Java tutorial
/******************************************************************************* * Copyright (c) 2000, 2013 IBM Corporation and others. * All rights reserved. This program and the accompanying materials * are made available under the terms of the Eclipse Public License v1.0 * which accompanies this distribution, and is available at * http://www.eclipse.org/legal/epl-v10.html * * Contributors: * IBM Corporation - initial API and implementation * Marc R. Hoffmann <hoffmann@mountainminds.com> - Bug 284265 [JFace] * DialogSettings.save() silently ignores IOException * Ruediger Herrmann <ruediger.herrmann@gmx.de> - bug 92518 *******************************************************************************/ package org.eclipse.jface.dialogs; import org.w3c.dom.Document; import org.w3c.dom.Element; import org.w3c.dom.Node; import org.w3c.dom.NodeList; import org.xml.sax.InputSource; import org.xml.sax.SAXException; import javax.xml.parsers.DocumentBuilder; import javax.xml.parsers.DocumentBuilderFactory; import javax.xml.parsers.ParserConfigurationException; import java.io.BufferedReader; import java.io.BufferedWriter; import java.io.FileInputStream; import java.io.FileOutputStream; import java.io.IOException; import java.io.InputStreamReader; import java.io.OutputStream; import java.io.OutputStreamWriter; import java.io.Reader; import java.io.Writer; import java.util.ArrayList; import java.util.Collection; import java.util.Collections; import java.util.Enumeration; import java.util.HashMap; import java.util.Iterator; import java.util.List; import java.util.Map; /** * Concrete implementation of a dialog settings (<code>IDialogSettings</code>) * using a hash table and XML. The dialog store can be read * from and saved to a stream. All keys and values must be strings or array of * strings. Primitive types are converted to strings. * <p> * This class was not designed to be subclassed. * * Here is an example of using a DialogSettings: * </p> * <pre> * <code> * DialogSettings settings = new DialogSettings("root"); * settings.put("Boolean1",true); * settings.put("Long1",100); * settings.put("Array1",new String[]{"aaaa1","bbbb1","cccc1"}); * DialogSettings section = new DialogSettings("sectionName"); * settings.addSection(section); * section.put("Int2",200); * section.put("Float2",1.1); * section.put("Array2",new String[]{"aaaa2","bbbb2","cccc2"}); * settings.save("c:\\temp\\test\\dialog.xml"); * </code> * </pre> * @noextend This class is not intended to be subclassed by clients. */ public class DialogSettings implements IDialogSettings { // The name of the DialogSettings. private String name; /* A Map of DialogSettings representing each sections in a DialogSettings. It maps the DialogSettings' name to the DialogSettings */ private Map<String, IDialogSettings> sections; /* A Map with all the keys and values of this sections. Either the keys an values are restricted to strings. */ private Map<String, String> items; // A Map with all the keys mapped to array of strings. private Map<String, String[]> arrayItems; private static final String TAG_SECTION = "section";//$NON-NLS-1$ private static final String TAG_NAME = "name";//$NON-NLS-1$ private static final String TAG_KEY = "key";//$NON-NLS-1$ private static final String TAG_VALUE = "value";//$NON-NLS-1$ private static final String TAG_LIST = "list";//$NON-NLS-1$ private static final String TAG_ITEM = "item";//$NON-NLS-1$ /** * Create an empty dialog settings which loads and saves its * content to a file. * Use the methods <code>load(String)</code> and <code>store(String)</code> * to load and store this dialog settings. * * @param sectionName the name of the section in the settings. */ public DialogSettings(String sectionName) { name = sectionName; items = new HashMap<String, String>(); arrayItems = new HashMap<String, String[]>(); sections = new HashMap<String, IDialogSettings>(); } /* (non-Javadoc) * Method declared on IDialogSettings. */ @Override public IDialogSettings addNewSection(String sectionName) { DialogSettings section = new DialogSettings(sectionName); addSection(section); return section; } /* (non-Javadoc) * Method declared on IDialogSettings. */ @Override public void addSection(IDialogSettings section) { sections.put(section.getName(), section); } /** * Remove a section in the receiver. If the given section does not exist, * nothing is done. * * @param section * the section to be removed. Must not be <code>null</code>. * @since 3.9 */ public void removeSection(IDialogSettings section) { if (sections.get(section.getName()) == section) { sections.remove(section.getName()); } } /** * Remove a section by name in the receiver. If the given section does not * exist, nothing is done. * * @param sectionName * the name of the section to be removed. Must not be <code>null</code>. * @return The dialog section removed, or <code>null</code> if it wasn't there. * @since 3.9 */ public IDialogSettings removeSection(String sectionName) { return sections.remove(sectionName); } /* (non-Javadoc) * Method declared on IDialogSettings. */ @Override public String get(String key) { return items.get(key); } /* (non-Javadoc) * Method declared on IDialogSettings. */ @Override public String[] getArray(String key) { return arrayItems.get(key); } /* (non-Javadoc) * Method declared on IDialogSettings. */ @Override public boolean getBoolean(String key) { return Boolean.valueOf(items.get(key)).booleanValue(); } /* (non-Javadoc) * Method declared on IDialogSettings. */ @Override public double getDouble(String key) throws NumberFormatException { String setting = items.get(key); if (setting == null) { throw new NumberFormatException("There is no setting associated with the key \"" + key + "\"");//$NON-NLS-1$ //$NON-NLS-2$ } return new Double(setting).doubleValue(); } /* (non-Javadoc) * Method declared on IDialogSettings. */ @Override public float getFloat(String key) throws NumberFormatException { String setting = items.get(key); if (setting == null) { throw new NumberFormatException("There is no setting associated with the key \"" + key + "\"");//$NON-NLS-1$ //$NON-NLS-2$ } return new Float(setting).floatValue(); } /* (non-Javadoc) * Method declared on IDialogSettings. */ @Override public int getInt(String key) throws NumberFormatException { String setting = items.get(key); if (setting == null) { //new Integer(null) will throw a NumberFormatException and meet our spec, but this message //is clearer. throw new NumberFormatException("There is no setting associated with the key \"" + key + "\"");//$NON-NLS-1$ //$NON-NLS-2$ } return new Integer(setting).intValue(); } /* (non-Javadoc) * Method declared on IDialogSettings. */ @Override public long getLong(String key) throws NumberFormatException { String setting = items.get(key); if (setting == null) { //new Long(null) will throw a NumberFormatException and meet our spec, but this message //is clearer. throw new NumberFormatException("There is no setting associated with the key \"" + key + "\"");//$NON-NLS-1$ //$NON-NLS-2$ } return new Long(setting).longValue(); } /* (non-Javadoc) * Method declared on IDialogSettings. */ @Override public String getName() { return name; } /** * Returns a section with the given name in the given dialog settings. If * the section doesn't exist yet, then it is first created. * * @param settings * the parent settings * @param sectionName * the name of the section * @return the section * * @since 3.7 */ public static IDialogSettings getOrCreateSection(IDialogSettings settings, String sectionName) { IDialogSettings section = settings.getSection(sectionName); if (section == null) { section = settings.addNewSection(sectionName); } return section; } /* (non-Javadoc) * Method declared on IDialogSettings. */ @Override public IDialogSettings getSection(String sectionName) { return sections.get(sectionName); } /* (non-Javadoc) * Method declared on IDialogSettings. */ @Override public IDialogSettings[] getSections() { Collection<IDialogSettings> values = sections.values(); DialogSettings[] result = new DialogSettings[values.size()]; values.toArray(result); return result; } /* (non-Javadoc) * Method declared on IDialogSettings. */ @Override public void load(Reader r) { Document document = null; try { DocumentBuilder parser = DocumentBuilderFactory.newInstance().newDocumentBuilder(); // parser.setProcessNamespace(true); document = parser.parse(new InputSource(r)); //Strip out any comments first Node root = document.getFirstChild(); while (root.getNodeType() == Node.COMMENT_NODE) { document.removeChild(root); root = document.getFirstChild(); } load(document, (Element) root); } catch (ParserConfigurationException e) { // ignore } catch (IOException e) { // ignore } catch (SAXException e) { // ignore } } /* (non-Javadoc) * Method declared on IDialogSettings. */ @Override public void load(String fileName) throws IOException { FileInputStream stream = new FileInputStream(fileName); BufferedReader reader = new BufferedReader(new InputStreamReader(stream, "utf-8"));//$NON-NLS-1$ load(reader); reader.close(); } /* (non-Javadoc) * Load the setting from the <code>document</code> */ private void load(Document document, Element root) { name = root.getAttribute(TAG_NAME); NodeList l = root.getElementsByTagName(TAG_ITEM); for (int i = 0; i < l.getLength(); i++) { Node n = l.item(i); if (root == n.getParentNode()) { String key = ((Element) l.item(i)).getAttribute(TAG_KEY); String value = ((Element) l.item(i)).getAttribute(TAG_VALUE); items.put(key, value); } } l = root.getElementsByTagName(TAG_LIST); for (int i = 0; i < l.getLength(); i++) { Node n = l.item(i); if (root == n.getParentNode()) { Element child = (Element) l.item(i); String key = child.getAttribute(TAG_KEY); NodeList list = child.getElementsByTagName(TAG_ITEM); List<String> valueList = new ArrayList<String>(); for (int j = 0; j < list.getLength(); j++) { Element node = (Element) list.item(j); if (child == node.getParentNode()) { valueList.add(node.getAttribute(TAG_VALUE)); } } String[] value = new String[valueList.size()]; valueList.toArray(value); arrayItems.put(key, value); } } l = root.getElementsByTagName(TAG_SECTION); for (int i = 0; i < l.getLength(); i++) { Node n = l.item(i); if (root == n.getParentNode()) { DialogSettings s = new DialogSettings("NoName");//$NON-NLS-1$ s.load(document, (Element) n); addSection(s); } } } /* (non-Javadoc) * Method declared on IDialogSettings. */ @Override public void put(String key, String[] value) { arrayItems.put(key, value); } /* (non-Javadoc) * Method declared on IDialogSettings. */ @Override public void put(String key, double value) { put(key, String.valueOf(value)); } /* (non-Javadoc) * Method declared on IDialogSettings. */ @Override public void put(String key, float value) { put(key, String.valueOf(value)); } /* (non-Javadoc) * Method declared on IDialogSettings. */ @Override public void put(String key, int value) { put(key, String.valueOf(value)); } /* (non-Javadoc) * Method declared on IDialogSettings. */ @Override public void put(String key, long value) { put(key, String.valueOf(value)); } /* (non-Javadoc) * Method declared on IDialogSettings. */ @Override public void put(String key, String value) { items.put(key, value); } /* (non-Javadoc) * Method declared on IDialogSettings. */ @Override public void put(String key, boolean value) { put(key, String.valueOf(value)); } /* (non-Javadoc) * Method declared on IDialogSettings. */ @Override public void save(Writer writer) throws IOException { final XMLWriter xmlWriter = new XMLWriter(writer); save(xmlWriter); xmlWriter.flush(); } /* (non-Javadoc) * Method declared on IDialogSettings. */ @Override public void save(String fileName) throws IOException { FileOutputStream stream = new FileOutputStream(fileName); XMLWriter writer = new XMLWriter(stream); save(writer); writer.close(); } /* (non-Javadoc) * Save the settings in the <code>document</code>. */ private void save(XMLWriter out) throws IOException { HashMap<String, String> attributes = new HashMap<String, String>(2); attributes.put(TAG_NAME, name == null ? "" : name); //$NON-NLS-1$ out.startTag(TAG_SECTION, attributes); attributes.clear(); for (Iterator<String> i = items.keySet().iterator(); i.hasNext();) { String key = i.next(); attributes.put(TAG_KEY, key == null ? "" : key); //$NON-NLS-1$ String string = items.get(key); attributes.put(TAG_VALUE, string == null ? "" : string); //$NON-NLS-1$ out.printTag(TAG_ITEM, attributes, true); } attributes.clear(); for (Iterator<String> i = arrayItems.keySet().iterator(); i.hasNext();) { String key = i.next(); attributes.put(TAG_KEY, key == null ? "" : key); //$NON-NLS-1$ out.startTag(TAG_LIST, attributes); String[] value = arrayItems.get(key); attributes.clear(); if (value != null) { for (int index = 0; index < value.length; index++) { String string = value[index]; attributes.put(TAG_VALUE, string == null ? "" : string); //$NON-NLS-1$ out.printTag(TAG_ITEM, attributes, true); } } out.endTag(TAG_LIST); attributes.clear(); } for (Iterator<IDialogSettings> i = sections.values().iterator(); i.hasNext();) { ((DialogSettings) i.next()).save(out); } out.endTag(TAG_SECTION); } /** * A simple XML writer. Using this instead of the javax.xml.transform classes allows * compilation against JCL Foundation (bug 80059). */ private static class XMLWriter extends BufferedWriter { /** current number of tabs to use for indent */ protected int tab; /** the xml header */ protected static final String XML_VERSION = "<?xml version=\"1.0\" encoding=\"UTF-8\"?>"; //$NON-NLS-1$ /** * Create a new XMLWriter * @param output the stream to write the output to * @throws IOException */ public XMLWriter(OutputStream output) throws IOException { this(new OutputStreamWriter(output, "UTF8")); //$NON-NLS-1$ } /** * Create a new XMLWriter * @param output the write to used when writing to * @throws IOException */ public XMLWriter(Writer output) throws IOException { super(output); tab = 0; writeln(XML_VERSION); } private void writeln(String text) throws IOException { write(text); newLine(); } /** * write the intended end tag * @param name the name of the tag to end * @throws IOException */ public void endTag(String name) throws IOException { tab--; printTag("/" + name, null, false); //$NON-NLS-1$ } private void printTabulation() throws IOException { for (int i = 0; i < tab; i++) { super.write('\t'); } } /** * write the tag to the stream and format it by itending it and add new line after the tag * @param name the name of the tag * @param parameters map of parameters * @param close should the tag be ended automatically (=> empty tag) * @throws IOException */ public void printTag(String name, HashMap<String, String> parameters, boolean close) throws IOException { printTag(name, parameters, true, true, close); } private void printTag(String name, HashMap<String, String> parameters, boolean shouldTab, boolean newLine, boolean close) throws IOException { StringBuffer sb = new StringBuffer(); sb.append('<'); sb.append(name); if (parameters != null) { for (Enumeration<String> e = Collections.enumeration(parameters.keySet()); e.hasMoreElements();) { sb.append(" "); //$NON-NLS-1$ String key = e.nextElement(); sb.append(key); sb.append("=\""); //$NON-NLS-1$ sb.append(getEscaped(String.valueOf(parameters.get(key)))); sb.append("\""); //$NON-NLS-1$ } } if (close) { sb.append('/'); } sb.append('>'); if (shouldTab) { printTabulation(); } if (newLine) { writeln(sb.toString()); } else { write(sb.toString()); } } /** * start the tag * @param name the name of the tag * @param parameters map of parameters * @throws IOException */ public void startTag(String name, HashMap<String, String> parameters) throws IOException { startTag(name, parameters, true); tab++; } private void startTag(String name, HashMap<String, String> parameters, boolean newLine) throws IOException { printTag(name, parameters, true, newLine, false); } private static void appendEscapedChar(StringBuffer buffer, char c) { String replacement = getReplacement(c); if (replacement != null) { buffer.append('&'); buffer.append(replacement); buffer.append(';'); } else { buffer.append(c); } } private static String getEscaped(String s) { StringBuffer result = new StringBuffer(s.length() + 10); for (int i = 0; i < s.length(); ++i) { appendEscapedChar(result, s.charAt(i)); } return result.toString(); } private static String getReplacement(char c) { // Encode special XML characters into the equivalent character references. // The first five are defined by default for all XML documents. // The next three (#xD, #xA, #x9) are encoded to avoid them // being converted to spaces on deserialization switch (c) { case '<': return "lt"; //$NON-NLS-1$ case '>': return "gt"; //$NON-NLS-1$ case '"': return "quot"; //$NON-NLS-1$ case '\'': return "apos"; //$NON-NLS-1$ case '&': return "amp"; //$NON-NLS-1$ case '\r': return "#x0D"; //$NON-NLS-1$ case '\n': return "#x0A"; //$NON-NLS-1$ case '\u0009': return "#x09"; //$NON-NLS-1$ } return null; } } }