LocalGlobalVariable.java
/**
* **** BEGIN LICENSE BLOCK *****
* Version: EPL 1.0/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Eclipse Public
* License Version 1.0 (the "License"); you may not use this file
* except in compliance with the License. You may obtain a copy of
* the License at http://www.eclipse.org/legal/epl-v10.html
*
* Software distributed under the License is distributed on an "AS
* IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
* implied. See the License for the specific language governing
* rights and limitations under the License.
*
* Copyright (C) 2009-2012 Yoko Harada <yokolet@gmail.com>
*
* Alternatively, the contents of this file may be used under the terms of
* either of the GNU General Public License Version 2 or later (the "GPL"),
* or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the EPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the EPL, the GPL or the LGPL.
* **** END LICENSE BLOCK *****
*/
package org.jruby.embed.variable;
import java.util.Set;
import org.jruby.Ruby;
import org.jruby.RubyObject;
import org.jruby.embed.internal.BiVariableMap;
import org.jruby.internal.runtime.GlobalVariables;
import org.jruby.runtime.builtin.IRubyObject;
/**
* An implementation of BiVariable for JSR223 style global variable. The assigned
* name is like a local variables in Java, but a global in Ruby.
*
* @author Yoko Harada <yokolet@gmail.com>
*/
public class LocalGlobalVariable extends GlobalVariable {
private static String pattern = "([a-zA-Z]|(_([a-zA-Z]|_|\\d)))([a-zA-Z]|_|\\d)*";
/**
* Returns an instance of this class. This factory method is used when a local
* global type variable is put into {@link BiVariableMap}.
*
* @param runtime Ruby runtime
* @param name a variable name
* @param javaObject Java object that should be assigned to.
* @return the instance of LocalGlobalVariable
*/
public static BiVariable getInstance(RubyObject receiver, String name, Object... javaObject) {
if (name.matches(pattern)) {
return new LocalGlobalVariable(receiver, name, javaObject);
}
return null;
}
private LocalGlobalVariable(RubyObject receiver, String name, Object... javaObject) {
super(receiver, name, javaObject);
}
/**
* A constructor used when local global type variables are retrieved from Ruby.
*
* @param name the local global type variable name
* @param irubyObject Ruby global object
*/
LocalGlobalVariable(IRubyObject receiver, String name, IRubyObject irubyObject) {
super(receiver, name, irubyObject);
}
/**
* Retrieves global variables eagerly from Ruby right after the evaluation. The
* variable names to be retrieved must be in a variable map.
*
* @param receiver receiver object returned when a script is evaluated.
* @param vars map to save retrieved global variables.
*/
public static void retrieve(RubyObject receiver, BiVariableMap vars) {
if (vars.isLazy()) return;
GlobalVariables gvars = receiver.getRuntime().getGlobalVariables();
Set<String> names = gvars.getNames();
for (String name : names) {
if (isPredefined(name)) {
continue;
}
IRubyObject value = gvars.get(name);
String javaName = name.substring(1); // eliminates a preceding character, "$"
updateLocalGlobal((RubyObject)receiver.getRuntime().getTopSelf(), vars, javaName, value);
}
}
private static void updateLocalGlobal(RubyObject receiver, BiVariableMap vars, String name, IRubyObject value) {
BiVariable var;
if (vars.containsKey((Object) name)) {
var = vars.getVariable(receiver, name);
var.setRubyObject(value);
} else {
var = new LocalGlobalVariable(receiver, name, value);
vars.update(name, var);
}
}
/**
* Retrieves a global variable by key from Ruby runtime after the evaluation.
* This method is used when eager retrieval is off.
*
* @param runtime Ruby runtime
* @param vars map to save a retrieved global variable.
* @param key name of the global variable
*/
public static void retrieveByKey(Ruby runtime, BiVariableMap vars, String key) {
GlobalVariables gvars = runtime.getGlobalVariables();
// if the specified key doesn't exist, this method is called before the
// evaluation. Don't update value in this case.
String rubyKey = ("$" + key).intern();
if (!gvars.getNames().contains(rubyKey)) return;
// the specified key is found, so let's update
IRubyObject value = gvars.get(rubyKey);
updateLocalGlobal((RubyObject)runtime.getTopSelf(), vars, key, value);
}
/**
* Returns enum type of this variable defined in {@link BiVariable}.
*
* @return this enum type, BiVariable.Type.GlobalVariable.
*/
@Override
public Type getType() {
return Type.LocalGlobalVariable;
}
/**
* Returns true if the given name is a local global type variable. Unless
* returns false.
*
* @param name is a name to be checked.
* @return true if the given name is of a local global type variable.
*/
public static boolean isValidName(Object name) {
return isValidName(pattern, name);
}
/**
* Injects a global value to a parsed Ruby script. This method is
* invoked during EvalUnit#run() is executed.
*/
@Override
public void inject() {
synchronized (receiver.getRuntime()) {
String varname = (name.startsWith("$") ? name : "$" + name);
receiver.getRuntime().getGlobalVariables().set(varname.intern(), irubyObject);
}
}
/**
* Removes this object from {@link BiVariableMap}.
*
* @param runtime environment where a variable is removed.
*/
@Override
public void remove() {
synchronized (receiver.getRuntime()) {
String varname = (name.startsWith("$") ? name : "$" + name);
receiver.getRuntime().getGlobalVariables().clear(varname.intern());
}
}
}