Java tutorial
/* * Copyright 2014 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 com.ackpdfbox.app.imageio; import java.io.StringWriter; import javax.imageio.metadata.IIOMetadata; import javax.imageio.metadata.IIOMetadataNode; import javax.xml.transform.OutputKeys; 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.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; /** * * @author Tilman Hausherr */ public final class MetaUtil { private static final Log LOG = LogFactory.getLog(MetaUtil.class); static final String SUN_TIFF_FORMAT = "com_sun_media_imageio_plugins_tiff_image_1.0"; static final String JPEG_NATIVE_FORMAT = "javax_imageio_jpeg_image_1.0"; static final String STANDARD_METADATA_FORMAT = "javax_imageio_1.0"; private MetaUtil() { } // logs metadata as an XML tree if debug is enabled static void debugLogMetadata(IIOMetadata metadata, String format) { if (!LOG.isDebugEnabled()) { return; } // see http://docs.oracle.com/javase/7/docs/api/javax/imageio/ // metadata/doc-files/standard_metadata.html IIOMetadataNode root = (IIOMetadataNode) metadata.getAsTree(format); try { StringWriter xmlStringWriter = new StringWriter(); StreamResult streamResult = new StreamResult(xmlStringWriter); Transformer transformer = TransformerFactory.newInstance().newTransformer(); // see http://stackoverflow.com/a/1264872/535646 transformer.setOutputProperty(OutputKeys.INDENT, "yes"); transformer.setOutputProperty("{http://xml.apache.org/xslt}indent-amount", "2"); DOMSource domSource = new DOMSource(root); transformer.transform(domSource, streamResult); LOG.debug("\n" + xmlStringWriter); } catch (IllegalArgumentException ex) { LOG.error(ex, ex); } catch (TransformerException ex) { LOG.error(ex, ex); } } }