rt/vm/src/test/java/org/apidesign/vm4brwsr/BytesLoader.java
author Jaroslav Tulach <jaroslav.tulach@apidesign.org>
Fri, 27 Feb 2015 18:11:54 +0100
changeset 1798 18b3a9a85716
parent 1787 ea12a3bb4b33
permissions -rw-r--r--
addIfMissing to iterate over the array just once
     1 /**
     2  * Back 2 Browser Bytecode Translator
     3  * Copyright (C) 2012-2015 Jaroslav Tulach <jaroslav.tulach@apidesign.org>
     4  *
     5  * This program is free software: you can redistribute it and/or modify
     6  * it under the terms of the GNU General Public License as published by
     7  * the Free Software Foundation, version 2 of the License.
     8  *
     9  * This program is distributed in the hope that it will be useful,
    10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
    11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    12  * GNU General Public License for more details.
    13  *
    14  * You should have received a copy of the GNU General Public License
    15  * along with this program. Look for COPYING file in the top folder.
    16  * If not, see http://opensource.org/licenses/GPL-2.0.
    17  */
    18 package org.apidesign.vm4brwsr;
    19 
    20 import java.io.IOException;
    21 import java.io.InputStream;
    22 import java.net.URL;
    23 import java.util.Enumeration;
    24 
    25 /**
    26  *
    27  * @author Jaroslav Tulach <jtulach@netbeans.org>
    28  */
    29 public final class BytesLoader {
    30     private static final StringArray requested = new StringArray();
    31 
    32     public byte[] get(String name) throws IOException {
    33         if (!requested.addIfMissing(name)) {
    34             throw new IllegalStateException("Requested for second time: " + name);
    35         }
    36         byte[] arr = readClass(name);
    37         /*
    38         System.err.print("loader['" + name + "'] = [");
    39         for (int i = 0; i < arr.length; i++) {
    40         if (i > 0) {
    41         System.err.print(", ");
    42         }
    43         System.err.print(arr[i]);
    44         }
    45         System.err.println("]");
    46          */
    47         return arr;
    48     }
    49 
    50     static byte[] readClass(String name) throws IOException {
    51         URL u = null;
    52         Enumeration<URL> en = BytesLoader.class.getClassLoader().getResources(name);
    53         while (en.hasMoreElements()) {
    54             u = en.nextElement();
    55         }
    56         if (u == null) {
    57             throw new IOException("Can't find " + name);
    58         }
    59         try (InputStream is = u.openStream()) {
    60             byte[] arr;
    61             arr = new byte[is.available()];
    62             int offset = 0;
    63             while (offset < arr.length) {
    64                 int len = is.read(arr, offset, arr.length - offset);
    65                 if (len == -1) {
    66                     throw new IOException("Can't read " + name);
    67                 }
    68                 offset += len;
    69             }
    70             return arr;
    71         }
    72     }
    73     
    74 }