/**
* **** 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.embed.internal.BiVariableMap;
import java.util.Collection;
import java.util.List;
import java.util.Map;
import org.jruby.RubyModule;
import org.jruby.RubyObject;
import org.jruby.javasupport.JavaUtil;
import org.jruby.runtime.builtin.IRubyObject;
/**
* An implementation of BiVariable for a Ruby constant.
*
* @author Yoko Harada <yokolet@gmail.com>
*/
public class Constant extends AbstractVariable {
private static String pattern = "[A-Z]([a-zA-Z]|_)([a-zA-Z]|_|\\d)*";
private boolean initialized = false;
/**
* Returns an instance of this class. This factory method is used when a constant
* is put in {@link BiVariableMap}.
*
* @param runtime
* @param name a variable name
* @param javaObject Java object that should be assigned to.
* @return the instance of Constant
*/
public static BiVariable getInstance(RubyObject receiver, String name, Object... javaObject) {
if (name.matches(pattern)) {
return new Constant(receiver, name, javaObject);
}
return null;
}
private Constant(RubyObject receiver, String name, Object... javaObjects) {
super(receiver, name, false);
updateByJavaObject(receiver.getRuntime(), javaObjects);
}
/**
* A constructor used when constants are retrieved from Ruby.
*
* @param receiver a receiver object that this variable/constant is originally in. When
* the variable/constant is originated from Ruby, receiver may not be null.
* @param name the constant name
* @param irubyObject Ruby constant object
*/
Constant(IRubyObject receiver, String name, IRubyObject irubyObject) {
super(receiver, name, true, irubyObject);
}
void markInitialized() {
this.initialized = true;
}
/**
* Retrieves constants from Ruby after the evaluation or method invocation.
*
* @param runtime Ruby runtime
* @param receiver receiver object returned when a script is evaluated.
* @param vars map to save retrieved constants.
*/
public static void retrieve(RubyObject receiver, BiVariableMap vars) {
if (vars.isLazy()) return;
// user defined constants of top level go to a super class
updateConstantsOfSuperClass(receiver, vars);
// Constants might have the same names but different receivers.
updateConstants(receiver, vars);
RubyObject topSelf = (RubyObject)receiver.getRuntime().getTopSelf();
updateConstants(topSelf, vars);
}
/*
private static void updateARGV(IRubyObject receiver, BiVariableMap vars) {
String name = "ARGV".intern();
IRubyObject argv = receiver.getRuntime().getTopSelf().getMetaClass().fastGetConstant(name);
if (argv == null || (argv instanceof RubyNil)) return;
BiVariable var; // This var is for ARGV.
// ARGV constant should be only one
if (vars.containsKey((Object)name)) {
var = vars.getVariable((RubyObject)receiver.getRuntime().getTopSelf(), name);
var.setRubyObject(argv);
} else {
var = new Constant(receiver.getRuntime().getTopSelf(), name, argv);
((Constant) var).markInitialized();
vars.update(name, var);
}
}*/
private static void updateConstantsOfSuperClass(RubyObject receiver, BiVariableMap vars) {
// Super class has many many constants, so this method updates only
// constans in BiVariableMap.
Map<String, IRubyObject> map =
receiver.getRuntime().getTopSelf().getMetaClass().getSuperClass().getConstantMap();
List<BiVariable> variables = vars.getVariables();
// Need to check that this constant has been stored in BiVariableMap.
for (BiVariable variable : variables) {
if (variable.getType() == Type.Constant) {
if (map.containsKey(variable.getName())) {
IRubyObject value = map.get(variable.getName());
variable.setRubyObject(value);
}
}
}
}
private static void updateConstants(RubyObject receiver, BiVariableMap vars) {
Collection<String> names = receiver.getMetaClass().getConstantNames();
for (String name : names) {
IRubyObject value = receiver.getMetaClass().getConstant(name);
BiVariable var = null;
List<String> savedNames = vars.getNames();
// Need to check that this constant has been stored in BiVariableMap.
for (int i=0; i<savedNames.size(); i++) {
if (name.equals(savedNames.get(i))) {
var = (BiVariable) vars.getVariables().get(i);
if (receiver == var.getReceiver()) {
var.setRubyObject(value);
} else {
var = null;
}
}
}
if (var == null) {
var = new Constant(receiver, name, value);
((Constant) var).markInitialized();
vars.update(name, var);
}
}
}
/**
* Retrieves a constant by key from Ruby runtime after the evaluation.
* This method is used when eager retrieval is off.
*
* @param receiver receiver object returned when a script is evaluated.
* @param vars map to save retrieved instance variables.
* @param key instace varible name
*/
public static void retrieveByKey(RubyObject receiver, BiVariableMap vars, String key) {
// if the specified key doesn't exist, this method is called before the
// evaluation. Don't update value in this case.
IRubyObject value = null;
if (receiver.getMetaClass().getConstantNames().contains(key)) {
value = receiver.getMetaClass().getConstant(key);
} else if (receiver.getRuntime().getTopSelf().getMetaClass().getConstantNames().contains(key)) {
value = receiver.getRuntime().getTopSelf().getMetaClass().getConstant(key);
} else if (receiver.getRuntime().getTopSelf().getMetaClass().getSuperClass().getConstantNames().contains(key)) {
value = receiver.getRuntime().getTopSelf().getMetaClass().getSuperClass().getConstant(key);
}
if (value == null) return;
// the specified key is found, so let's update
BiVariable var = vars.getVariable(receiver, key);
if (var != null) {
var.setRubyObject(value);
} else {
var = new Constant(receiver, key, value);
vars.update(key, var);
}
}
/**
* Returns enum type of this variable defined in {@link BiVariable}.
*
* @return this enum type, BiVariable.Type.Constant.
*/
public Type getType() {
return Type.Constant;
}
/**
* Returns true if the given name is a decent Ruby constant. Unless
* returns false.
*
* @param name is a name to be checked.
* @return true if the given name is of a Ruby constant.
*/
public static boolean isValidName(Object name) {
return isValidName(pattern, name);
}
/**
* Injects a constant value to a parsed Ruby script. This method is
* invoked during EvalUnit#run() is executed.
*/
public void inject() {
if (receiver == receiver.getRuntime().getTopSelf()) {
RubyModule rubyModule = getRubyClass(receiver.getRuntime());
if (rubyModule == null) rubyModule = receiver.getRuntime().getCurrentContext().getRubyClass();
if (rubyModule == null) return;
rubyModule.storeConstant(name, irubyObject);
receiver.getRuntime().incrementConstantGeneration();
} else {
receiver.getMetaClass().storeConstant(name, irubyObject);
}
initialized = true;
}
/**
* Attempts to remove this constant from top self or receiver.
*
*/
public void remove() {
IRubyObject rubyName = JavaUtil.convertJavaToRuby(receiver.getRuntime(), name);
if (receiver.getMetaClass().getConstantNames().contains(name)) {
receiver.getMetaClass().remove_const(receiver.getRuntime().getCurrentContext(), rubyName);
} else if (receiver.getRuntime().getTopSelf().getMetaClass().getConstantNames().contains(name)) {
receiver.getRuntime().getTopSelf().getMetaClass().remove_const(receiver.getRuntime().getCurrentContext(), rubyName);
} else if (receiver.getRuntime().getTopSelf().getMetaClass().getSuperClass().getConstantNames().contains(name)) {
receiver.getRuntime().getTopSelf().getMetaClass().getSuperClass().remove_const(receiver.getRuntime().getCurrentContext(), rubyName);
}
}
}