org.jruby.embed.internal.EmbedRubyInterfaceAdapterImpl Maven / Gradle / Ivy
/**
* **** 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 Yoko Harada
*
* 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.internal;
import java.io.IOException;
import java.io.PrintWriter;
import java.io.Writer;
import org.jruby.Ruby;
import org.jruby.RubyNil;
import org.jruby.embed.EmbedRubyInterfaceAdapter;
import org.jruby.embed.InvokeFailedException;
import org.jruby.embed.ScriptingContainer;
import org.jruby.javasupport.JavaEmbedUtils;
import org.jruby.javasupport.JavaUtil;
import org.jruby.runtime.builtin.IRubyObject;
/**
* The implementation of {@link EmbedRubyInterfaceAdapter} and implements the
* method that gets a instance of requested interface, which is implemented in Ruby.
*
* @author Yoko Harada
*/
public class EmbedRubyInterfaceAdapterImpl implements EmbedRubyInterfaceAdapter {
private ScriptingContainer container;
public EmbedRubyInterfaceAdapterImpl(ScriptingContainer container) {
this.container = container;
}
/**
* Returns a instance of a requested interface type from a previously evaluated script.
*
* @param receiver a receiver of the previously evaluated script.
* @param clazz an interface type of the returning instance.
* @return an instance of requested interface type.
*/
public T getInstance(Object receiver, Class clazz) {
if (clazz == null || !clazz.isInterface()) {
return null;
}
Ruby runtime = container.getProvider().getRuntime();
Object o;
if (receiver == null || receiver instanceof RubyNil) {
o = JavaEmbedUtils.rubyToJava(runtime, runtime.getTopSelf(), clazz);
} else if (receiver instanceof IRubyObject) {
o = JavaEmbedUtils.rubyToJava(runtime, (IRubyObject) receiver, clazz);
} else {
IRubyObject rubyReceiver = JavaUtil.convertJavaToRuby(runtime, receiver);
o = JavaEmbedUtils.rubyToJava(runtime, rubyReceiver, clazz);
}
String name = clazz.getName();
try {
Class c = (Class) Class.forName(name, true, o.getClass().getClassLoader());
return c.cast(o);
} catch (ClassNotFoundException e) {
Writer w = container.getErrorWriter();
if (w instanceof PrintWriter) {
e.printStackTrace((PrintWriter)w);
} else {
try {
w.write(e.getMessage());
} catch (IOException ex) {
throw new InvokeFailedException(ex);
}
}
throw new InvokeFailedException(e);
}
}
}