/*******************************************************************************
* Copyright (c) 2015 Ericsson 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:
* Marc Dumais (Ericsson) - initial API and implementation (bug 460837)
*******************************************************************************/
package org.eclipse.cdt.dsf.gdb.multicorevisualizer.internal.utils;
import java.io.ByteArrayOutputStream;
import java.io.StringReader;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.transform.OutputKeys;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
import org.w3c.dom.Attr;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.NamedNodeMap;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.xml.sax.InputSource;
import org.xml.sax.helpers.DefaultHandler;
/** encodes and decodes memento to and from different data types; list, map, String*/
public class MementoUtils {
protected static final String ROOT_ELEMENT_TAGNAME = "root_element"; //$NON-NLS-1$
protected static final String ELEMENT_TAGNAME = "elem"; //$NON-NLS-1$
protected static final String ATTRIBUTE_KEY = "key"; //$NON-NLS-1$
protected static final String ATTRIBUTE_VALUE = "value"; //$NON-NLS-1$
/** Returns a XML memento, that encodes a single String parameter */
public static String encodeStringIntoMemento(String str) {
List<String> list = new ArrayList<>();
list.add(str);
return encodeListIntoMemento(list);
}
/** Returns a single String parameter, decoded from a XML memento */
public static String decodeStringFromMemento(String memento) {
return decodeListFromMemento(memento).get(0);
}
/** Returns a XML memento, that encodes a Map of Strings */
public static String encodeMapIntoMemento(Map<String, String> keyPairValues) {
String returnValue = null;
DocumentBuilderFactory dfactory = DocumentBuilderFactory.newInstance();
DocumentBuilder docBuilder = null;
try {
docBuilder = dfactory.newDocumentBuilder();
Document doc = docBuilder.newDocument();
Element rootElement = doc.createElement(ROOT_ELEMENT_TAGNAME);
doc.appendChild(rootElement);
// create one XML element per map entry
for (String key : keyPairValues.keySet()) {
Element elem = doc.createElement(ELEMENT_TAGNAME);
// store key and value as values of 2 attributes
elem.setAttribute(ATTRIBUTE_KEY, key);
elem.setAttribute(ATTRIBUTE_VALUE, keyPairValues.get(key));
rootElement.appendChild(elem);
}
ByteArrayOutputStream s = new ByteArrayOutputStream();
TransformerFactory factory = TransformerFactory.newInstance();
Transformer transformer = factory.newTransformer();
transformer.setOutputProperty(OutputKeys.METHOD, "xml"); //$NON-NLS-1$
transformer.setOutputProperty(OutputKeys.INDENT, "yes"); //$NON-NLS-1$
DOMSource source = new DOMSource(doc);
StreamResult outputTarget = new StreamResult(s);
transformer.transform(source, outputTarget);
returnValue = s.toString("UTF8"); //$NON-NLS-1$
} catch (Exception e) {
e.printStackTrace();
}
return returnValue;
}
/** Returns a Map of Strings, decoded from a XML memento */
public static Map<String, String> decodeMapFromMemento(String memento) {
Map<String, String> keyPairValues = new HashMap<>();
Element root = null;
DocumentBuilder parser;
try {
parser = DocumentBuilderFactory.newInstance().newDocumentBuilder();
parser.setErrorHandler(new DefaultHandler());
root = parser.parse(new InputSource(new StringReader(memento))).getDocumentElement();
NodeList nodeList = root.getChildNodes();
for (int i = 0; i < nodeList.getLength(); i++) {
Node node = nodeList.item(i);
if (node.getNodeType() == Node.ELEMENT_NODE) {
Element elem = (Element) node;
NamedNodeMap nodeMap = elem.getAttributes();
String key = null;
String value = null;
for(int idx = 0; idx < nodeMap.getLength(); idx++) {
Node attrNode = nodeMap.item(idx);
if (attrNode.getNodeType() == Node.ATTRIBUTE_NODE) {
Attr attr = (Attr) attrNode;
if (attr.getName().equals(ATTRIBUTE_KEY)) {
key = attr.getValue();
}
else if (attr.getName().equals(ATTRIBUTE_VALUE)) {
value = attr.getValue();
}
}
}
if (key != null && value != null) {
keyPairValues.put(key, value);
}
else {
throw new Exception();
}
}
}
} catch (Exception e) {
e.printStackTrace();
}
return keyPairValues;
}
/** Returns a XML memento, that encodes a List of Strings */
public static String encodeListIntoMemento(List<String> labels) {
String returnValue = null;
DocumentBuilderFactory dfactory = DocumentBuilderFactory.newInstance();
DocumentBuilder docBuilder = null;
try {
docBuilder = dfactory.newDocumentBuilder();
Document doc = docBuilder.newDocument();
Element rootElement = doc.createElement(ROOT_ELEMENT_TAGNAME);
doc.appendChild(rootElement);
// create one XML element per list entry to save
for (String lbl : labels) {
Element elem = doc.createElement(ELEMENT_TAGNAME);
elem.setAttribute(ATTRIBUTE_VALUE, lbl);
rootElement.appendChild(elem);
}
ByteArrayOutputStream s = new ByteArrayOutputStream();
TransformerFactory factory = TransformerFactory.newInstance();
Transformer transformer = factory.newTransformer();
transformer.setOutputProperty(OutputKeys.METHOD, "xml"); //$NON-NLS-1$
transformer.setOutputProperty(OutputKeys.INDENT, "yes"); //$NON-NLS-1$
DOMSource source = new DOMSource(doc);
StreamResult outputTarget = new StreamResult(s);
transformer.transform(source, outputTarget);
returnValue = s.toString("UTF8"); //$NON-NLS-1$
} catch (Exception e) {
e.printStackTrace();
}
return returnValue;
}
/** Returns a List of Strings, decoded from a XML memento */
public static List<String> decodeListFromMemento(String memento) {
List<String> list = new ArrayList<>();
Element root = null;
DocumentBuilder parser;
try {
parser = DocumentBuilderFactory.newInstance().newDocumentBuilder();
parser.setErrorHandler(new DefaultHandler());
root = parser.parse(new InputSource(new StringReader(memento))).getDocumentElement();
NodeList nodeList = root.getChildNodes();
for (int i = 0; i < nodeList.getLength(); i++) {
Node node = nodeList.item(i);
if (node.getNodeType() == Node.ELEMENT_NODE) {
Element elem = (Element) node;
String value = elem.getAttribute(ATTRIBUTE_VALUE);
if (value != null) {
list.add(value);
}
else {
throw new Exception();
}
}
}
} catch (Exception e) {
e.printStackTrace();
}
return list;
}
}