1 /*
   2  * Copyright (c) 2012, 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 
  26 package jdk.internal.util.xml.impl;
  27 
  28 import java.io.BufferedOutputStream;
  29 import java.io.IOException;
  30 import java.io.OutputStream;
  31 import java.io.OutputStreamWriter;
  32 import java.io.UnsupportedEncodingException;
  33 import java.io.Writer;
  34 import java.nio.charset.Charset;
  35 import java.nio.charset.CharsetEncoder;
  36 import jdk.internal.util.xml.XMLStreamException;
  37 
  38 /**
  39  *
  40  * @author huizwang
  41  */
  42 public class XMLWriter {
  43 
  44     private Writer _writer;
  45     /**
  46      * In some cases, this charset encoder is used to determine if a char is
  47      * encodable by underlying writer. For example, an 8-bit char from the
  48      * extended ASCII set is not encodable by 7-bit ASCII encoder. Unencodable
  49      * chars are escaped using XML numeric entities.
  50      */
  51     private CharsetEncoder _encoder = null;
  52 
  53     public XMLWriter(OutputStream os, String encoding, Charset cs) throws XMLStreamException {
  54         _encoder = cs.newEncoder();
  55         try {
  56             _writer = getWriter(os, encoding, cs);
  57         } catch (UnsupportedEncodingException ex) {
  58             throw new XMLStreamException(ex);
  59         }
  60 
  61     }
  62 
  63     public boolean canEncode(char ch) {
  64         if (_encoder == null) {
  65             return false;
  66         }
  67         return (_encoder.canEncode(ch));
  68     }
  69 
  70     public void write(String s)
  71             throws XMLStreamException {
  72         try {
  73             _writer.write(s.toCharArray());
  74 //            _writer.write(s.getBytes(Charset.forName(_encoding)));
  75         } catch (IOException e) {
  76             throw new XMLStreamException("I/O error", e);
  77         }
  78     }
  79 
  80     public void write(String str, int off, int len)
  81             throws XMLStreamException {
  82         try {
  83             _writer.write(str, off, len);
  84         } catch (IOException e) {
  85             throw new XMLStreamException("I/O error", e);
  86         }
  87 
  88     }
  89 
  90     public void write(char[] cbuf, int off, int len)
  91             throws XMLStreamException {
  92         try {
  93             _writer.write(cbuf, off, len);
  94         } catch (IOException e) {
  95             throw new XMLStreamException("I/O error", e);
  96         }
  97 
  98     }
  99 
 100     void write(int b)
 101             throws XMLStreamException {
 102         try {
 103             _writer.write(b);
 104         } catch (IOException e) {
 105             throw new XMLStreamException("I/O error", e);
 106         }
 107     }
 108 
 109     void flush() throws XMLStreamException {
 110         try {
 111             _writer.flush();
 112         } catch (IOException ex) {
 113             throw new XMLStreamException(ex);
 114         }
 115     }
 116 
 117     void close() throws XMLStreamException {
 118         try {
 119             _writer.close();
 120         } catch (IOException ex) {
 121             throw new XMLStreamException(ex);
 122         }
 123     }
 124 
 125     private void nl() throws XMLStreamException {
 126         String lineEnd = System.getProperty("line.separator");
 127         try {
 128             _writer.write(lineEnd);
 129         } catch (IOException e) {
 130             throw new XMLStreamException("I/O error", e);
 131         }
 132     }
 133 
 134     /**
 135      * Returns a writer for the specified encoding based on an output stream.
 136      *
 137      * @param output The output stream
 138      * @param encoding The encoding
 139      * @return A suitable writer
 140      * @throws UnsupportedEncodingException There is no convertor to support
 141      * this encoding
 142      */
 143     private Writer getWriter(OutputStream output, String encoding, Charset cs)
 144         throws XMLStreamException, UnsupportedEncodingException 
 145     {
 146         if (cs != null) {
 147             return (new OutputStreamWriter(new BufferedOutputStream(output), cs));
 148         }
 149 
 150         return new OutputStreamWriter(new BufferedOutputStream(output), encoding);
 151     }
 152 }