1 /*
   2  * Copyright (c) 2015, 2016, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 package jdk.incubator.http.internal.hpack;
  26 
  27 import java.io.IOException;
  28 import java.io.UncheckedIOException;
  29 import java.nio.ByteBuffer;
  30 
  31 //
  32 // Custom implementation of ISO/IEC 8859-1:1998
  33 //
  34 // The rationale behind this is not to deal with CharsetEncoder/CharsetDecoder,
  35 // basically because it would require wrapping every single CharSequence into a
  36 // CharBuffer and then copying it back.
  37 //
  38 // But why not to give a CharBuffer instead of Appendable? Because I can choose
  39 // an Appendable (e.g. StringBuilder) that adjusts its length when needed and
  40 // therefore not to deal with pre-sized CharBuffers or copying.
  41 //
  42 // The encoding is simple and well known: 1 byte <-> 1 char
  43 //
  44 final class ISO_8859_1 {
  45 
  46     private ISO_8859_1() { }
  47 
  48     public static final class Reader {
  49 
  50         public void read(ByteBuffer source, Appendable destination) {
  51             for (int i = 0, len = source.remaining(); i < len; i++) {
  52                 char c = (char) (source.get() & 0xff);
  53                 try {
  54                     destination.append(c);
  55                 } catch (IOException e) {
  56                     throw new UncheckedIOException
  57                             ("Error appending to the destination", e);
  58                 }
  59             }
  60         }
  61 
  62         public Reader reset() {
  63             return this;
  64         }
  65     }
  66 
  67     public static final class Writer {
  68 
  69         private CharSequence source;
  70         private int pos;
  71         private int end;
  72 
  73         public Writer configure(CharSequence source, int start, int end) {
  74             this.source = source;
  75             this.pos = start;
  76             this.end = end;
  77             return this;
  78         }
  79 
  80         public boolean write(ByteBuffer destination) {
  81             for (; pos < end; pos++) {
  82                 char c = source.charAt(pos);
  83                 if (c > '\u00FF') {
  84                     throw new IllegalArgumentException(
  85                             "Illegal ISO-8859-1 char: " + (int) c);
  86                 }
  87                 if (destination.hasRemaining()) {
  88                     destination.put((byte) c);
  89                 } else {
  90                     return false;
  91                 }
  92             }
  93             return true;
  94         }
  95 
  96         public Writer reset() {
  97             source = null;
  98             pos = -1;
  99             end = -1;
 100             return this;
 101         }
 102     }
 103 }