| /* ==================================================================== |
| Licensed to the Apache Software Foundation (ASF) under one or more |
| contributor license agreements. See the NOTICE file distributed with |
| this work for additional information regarding copyright ownership. |
| The ASF licenses this file to You 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.poi.openxml4j.opc; |
| |
| import java.io.FilterOutputStream; |
| import java.io.IOException; |
| import java.io.InputStream; |
| import java.io.OutputStream; |
| |
| import javax.xml.transform.OutputKeys; |
| import javax.xml.transform.Result; |
| import javax.xml.transform.Source; |
| import javax.xml.transform.Transformer; |
| import javax.xml.transform.TransformerException; |
| import javax.xml.transform.TransformerFactory; |
| import javax.xml.transform.dom.DOMSource; |
| import javax.xml.transform.stream.StreamResult; |
| |
| import org.w3c.dom.Document; |
| |
| public final class StreamHelper { |
| |
| private StreamHelper() { |
| // Do nothing |
| } |
| |
| private static final TransformerFactory transformerFactory = TransformerFactory.newInstance(); |
| |
| private static synchronized Transformer getIdentityTransformer() throws TransformerException { |
| return transformerFactory.newTransformer(); |
| } |
| |
| /** |
| * Save the document object in the specified output stream. |
| * |
| * @param xmlContent |
| * The XML document. |
| * @param outStream |
| * The OutputStream in which the XML document will be written. |
| * @return <b>true</b> if the xml is successfully written in the stream, |
| * else <b>false</b>. |
| */ |
| public static boolean saveXmlInStream(Document xmlContent, |
| OutputStream outStream) { |
| try { |
| Transformer trans = getIdentityTransformer(); |
| Source xmlSource = new DOMSource(xmlContent); |
| // prevent close of stream by transformer: |
| Result outputTarget = new StreamResult(new FilterOutputStream( |
| outStream) { |
| @Override |
| public void write(byte b[], int off, int len) |
| throws IOException { |
| out.write(b, off, len); |
| } |
| |
| @Override |
| public void close() throws IOException { |
| out.flush(); // only flush, don't close! |
| } |
| }); |
| trans.setOutputProperty(OutputKeys.ENCODING, "UTF-8"); |
| trans.setOutputProperty(OutputKeys.INDENT, "yes"); |
| trans.setOutputProperty(OutputKeys.STANDALONE, "yes"); |
| trans.transform(xmlSource, outputTarget); |
| } catch (TransformerException e) { |
| return false; |
| } |
| return true; |
| } |
| |
| /** |
| * Copy the input stream into the output stream. |
| * |
| * @param inStream |
| * The source stream. |
| * @param outStream |
| * The destination stream. |
| * @return <b>true</b> if the operation succeed, else return <b>false</b>. |
| */ |
| public static boolean copyStream(InputStream inStream, OutputStream outStream) { |
| try { |
| byte[] buffer = new byte[1024]; |
| int bytesRead; |
| while ((bytesRead = inStream.read(buffer)) >= 0) { |
| outStream.write(buffer, 0, bytesRead); |
| } |
| } catch (Exception e) { |
| return false; |
| } |
| return true; |
| } |
| } |