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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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package jdk.internal.util.xml;

import java.io.*;
import java.util.InvalidPropertiesFormatException;
import java.util.Map.Entry;
import java.util.Properties;
import jdk.internal.org.xml.sax.Attributes;
import jdk.internal.org.xml.sax.InputSource;
import jdk.internal.org.xml.sax.SAXException;
import jdk.internal.org.xml.sax.SAXParseException;
import jdk.internal.org.xml.sax.helpers.DefaultHandler;
import jdk.internal.util.xml.impl.SAXParserImpl;
import jdk.internal.util.xml.impl.XMLStreamWriterImpl;

A class used to aid in Properties load and save in XML. This class is re-implemented using a subset of SAX
Author:Joe Wang
Since:1.8
/** * A class used to aid in Properties load and save in XML. This class is * re-implemented using a subset of SAX * * @author Joe Wang * @since 1.8 */
public class PropertiesDefaultHandler extends DefaultHandler { // Elements specified in the properties.dtd private static final String ELEMENT_ROOT = "properties"; private static final String ELEMENT_COMMENT = "comment"; private static final String ELEMENT_ENTRY = "entry"; private static final String ATTR_KEY = "key"; // The required DTD URI for exported properties private static final String PROPS_DTD_DECL = "<!DOCTYPE properties SYSTEM \"http://java.sun.com/dtd/properties.dtd\">"; private static final String PROPS_DTD_URI = "http://java.sun.com/dtd/properties.dtd"; private static final String PROPS_DTD = "<?xml version=\"1.0\" encoding=\"UTF-8\"?>" + "<!-- DTD for properties -->" + "<!ELEMENT properties ( comment?, entry* ) >" + "<!ATTLIST properties" + " version CDATA #FIXED \"1.0\">" + "<!ELEMENT comment (#PCDATA) >" + "<!ELEMENT entry (#PCDATA) >" + "<!ATTLIST entry " + " key CDATA #REQUIRED>";
Version number for the format of exported properties files.
/** * Version number for the format of exported properties files. */
private static final String EXTERNAL_XML_VERSION = "1.0"; private Properties properties; public void load(Properties props, InputStream in) throws IOException, InvalidPropertiesFormatException, UnsupportedEncodingException { this.properties = props; try { SAXParser parser = new SAXParserImpl(); parser.parse(in, this); } catch (SAXException saxe) { throw new InvalidPropertiesFormatException(saxe); } /** * String xmlVersion = propertiesElement.getAttribute("version"); if * (xmlVersion.compareTo(EXTERNAL_XML_VERSION) > 0) throw new * InvalidPropertiesFormatException( "Exported Properties file format * version " + xmlVersion + " is not supported. This java installation * can read" + " versions " + EXTERNAL_XML_VERSION + " or older. You" + * " may need to install a newer version of JDK."); */ } public void store(Properties props, OutputStream os, String comment, String encoding) throws IOException { try { XMLStreamWriter writer = new XMLStreamWriterImpl(os, encoding); writer.writeStartDocument(); writer.writeDTD(PROPS_DTD_DECL); writer.writeStartElement(ELEMENT_ROOT); if (comment != null && comment.length() > 0) { writer.writeStartElement(ELEMENT_COMMENT); writer.writeCharacters(comment); writer.writeEndElement(); } synchronized(props) { for (Entry<Object, Object> e : props.entrySet()) { final Object k = e.getKey(); final Object v = e.getValue(); if (k instanceof String && v instanceof String) { writer.writeStartElement(ELEMENT_ENTRY); writer.writeAttribute(ATTR_KEY, (String)k); writer.writeCharacters((String)v); writer.writeEndElement(); } } } writer.writeEndElement(); writer.writeEndDocument(); writer.flush(); } catch (XMLStreamException e) { if (e.getCause() instanceof UnsupportedEncodingException) { throw (UnsupportedEncodingException) e.getCause(); } throw new IOException(e); } } //////////////////////////////////////////////////////////////////// // Validate while parsing //////////////////////////////////////////////////////////////////// static final String ALLOWED_ELEMENTS = "properties, comment, entry"; static final String ALLOWED_COMMENT = "comment"; //////////////////////////////////////////////////////////////////// // Handler methods //////////////////////////////////////////////////////////////////// StringBuffer buf = new StringBuffer(); boolean sawComment = false; boolean validEntry = false; int rootElem = 0; String key; String rootElm; @Override public void startElement(String uri, String localName, String qName, Attributes attributes) throws SAXException { if (rootElem < 2) { rootElem++; } if (rootElm == null) { fatalError(new SAXParseException("An XML properties document must contain" + " the DOCTYPE declaration as defined by java.util.Properties.", null)); } if (rootElem == 1 && !rootElm.equals(qName)) { fatalError(new SAXParseException("Document root element \"" + qName + "\", must match DOCTYPE root \"" + rootElm + "\"", null)); } if (!ALLOWED_ELEMENTS.contains(qName)) { fatalError(new SAXParseException("Element type \"" + qName + "\" must be declared.", null)); } if (qName.equals(ELEMENT_ENTRY)) { validEntry = true; key = attributes.getValue(ATTR_KEY); if (key == null) { fatalError(new SAXParseException("Attribute \"key\" is required and must be specified for element type \"entry\"", null)); } } else if (qName.equals(ALLOWED_COMMENT)) { if (sawComment) { fatalError(new SAXParseException("Only one comment element may be allowed. " + "The content of element type \"properties\" must match \"(comment?,entry*)\"", null)); } sawComment = true; } } @Override public void characters(char[] ch, int start, int length) throws SAXException { if (validEntry) { buf.append(ch, start, length); } } @Override public void endElement(String uri, String localName, String qName) throws SAXException { if (!ALLOWED_ELEMENTS.contains(qName)) { fatalError(new SAXParseException("Element: " + qName + " is invalid, must match \"(comment?,entry*)\".", null)); } if (validEntry) { properties.setProperty(key, buf.toString()); buf.delete(0, buf.length()); validEntry = false; } } @Override public void notationDecl(String name, String publicId, String systemId) throws SAXException { rootElm = name; } @Override public InputSource resolveEntity(String pubid, String sysid) throws SAXException, IOException { { if (sysid.equals(PROPS_DTD_URI)) { InputSource is; is = new InputSource(new StringReader(PROPS_DTD)); is.setSystemId(PROPS_DTD_URI); return is; } throw new SAXException("Invalid system identifier: " + sysid); } } @Override public void error(SAXParseException x) throws SAXException { throw x; } @Override public void fatalError(SAXParseException x) throws SAXException { throw x; } @Override public void warning(SAXParseException x) throws SAXException { throw x; } }