bundles/org.eclipse.urischeme/src/org/eclipse/urischeme/internal/registration/PlistFileWriter.java - platform/eclipse.platform.ui - Git at Google

 /*******************************************************************************
  * Copyright (c) 2018 SAP SE and others.
  *
  * This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License 2.0
  * which accompanies this distribution, and is available at
  * https://www.eclipse.org/legal/epl-2.0/
  *
  * SPDX-License-Identifier: EPL-2.0
  *
  * Contributors:
  *     SAP SE - initial version
  *******************************************************************************/
 package org.eclipse.urischeme.internal.registration;

 import java.io.BufferedWriter;
 import java.io.Closeable;
 import java.io.IOException;
 import java.io.Reader;
 import java.io.Writer;

 import javax.xml.parsers.DocumentBuilder;
 import javax.xml.parsers.DocumentBuilderFactory;
 import javax.xml.parsers.ParserConfigurationException;
 import javax.xml.transform.TransformerException;
 import javax.xml.transform.TransformerFactory;
 import javax.xml.transform.dom.DOMSource;
 import javax.xml.transform.stream.StreamResult;
 import javax.xml.xpath.XPathConstants;
 import javax.xml.xpath.XPathExpression;
 import javax.xml.xpath.XPathExpressionException;
 import javax.xml.xpath.XPathFactory;

 import org.w3c.dom.Document;
 import org.w3c.dom.Element;
 import org.w3c.dom.Node;
 import org.w3c.dom.NodeList;
 import org.w3c.dom.Text;
 import org.xml.sax.InputSource;
 import org.xml.sax.SAXException;

 /**
  * Used to change the CFBundleURLTypes property of a Mac .plist file. Adds
  * handler entries for uri schemes in "CFBundleURLSchemes" elements. Can also
  * remove schemes.
  */
 public class PlistFileWriter {

 	private static final String XPATH_PLIST_DICT_CF_BUNDLE_URL_TYPES_KEY = "/plist/dict/key[text()=\"CFBundleURLTypes\"]"; //$NON-NLS-1$
 	private static final String XPATH_PLIST_DICT_CF_BUNDLE_URL_TYPES_ARRAY = XPATH_PLIST_DICT_CF_BUNDLE_URL_TYPES_KEY
 			+ "/following-sibling::array"; //$NON-NLS-1$
 	private static final String ELEMENT_NAME_KEY = "key"; //$NON-NLS-1$
 	private static final String ELEMENT_NAME_ARRAY = "array"; //$NON-NLS-1$
 	private static final String ELEMENT_NAME_STRING = "string"; //$NON-NLS-1$
 	private static final String ELEMENT_NAME_DICT = "dict"; //$NON-NLS-1$
 	private static final String KEY_VALUE_CF_BUNDLE_URL_TYPES = "CFBundleURLTypes"; //$NON-NLS-1$
 	private static final String KEY_VALUE_CF_BUNDLE_URL_NAME = "CFBundleURLName"; //$NON-NLS-1$
 	private static final String KEY_VALUE_CF_BUNDLE_URL_SCHEMES = "CFBundleURLSchemes"; //$NON-NLS-1$
 	private Document document;
 	private Element array;

 	/**
 	 * Creates an instance of the PlistFileWriter. Throws an
 	 * {@link IllegalStateException} if the given {@link Reader} does not provide
 	 * .plist file.
 	 *
 	 * @param reader The file reader of the .plist file
 	 *
 	 * @throws IllegalArgumentException if file cannot be understood as .plist file
 	 */
 	public PlistFileWriter(Reader reader) {
 		this.document = getDom(reader);
 		this.array = getOrCreateBundleUrlTypesAndArray();
 	}

 	/**
 	 * Checks if the given scheme is registered in this .plist file
 	 *
 	 * @param scheme that should be checked for registration
 	 * @return <code>true</code> if scheme registered; <code>false</code> otherwise
 	 */
 	public boolean isRegisteredScheme(String scheme) {
 		Util.assertUriSchemeIsLegal(scheme);

 		return getExistingElementFor(scheme) != null;
 	}

 	/**
 	 * Adds an entry for the given scheme in the CFBundleURLSchemes element of the
 	 * .plist file. Creates the CFBundleURLTypes element if not yet existing.
 	 * Otherwise adds CFBundleURLSchemes element.
 	 *
 	 * @param scheme            The uri scheme which should be handled by the
 	 *                          application of the .plist file
 	 * @param schemeDescription The human readable description of the scheme
 	 *
 	 * @throws IllegalArgumentException if the given scheme contains illegal
 	 *                                  characters
 	 *
 	 * @see #removeScheme(String)
 	 *
 	 * @see <a href= "https://tools.ietf.org/html/rfc3986#section-3.1">Uniform
 	 *      Resource Identifier (URI): Generic Syntax</a>
 	 *
 	 */
 	public void addScheme(String scheme, String schemeDescription) {
 		// check precondition
 		Util.assertUriSchemeIsLegal(scheme);

 		if (getExistingElementFor(scheme) != null) {
 			return;
 		}

 		// add dict element
 		addIndent(array, 3);
 		Element dictInArray = addChildNode(array, ELEMENT_NAME_DICT, null);

 		// add key CFBundleURLName
 		addIndent(dictInArray, 4);
 		addChildNode(dictInArray, ELEMENT_NAME_KEY, KEY_VALUE_CF_BUNDLE_URL_NAME);

 		// add string
 		addIndent(dictInArray, 5);
 		addChildNode(dictInArray, ELEMENT_NAME_STRING, schemeDescription);

 		// add key CFBundleURLSchemes
 		addIndent(dictInArray, 4);
 		addChildNode(dictInArray, ELEMENT_NAME_KEY, KEY_VALUE_CF_BUNDLE_URL_SCHEMES);

 		// add array
 		addIndent(dictInArray, 5);
 		Element schemeArray = addChildNode(dictInArray, ELEMENT_NAME_ARRAY, null);

 		// add string
 		addIndent(schemeArray, 6);
 		addChildNode(schemeArray, ELEMENT_NAME_STRING, scheme);

 		// indent closing tags
 		addIndent(schemeArray, 5);
 		addIndent(dictInArray, 3);
 	}

 	/**
 	 * Removes the corresponding CFBundleURLSchemes element for the given scheme
 	 * from the CFBundleURLTypes element of the .plist file. Removes the
 	 * CFBundleURLTypes element completely if it is empty (no handled schemes) after
 	 * removal.
 	 *
 	 * @param scheme The uri scheme which should not be handled anymore by the
 	 *               application of the .plist file.
 	 *
 	 * @throws IllegalArgumentException if the given scheme contains illegal
 	 *                                  characters
 	 *
 	 * @see #addScheme(String, String)
 	 *
 	 * @see <a href=
 	 *      "https://tools.ietf.org/html/rfc3986#section-3.1">https://tools.ietf.org/html/rfc3986#section-3.1</a>
 	 *
 	 */
 	public void removeScheme(String scheme) {
 		Util.assertUriSchemeIsLegal(scheme);

 		Element dict = getExistingElementFor(scheme);
 		if (dict == null) {
 			// not found, no need to remove
 			return;
 		}

 		Node arrayNode = dict.getParentNode();
 		removeTextNode(arrayNode, dict.getPreviousSibling()); // remove tab and line break before dict
 		arrayNode.removeChild(dict);
 	}

 	/**
 	 * Writes the content (xml) of the .plist file to the given {@link Writer}
 	 *
 	 * @param writer The Writer to which the xml should be written to, e.g.
 	 *               {@link BufferedWriter}
 	 *
 	 */
 	public void writeTo(Writer writer) {
 		boolean hasDict = false;
 		for (int i = 0; i < array.getChildNodes().getLength(); i++) {
 			Node child = array.getChildNodes().item(i);
 			if ("dict".equals(child.getNodeName())) { //$NON-NLS-1$
 				hasDict = true;
 				break;
 			}
 		}
 		// check if no schemes in cfbundlurltypes
 		if (!hasDict) {
 			Node keyNode = evaluateXpathOnElement(document, XPATH_PLIST_DICT_CF_BUNDLE_URL_TYPES_KEY);
 			if (keyNode != null) {
 				keyNode.getParentNode().removeChild(keyNode);
 				array.getParentNode().removeChild(array);
 			}
 		} else {
 			// indent last closing tag
 			addIndent(array, 2);
 		}

 		transformDocument(writer);
 	}

 	private void transformDocument(Writer writer) {
 		try {
 			DOMSource source = new DOMSource(this.document);
 			TransformerFactory.newInstance().newTransformer().transform(source, new StreamResult(writer));
 		} catch (TransformerException e) {
 			throw new IllegalStateException(e);
 		} finally {
 			close(writer);
 		}
 	}

 	private Document getDom(Reader reader) {
 		DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
 		try {
 			DocumentBuilder builder = factory.newDocumentBuilder();
 			return builder.parse(new InputSource(reader));
 		} catch (ParserConfigurationException | IOException | SAXException e) {
 			throw new IllegalArgumentException(e);
 		} finally {
 			close(reader);
 		}
 	}

 	private void close(Closeable closeable) {
 		try {
 			closeable.close();
 		} catch (IOException e) {
 			throw new IllegalStateException(e);
 		}
 	}

 	private Element getOrCreateBundleUrlTypesAndArray() {
 		Element arrayNode = evaluateXpathOnElement(this.document, XPATH_PLIST_DICT_CF_BUNDLE_URL_TYPES_ARRAY);
 		if (arrayNode != null) {
 			// adapt whitespace of array
 			if (removeTextNode(arrayNode, arrayNode.getLastChild())) {
 				addLineBreak(arrayNode);
 			}
 		} else {
 			// create CFBundleURLTypes and it's array
 			Element plistElement = document.getDocumentElement();
 			NodeList dictElements = plistElement.getElementsByTagName(ELEMENT_NAME_DICT);
 			if (dictElements.getLength() == 0) {
 				throw new IllegalStateException("Top level 'DICT' element could not be found"); //$NON-NLS-1$
 			}
 			Node dictElement = dictElements.item(0);
 			addIndent(dictElement, 1);
 			addChildNode(dictElement, ELEMENT_NAME_KEY, KEY_VALUE_CF_BUNDLE_URL_TYPES);

 			addIndent(dictElement, 2);
 			arrayNode = addChildNode(dictElement, ELEMENT_NAME_ARRAY, null);
 		}
 		return arrayNode;
 	}

 	private boolean removeTextNode(Node parent, Node textNode) {
 		if (textNode instanceof Text) {
 			parent.removeChild(textNode);
 			return true;
 		}
 		return false;
 	}

 	private Element addChildNode(Node parent, String name, String value) {
 		Element newElement = document.createElement(name);
 		if (value != null) {
 			newElement.appendChild(document.createTextNode(value));
 		} else {
 			addLineBreak(newElement);
 		}
 		parent.appendChild(newElement);
 		addLineBreak(parent);
 		return newElement;
 	}

 	private void addLineBreak(Node node) {
 		node.appendChild(document.createTextNode("\n")); //$NON-NLS-1$
 	}

 	private void addIndent(Node node, int indent) {
 		StringBuilder builder = new StringBuilder();
 		for (int i = 0; i < indent; i++) {
 			builder.append("	"); //$NON-NLS-1$
 		}
 		node.appendChild(document.createTextNode(builder.toString()));
 	}

 	private Element getExistingElementFor(String scheme) {
 		String xpathToSchemeDictElement = XPATH_PLIST_DICT_CF_BUNDLE_URL_TYPES_ARRAY
 				+ "/dict/key[text()=\"CFBundleURLSchemes\"]/following-sibling::array/string[text()=\"" + scheme //$NON-NLS-1$
 				+ "\"]/../.."; //$NON-NLS-1$

 		return evaluateXpathOnElement(this.document, xpathToSchemeDictElement);
 	}

 	private Element evaluateXpathOnElement(Node node, String xpath) {
 		try {
 			XPathExpression xpathExpression = XPathFactory.newInstance().newXPath().compile(xpath);
 			NodeList nodeList = (NodeList) xpathExpression.evaluate(node, XPathConstants.NODESET);
 			return nodeList.getLength() == 0 ? null : (Element) nodeList.item(0);
 		} catch (XPathExpressionException e) {
 			throw new IllegalStateException(e); // cannot happen
 		}
 	}
 }
	/*******************************************************************************
	* Copyright (c) 2018 SAP SE and others.
	*
	* This program and the accompanying materials
	* are made available under the terms of the Eclipse Public License 2.0
	* which accompanies this distribution, and is available at
	* https://www.eclipse.org/legal/epl-2.0/
	*
	* SPDX-License-Identifier: EPL-2.0
	*
	* Contributors:
	* SAP SE - initial version
	*******************************************************************************/
	package org.eclipse.urischeme.internal.registration;

	import java.io.BufferedWriter;
	import java.io.Closeable;
	import java.io.IOException;
	import java.io.Reader;
	import java.io.Writer;

	import javax.xml.parsers.DocumentBuilder;
	import javax.xml.parsers.DocumentBuilderFactory;
	import javax.xml.parsers.ParserConfigurationException;
	import javax.xml.transform.TransformerException;
	import javax.xml.transform.TransformerFactory;
	import javax.xml.transform.dom.DOMSource;
	import javax.xml.transform.stream.StreamResult;
	import javax.xml.xpath.XPathConstants;
	import javax.xml.xpath.XPathExpression;
	import javax.xml.xpath.XPathExpressionException;
	import javax.xml.xpath.XPathFactory;

	import org.w3c.dom.Document;
	import org.w3c.dom.Element;
	import org.w3c.dom.Node;
	import org.w3c.dom.NodeList;
	import org.w3c.dom.Text;
	import org.xml.sax.InputSource;
	import org.xml.sax.SAXException;

	/**
	* Used to change the CFBundleURLTypes property of a Mac .plist file. Adds
	* handler entries for uri schemes in "CFBundleURLSchemes" elements. Can also
	* remove schemes.
	*/
	public class PlistFileWriter {

	private static final String XPATH_PLIST_DICT_CF_BUNDLE_URL_TYPES_KEY = "/plist/dict/key[text()=\"CFBundleURLTypes\"]"; //$NON-NLS-1$
	private static final String XPATH_PLIST_DICT_CF_BUNDLE_URL_TYPES_ARRAY = XPATH_PLIST_DICT_CF_BUNDLE_URL_TYPES_KEY
	+ "/following-sibling::array"; //$NON-NLS-1$
	private static final String ELEMENT_NAME_KEY = "key"; //$NON-NLS-1$
	private static final String ELEMENT_NAME_ARRAY = "array"; //$NON-NLS-1$
	private static final String ELEMENT_NAME_STRING = "string"; //$NON-NLS-1$
	private static final String ELEMENT_NAME_DICT = "dict"; //$NON-NLS-1$
	private static final String KEY_VALUE_CF_BUNDLE_URL_TYPES = "CFBundleURLTypes"; //$NON-NLS-1$
	private static final String KEY_VALUE_CF_BUNDLE_URL_NAME = "CFBundleURLName"; //$NON-NLS-1$
	private static final String KEY_VALUE_CF_BUNDLE_URL_SCHEMES = "CFBundleURLSchemes"; //$NON-NLS-1$
	private Document document;
	private Element array;

	/**
	* Creates an instance of the PlistFileWriter. Throws an
	* {@link IllegalStateException} if the given {@link Reader} does not provide
	* .plist file.
	*
	* @param reader The file reader of the .plist file
	*
	* @throws IllegalArgumentException if file cannot be understood as .plist file
	*/
	public PlistFileWriter(Reader reader) {
	this.document = getDom(reader);
	this.array = getOrCreateBundleUrlTypesAndArray();
	}

	/**
	* Checks if the given scheme is registered in this .plist file
	*
	* @param scheme that should be checked for registration
	* @return <code>true</code> if scheme registered; <code>false</code> otherwise
	*/
	public boolean isRegisteredScheme(String scheme) {
	Util.assertUriSchemeIsLegal(scheme);

	return getExistingElementFor(scheme) != null;
	}

	/**
	* Adds an entry for the given scheme in the CFBundleURLSchemes element of the
	* .plist file. Creates the CFBundleURLTypes element if not yet existing.
	* Otherwise adds CFBundleURLSchemes element.
	*
	* @param scheme The uri scheme which should be handled by the
	* application of the .plist file
	* @param schemeDescription The human readable description of the scheme
	*
	* @throws IllegalArgumentException if the given scheme contains illegal
	* characters
	*
	* @see #removeScheme(String)
	*
	* @see <a href= "https://tools.ietf.org/html/rfc3986#section-3.1">Uniform
	* Resource Identifier (URI): Generic Syntax</a>
	*
	*/
	public void addScheme(String scheme, String schemeDescription) {
	// check precondition
	Util.assertUriSchemeIsLegal(scheme);

	if (getExistingElementFor(scheme) != null) {
	return;
	}

	// add dict element
	addIndent(array, 3);
	Element dictInArray = addChildNode(array, ELEMENT_NAME_DICT, null);

	// add key CFBundleURLName
	addIndent(dictInArray, 4);
	addChildNode(dictInArray, ELEMENT_NAME_KEY, KEY_VALUE_CF_BUNDLE_URL_NAME);

	// add string
	addIndent(dictInArray, 5);
	addChildNode(dictInArray, ELEMENT_NAME_STRING, schemeDescription);

	// add key CFBundleURLSchemes
	addIndent(dictInArray, 4);
	addChildNode(dictInArray, ELEMENT_NAME_KEY, KEY_VALUE_CF_BUNDLE_URL_SCHEMES);

	// add array
	addIndent(dictInArray, 5);
	Element schemeArray = addChildNode(dictInArray, ELEMENT_NAME_ARRAY, null);

	// add string
	addIndent(schemeArray, 6);
	addChildNode(schemeArray, ELEMENT_NAME_STRING, scheme);

	// indent closing tags
	addIndent(schemeArray, 5);
	addIndent(dictInArray, 3);
	}

	/**
	* Removes the corresponding CFBundleURLSchemes element for the given scheme
	* from the CFBundleURLTypes element of the .plist file. Removes the
	* CFBundleURLTypes element completely if it is empty (no handled schemes) after
	* removal.
	*
	* @param scheme The uri scheme which should not be handled anymore by the
	* application of the .plist file.
	*
	* @throws IllegalArgumentException if the given scheme contains illegal
	* characters
	*
	* @see #addScheme(String, String)
	*
	* @see <a href=
	* "https://tools.ietf.org/html/rfc3986#section-3.1">https://tools.ietf.org/html/rfc3986#section-3.1</a>
	*
	*/
	public void removeScheme(String scheme) {
	Util.assertUriSchemeIsLegal(scheme);

	Element dict = getExistingElementFor(scheme);
	if (dict == null) {
	// not found, no need to remove
	return;
	}

	Node arrayNode = dict.getParentNode();
	removeTextNode(arrayNode, dict.getPreviousSibling()); // remove tab and line break before dict
	arrayNode.removeChild(dict);
	}

	/**
	* Writes the content (xml) of the .plist file to the given {@link Writer}
	*
	* @param writer The Writer to which the xml should be written to, e.g.
	* {@link BufferedWriter}
	*
	*/
	public void writeTo(Writer writer) {
	boolean hasDict = false;
	for (int i = 0; i < array.getChildNodes().getLength(); i++) {
	Node child = array.getChildNodes().item(i);
	if ("dict".equals(child.getNodeName())) { //$NON-NLS-1$
	hasDict = true;
	break;
	}
	}
	// check if no schemes in cfbundlurltypes
	if (!hasDict) {
	Node keyNode = evaluateXpathOnElement(document, XPATH_PLIST_DICT_CF_BUNDLE_URL_TYPES_KEY);
	if (keyNode != null) {
	keyNode.getParentNode().removeChild(keyNode);
	array.getParentNode().removeChild(array);
	}
	} else {
	// indent last closing tag
	addIndent(array, 2);
	}

	transformDocument(writer);
	}

	private void transformDocument(Writer writer) {
	try {
	DOMSource source = new DOMSource(this.document);
	TransformerFactory.newInstance().newTransformer().transform(source, new StreamResult(writer));
	} catch (TransformerException e) {
	throw new IllegalStateException(e);
	} finally {
	close(writer);
	}
	}

	private Document getDom(Reader reader) {
	DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
	try {
	DocumentBuilder builder = factory.newDocumentBuilder();
	return builder.parse(new InputSource(reader));
	} catch (ParserConfigurationException \| IOException \| SAXException e) {
	throw new IllegalArgumentException(e);
	} finally {
	close(reader);
	}
	}

	private void close(Closeable closeable) {
	try {
	closeable.close();
	} catch (IOException e) {
	throw new IllegalStateException(e);
	}
	}

	private Element getOrCreateBundleUrlTypesAndArray() {
	Element arrayNode = evaluateXpathOnElement(this.document, XPATH_PLIST_DICT_CF_BUNDLE_URL_TYPES_ARRAY);
	if (arrayNode != null) {
	// adapt whitespace of array
	if (removeTextNode(arrayNode, arrayNode.getLastChild())) {
	addLineBreak(arrayNode);
	}
	} else {
	// create CFBundleURLTypes and it's array
	Element plistElement = document.getDocumentElement();
	NodeList dictElements = plistElement.getElementsByTagName(ELEMENT_NAME_DICT);
	if (dictElements.getLength() == 0) {
	throw new IllegalStateException("Top level 'DICT' element could not be found"); //$NON-NLS-1$
	}
	Node dictElement = dictElements.item(0);
	addIndent(dictElement, 1);
	addChildNode(dictElement, ELEMENT_NAME_KEY, KEY_VALUE_CF_BUNDLE_URL_TYPES);

	addIndent(dictElement, 2);
	arrayNode = addChildNode(dictElement, ELEMENT_NAME_ARRAY, null);
	}
	return arrayNode;
	}

	private boolean removeTextNode(Node parent, Node textNode) {
	if (textNode instanceof Text) {
	parent.removeChild(textNode);
	return true;
	}
	return false;
	}

	private Element addChildNode(Node parent, String name, String value) {
	Element newElement = document.createElement(name);
	if (value != null) {
	newElement.appendChild(document.createTextNode(value));
	} else {
	addLineBreak(newElement);
	}
	parent.appendChild(newElement);
	addLineBreak(parent);
	return newElement;
	}

	private void addLineBreak(Node node) {
	node.appendChild(document.createTextNode("\n")); //$NON-NLS-1$
	}

	private void addIndent(Node node, int indent) {
	StringBuilder builder = new StringBuilder();
	for (int i = 0; i < indent; i++) {
	builder.append(" "); //$NON-NLS-1$
	}
	node.appendChild(document.createTextNode(builder.toString()));
	}

	private Element getExistingElementFor(String scheme) {
	String xpathToSchemeDictElement = XPATH_PLIST_DICT_CF_BUNDLE_URL_TYPES_ARRAY
	+ "/dict/key[text()=\"CFBundleURLSchemes\"]/following-sibling::array/string[text()=\"" + scheme //$NON-NLS-1$
	+ "\"]/../.."; //$NON-NLS-1$

	return evaluateXpathOnElement(this.document, xpathToSchemeDictElement);
	}

	private Element evaluateXpathOnElement(Node node, String xpath) {
	try {
	XPathExpression xpathExpression = XPathFactory.newInstance().newXPath().compile(xpath);
	NodeList nodeList = (NodeList) xpathExpression.evaluate(node, XPathConstants.NODESET);
	return nodeList.getLength() == 0 ? null : (Element) nodeList.item(0);
	} catch (XPathExpressionException e) {
	throw new IllegalStateException(e); // cannot happen
	}
	}
	}