/**
* **** 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.Set;
import org.jruby.Ruby;
import org.jruby.RubyObject;
import org.jruby.internal.runtime.GlobalVariables;
import org.jruby.runtime.builtin.IRubyObject;
/**
* An implementation of BiVariable for a Ruby global variable.
*
* @author Yoko Harada <yokolet@gmail.com>
*/
public class GlobalVariable extends AbstractVariable {
private static String pattern = "\\$(([a-zA-Z]|_|\\d)*|-[a-zA-Z]|[!-~&&[^#%()-\\{\\}\\[\\]\\|\\^]])";
/**
* Returns an instance of this class. This factory method is used when a global
* 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 GlobalVariable
*/
public static BiVariable getInstance(RubyObject receiver, String name, Object... javaObject) {
if (name.matches(pattern)) {
GlobalVariable gvar = new GlobalVariable(receiver, name, javaObject);
gvar.tryEagerInjection(receiver.getRuntime(), null);
return gvar;
}
return null;
}
protected GlobalVariable(RubyObject receiver, String name, Object... javaObjects) {
super(receiver, name, false);
updateByJavaObject(receiver.getRuntime(), javaObjects);
}
/**
* A constructor used when global variables are retrieved from Ruby.
*
* @param name the global variable name
* @param irubyObject Ruby global object
*/
GlobalVariable(IRubyObject receiver, String name, IRubyObject irubyObject) {
super(receiver, name, true, irubyObject);
}
/**
* Retrieves global variables from Ruby after the evaluation.
*
* @param runtime Ruby runtime
* @param receiver receiver object returned when a script is evaluated.
* @param vars map to save retrieved global variables.
*/
public static void retrieve(IRubyObject 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);
// reciever of gvar should to topSelf always
updateGlobalVar(vars, (RubyObject)receiver.getRuntime().getTopSelf(), name, value);
}
}
private static void updateGlobalVar(BiVariableMap vars, RubyObject receiver, String name, IRubyObject value) {
BiVariable var;
if (vars.containsKey((Object) name)) {
var = vars.getVariable(receiver, name);
var.setRubyObject(value);
} else {
var = new GlobalVariable(receiver, name, value);
vars.update(name, var);
}
}
/**
* Retrieves a global variable by key from Ruby after the evaluation.
*
* @param runtime Ruby runtime
* @param receiver receiver object returned when a script is evaluated.
* @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.
if (!gvars.getNames().contains(key)) return;
// the specified key is found, so let's update
IRubyObject value = gvars.get(key);
updateGlobalVar(vars, (RubyObject)runtime.getTopSelf(), key, value);
}
protected static boolean isPredefined(String name) {
String[] patterns = {
"\\$([\\u0021-\\u0040]|\\u005c|[\\u005e-\\u0060]|\\u007e)",
"\\$-(\\d|[A-z])",
"\\$(DEBUG|F|FILENAME|KCODE|LOAD_PATH|SAFE|VERBOSE|CLASSPATH|LOADED_FEATURES|PROGRAM_NAME)",
"\\$(configure_args|deferr|defout|expect_verbose|stderr|stdin|stdout)"
};
for (String p : patterns) {
if (name.matches(p)) {
return true;
}
}
return false;
}
/**
* Returns enum type of this variable defined in {@link BiVariable}.
*
* @return this enum type, BiVariable.Type.GlobalVariable.
*/
public Type getType() {
return Type.GlobalVariable;
}
/**
* Returns true if the given name is a decent Ruby global variable. Unless
* returns false.
*
* @param name is a name to be checked.
* @return true if the given name is of a Ruby global variable.
*/
public static boolean isValidName(Object name) {
return isValidName(pattern, name);
}
/**
* Sets a Java object and its Ruby type as a value of this object.
* At the same time, sets Ruby object to Ruby runtime.
*
* @param runtime is used to convert a Java object to Ruby object.
* @param javaObject is a variable value to be set.
*/
public void setJavaObject(Ruby runtime, Object javaObject) {
updateByJavaObject(runtime, javaObject);
tryEagerInjection(runtime, null);
}
/**
* A global variable is injected when it is set. This method does nothing.
* Instead injection is done by tryEagerInjection.
*/
public void inject() {
// do nothing
}
/**
* Injects a global variable value to a parsed Ruby script. This method is
* invoked during EvalUnit#run() is executed.
*
* @param runtime is environment where a variable injection occurs
* @param receiver is the instance that will have variable injection.
*/
public void tryEagerInjection(Ruby runtime, IRubyObject receiver) {
// wreckages of global local vars might remain on runtime, which may cause
// assertion error since those names doesn't start from "$"
name = name.startsWith("$") ? name : ("$" + name).intern();
runtime.getGlobalVariables().set(name, irubyObject);
}
/**
* Attempts to remove this variable from top self or receiver.
*
*/
public void remove() {
receiver.getRuntime().getGlobalVariables().clear(name);
}
/**
* Returns true if a given receiver is identical to the receiver this object has.
*
* @return true always
*/
@Override
public boolean isReceiverIdentical(RubyObject recv) {
return true;
}
}