/**
* **** BEGIN LICENSE BLOCK *****
* Version: CPL 1.0/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Common 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/cpl-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) 2009-2011 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 CPL, 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 CPL, the GPL or the LGPL.
* **** END LICENSE BLOCK *****
*/
package org.jruby.embed.variable;
import org.jruby.RubyObject;
import org.jruby.parser.EvalStaticScope;
import org.jruby.embed.internal.BiVariableMap;
import org.jruby.runtime.DynamicScope;
import org.jruby.runtime.ThreadContext;
import org.jruby.runtime.builtin.IRubyObject;
import org.jruby.runtime.scope.ManyVarsDynamicScope;
/**
* An implementation of BiVariable for a persistent local variable. This type of
* a local variable survives over multiple evaluation.
*
* @author Yoko Harada <yokolet@gmail.com>
*/
public class PersistentLocalVariable extends AbstractVariable {
private static String pattern = "([a-z]|_)([a-zA-Z]|_|\\d)*";
/**
* Returns an instance of this class. This factory method is used when a
* persistent local variable is put in {@link BiVariableMap}.
*
* @param runtime Ruby runtime
* @param name a variable name
* @param javaObject Java object that should be assigned to.
* @return the instance of PersistentLocalVariable
*/
public static BiVariable getInstance(RubyObject receiver, String name, Object... javaObject) {
if (name.matches(pattern)) {
return new PersistentLocalVariable(receiver, name, javaObject);
}
return null;
}
private PersistentLocalVariable(RubyObject receiver, String name, Object... javaObjects) {
super(receiver, name, false);
updateByJavaObject(receiver.getRuntime(), javaObjects);
}
/**
* A constructor used when persistent local variables are retrieved from Ruby.
*
* @param name the persistent local variable name
* @param irubyObject Ruby local object
*/
PersistentLocalVariable(IRubyObject origin, String name, IRubyObject irubyObject) {
super(origin, name, true, irubyObject);
}
/**
* Returns enum type of this variable defined in {@link BiVariable}.
*
* @return this enum type, BiVariable.Type.LocalVariable.
*/
public Type getType() {
return Type.LocalVariable;
}
/**
* Returns true if the given name is a decent Ruby local variable. Unless
* returns false.
*
* @param name is a name to be checked.
* @return true if the given name is of a Ruby local variable.
*/
public static boolean isValidName(Object name) {
return isValidName(pattern, name);
}
/**
* Retrieves local variables from Ruby after the evaluation. This retrieval doesn't
* depend on eager option. Local variables are always retrieved eagerly.
*
* @param runtime Ruby runtime
* @param receiver receiver object returned when a script is evaluated.
* @param vars map to save retrieved local variables.
*/
public static void retrieve(RubyObject receiver, BiVariableMap vars) {
ManyVarsDynamicScope scope =
(ManyVarsDynamicScope) receiver.getRuntime().getCurrentContext().getCurrentScope();
if (scope == null) {
return;
}
String[] names = scope.getAllNamesInScope();
IRubyObject[] values = scope.getValues();
if (names == null || values == null || names.length == 0 || values.length == 0) {
return;
}
// Local variable is always saved as a top level variable.
for (int i=0; i<names.length; i++) {
BiVariable var;
if ((var = vars.getVariable((RubyObject)receiver.getRuntime().getTopSelf(), names[i])) != null
&& receiver.getRuntime().getTopSelf() == var.getReceiver()) {
var.setRubyObject(values[i]);
} else {
var = new PersistentLocalVariable(receiver.getRuntime().getTopSelf(), names[i], values[i]);
vars.update(names[i], var);
}
}
}
/**
* Injects a local variable value to a parsed Ruby script. This method is
* invoked during EvalUnit#run() is executed.
*/
public void inject() {
//done in JRubyVariableMap.inject()
}
/**
* Attempts to remove this variable from top self or receiver.
*
*/
public void remove() {
ThreadContext context = receiver.getRuntime().getCurrentContext();
try {
DynamicScope currentScope = context.getCurrentScope();
ManyVarsDynamicScope scope = (ManyVarsDynamicScope) context.getCurrentScope();
scope = new ManyVarsDynamicScope(new EvalStaticScope(currentScope.getStaticScope()), currentScope);
} catch (ArrayIndexOutOfBoundsException e) {
//no context is left.
//no operation is needed.
}
}
}