jaroslav@298: /**
jaroslav@298:  * Back 2 Browser Bytecode Translator
jaroslav@298:  * Copyright (C) 2012 Jaroslav Tulach <jaroslav.tulach@apidesign.org>
jaroslav@298:  *
jaroslav@298:  * This program is free software: you can redistribute it and/or modify
jaroslav@298:  * it under the terms of the GNU General Public License as published by
jaroslav@298:  * the Free Software Foundation, version 2 of the License.
jaroslav@298:  *
jaroslav@298:  * This program is distributed in the hope that it will be useful,
jaroslav@298:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
jaroslav@298:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
jaroslav@298:  * GNU General Public License for more details.
jaroslav@298:  *
jaroslav@298:  * You should have received a copy of the GNU General Public License
jaroslav@298:  * along with this program. Look for COPYING file in the top folder.
jaroslav@298:  * If not, see http://opensource.org/licenses/GPL-2.0.
jaroslav@298:  */
jaroslav@298: package org.apidesign.vm4brwsr;
jaroslav@298: 
jaroslav@298: import java.io.IOException;
jaroslav@298: import java.io.InputStream;
jaroslav@336: import java.net.URL;
jaroslav@336: import java.util.Enumeration;
jaroslav@298: import java.util.Set;
jaroslav@298: import java.util.TreeSet;
jaroslav@298: 
jaroslav@298: /**
jaroslav@298:  *
jaroslav@298:  * @author Jaroslav Tulach <jtulach@netbeans.org>
jaroslav@298:  */
jaroslav@298: public final class BytesLoader {
jaroslav@298:     private static Set<String> requested = new TreeSet<String>();
jaroslav@298: 
jaroslav@298:     public byte[] get(String name) throws IOException {
jaroslav@298:         if (!requested.add(name)) {
jaroslav@298:             throw new IllegalStateException("Requested for second time: " + name);
jaroslav@298:         }
jaroslav@334:         byte[] arr = readClass(name);
jaroslav@334:         /*
jaroslav@334:         System.err.print("loader['" + name + "'] = [");
jaroslav@334:         for (int i = 0; i < arr.length; i++) {
jaroslav@334:         if (i > 0) {
jaroslav@334:         System.err.print(", ");
jaroslav@334:         }
jaroslav@334:         System.err.print(arr[i]);
jaroslav@334:         }
jaroslav@334:         System.err.println("]");
jaroslav@334:          */
jaroslav@334:         return arr;
jaroslav@334:     }
jaroslav@334: 
jaroslav@334:     static byte[] readClass(String name) throws IOException {
jaroslav@336:         URL u = null;
jaroslav@336:         Enumeration<URL> en = BytesLoader.class.getClassLoader().getResources(name);
jaroslav@336:         while (en.hasMoreElements()) {
jaroslav@336:             u = en.nextElement();
jaroslav@336:         }
jaroslav@336:         if (u == null) {
jaroslav@298:             throw new IOException("Can't find " + name);
jaroslav@298:         }
jaroslav@336:         try (InputStream is = u.openStream()) {
jaroslav@336:             byte[] arr;
jaroslav@336:             arr = new byte[is.available()];
jaroslav@336:             int offset = 0;
jaroslav@336:             while (offset < arr.length) {
jaroslav@336:                 int len = is.read(arr, offset, arr.length - offset);
jaroslav@336:                 if (len == -1) {
jaroslav@336:                     throw new IOException("Can't read " + name);
jaroslav@336:                 }
jaroslav@336:                 offset += len;
jaroslav@325:             }
jaroslav@336:             return arr;
jaroslav@298:         }
jaroslav@298:     }
jaroslav@298:     
jaroslav@298: }