| /* Copyright 2004 The Apache Software Foundation |
| * |
| * Licensed under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package org.apache.xmlbeans.impl.common; |
| |
| import java.io.IOException; |
| import java.io.Reader; |
| import java.io.BufferedReader; |
| import java.nio.charset.Charset; |
| |
| public class SniffedXmlReader extends BufferedReader |
| { |
| // We don't sniff more than 192 bytes. |
| public static int MAX_SNIFFED_CHARS = 192; |
| |
| public SniffedXmlReader(Reader reader) throws IOException |
| { |
| super(reader); |
| _encoding = sniffForXmlDecl(); |
| } |
| |
| private int readAsMuchAsPossible(char[] buf, int startAt, int len) throws IOException |
| { |
| int total = 0; |
| while (total < len) |
| { |
| int count = read(buf, startAt + total, len - total); |
| if (count < 0) |
| break; |
| total += count; |
| } |
| return total; |
| } |
| |
| // BUGBUG in JDK: Charset.forName is not threadsafe, so we'll prime it |
| // with the common charsets. |
| |
| private static Charset dummy1 = Charset.forName("UTF-8"); |
| private static Charset dummy2 = Charset.forName("UTF-16"); |
| private static Charset dummy3 = Charset.forName("UTF-16BE"); |
| private static Charset dummy4 = Charset.forName("UTF-16LE"); |
| private static Charset dummy5 = Charset.forName("ISO-8859-1"); |
| private static Charset dummy6 = Charset.forName("US-ASCII"); |
| private static Charset dummy7 = Charset.forName("Cp1252"); |
| |
| |
| private String sniffForXmlDecl() throws IOException |
| { |
| mark(MAX_SNIFFED_CHARS); |
| try |
| { |
| char[] buf = new char[MAX_SNIFFED_CHARS]; |
| int limit = readAsMuchAsPossible(buf, 0, MAX_SNIFFED_CHARS); |
| return SniffedXmlInputStream.extractXmlDeclEncoding(buf, 0, limit); |
| } |
| finally |
| { |
| reset(); |
| } |
| } |
| |
| private String _encoding; |
| |
| public String getXmlEncoding() |
| { |
| return _encoding; |
| } |
| } |