in the file system.

Parameters:

name - a String value

scope - an int value

context - a String value whose interpretation depends on scope

Returns:

a XScriptObject value

getFirst

public XScriptObject getFirst(java.lang.String name,
                              java.lang.String sessionContext,
                              java.lang.String pageContext)
                       throws java.lang.IllegalArgumentException

Search for the first occurence of the variable name.

The search happens first in the session scope identified by sessionContext. If no variable is found here, the search continues in the page scope identified by pageContext. If no variable is found here, it's finally searched in the global scope.

The XScriptObject value of the variable is returned if a variable is found in one of the scopes, otherwise an exception is thrown.

Parameters:

name - a String value

sessionContext - a String value

pageContext - a String value

Returns:

a XScriptObject value

Throws:

java.lang.IllegalArgumentException - if an error occurs

put

public void put(java.lang.String name,
                XScriptObject value,
                int scope,
                java.lang.String context)
         throws java.lang.IllegalArgumentException

Defines or overwrites the value of variable name in scope. The context argument is interpreted as described in get(String, int, String).

Parameters:

name - a String value

value - a XScriptObject value

scope - an int value

context - a String value whose interpretation depends on scope

remove

public void remove(java.lang.String name,
                   int scope,
                   java.lang.String context)

Removes a variable previously declared in scope within context. Such a variable could be declared using the put(String, XScriptObject, int, String) method.

Parameters:

name - a String value

scope - an int value

context - a String value

removeFirst

public void removeFirst(java.lang.String name,
                        java.lang.String sessionContext,
                        java.lang.String pageContext)
                 throws java.lang.IllegalArgumentException

Remove the first appearance of name in the all the currently accessible scopes. The search happens as described in getFirst(String,String,String).

Parameters:

name - a String value

sessionContext - a String value

pageContext - a String value

Throws:

java.lang.IllegalArgumentException - if an error occurs