documentserializableutilities.java

jxta_src_2.41b jxta 2.41b 最新版源码 from www.jxta.org

	/**
	 *  Get the value of a Child Element 
	 *
	 * @param element The Parant Element
	 * @param tagName The Tag Name of the Child Element that will contain the value
	 * @param defaultValue The return value if there is no Child Element with that Tag Name
	 * @return the value converted from a String
	 **/
	public static long getLong(Element element, String tagName, long defaultValue) {
		Element childElement = getChildElement(element, tagName);
		
		if (childElement != null)
			return getLong(childElement);
		else
			return defaultValue;
	}	
		
	/**
	 *  Add an Element with the specified tagname and value (converted to a String)
	 *
	 * @param element Parent Element that the new element will be added to
	 * @param tagName TagName to be used for the created Child Element
	 * @param value The value that will be stored in the Element as a String
	 **/
	public static void addDouble(Element element, String tagName, double value) {
		StructuredDocument structuredDocument = (StructuredDocument) element.getRoot();
		Element childElement = structuredDocument.createElement(tagName, Double.toString(value));
		element.appendChild(childElement);
	}

	/**
	 *  Get  the value of an element converted from a String
	 *
	 * @param element Element that contains the value
	 * @return the value converted from a String
	 **/
	public static double getDouble(Element element) {
		return Double.parseDouble((String) element.getValue());
	}

	/**
	 *  Get the value of a Child Element 
	 *
	 * @param element The Parant Element
	 * @param tagName The Tag Name of the Child Element that will contain the value
	 * @param defaultValue The return value if there is no Child Element with that Tag Name
	 * @return the value converted from a String
	 **/
	public static double getDouble(Element element, String tagName, double defaultValue) {
		Element childElement = getChildElement(element, tagName);
		
		if (childElement != null)
			return getDouble(childElement);
		else
			return defaultValue;
	}	
		
	/**
	 *  Add an Element with the specified tagname and value (converted to a String)
	 *
	 * @param element Parent Element that the new element will be added to
	 * @param tagName TagName to be used for the created Child Element
	 * @param value The value that will be stored in the Element as a String
	 **/
	public static void addBoolean(Element element, String tagName, boolean value) {
		StructuredDocument structuredDocument = (StructuredDocument) element.getRoot();
		Element childElement = structuredDocument.createElement(tagName, value ? "true" : "false");
		element.appendChild(childElement);
	}

	/**
	 *  Get  the value of an element converted from a String ("true" or "false")
	 *
	 * @param element Element that contains the value
	 * @return the value converted from a String
	 **/
	public static boolean getBoolean(Element element) {
		return "true".equals((String) element.getValue());
	}

	/**
	 *  Get the value of a Child Element 
	 *
	 * @param element The Parant Element
	 * @param tagName The Tag Name of the Child Element that will contain the value
	 * @param defaultValue The return value if there is no Child Element with that Tag Name
	 * @return the value converted from a String
	 **/
	public static boolean getBoolean(Element element, String tagName, boolean defaultValue) {
		Element childElement = getChildElement(element, tagName);
		
		if (childElement != null)
			return getBoolean(childElement);
		else
			return defaultValue;
	}	

	/**
	 *  Add an Element with the specified tagname and value
	 *
	 * @param element Parent Element that the new element will be added to
	 * @param tagName TagName to be used for the created Child Element
	 * @param value The value that will be stored in the Element
	 **/
	public static void addString(Element element, String tagName, String value) {
		StructuredDocument structuredDocument = (StructuredDocument) element.getRoot();
		Element childElement = structuredDocument.createElement(tagName, value);
		element.appendChild(childElement);
	}

	/**
	 *  Get  the value of an element as a String
	 *
	 * @param element Element that contains the value
	 * @return the value converted from a String
	 **/
	public static String getString(Element element) {
		return (String) element.getValue();
	}

	/**
	 *  Get the value of a Child Element 
	 *
	 * @param element The Parant Element
	 * @param tagName The Tag Name of the Child Element that will contain the value
	 * @param defaultValue The return value if there is no Child Element with that Tag Name
	 * @return The value found in the Element
	 **/
	public static String getString(Element element, String tagName, String defaultValue) {
		Element childElement = getChildElement(element, tagName);
		
		if (childElement != null)
			return getString(childElement);
		else
			return defaultValue;
	}

	/**
	 *  Convert a DocumentSerializable object to its XML representation as a String
	 *  
	 *  The Root TagName will be 'documentSerializable' by default
	 *  
	 * @param documentSerializable The Object to be converted to an XML Document
	 * @return The String representation of an XML Document
 	 * @throws DocumentSerializationException if Unable to serialize object.
	 **/
	public static String toXmlString(DocumentSerializable documentSerializable) throws DocumentSerializationException {
		return toXmlString(documentSerializable, "documentSerializable");
	}

	/**
	 *  Convert a DocumentSerializable object to its XML representation as a String
	 *  
	 *  The Root TagName will be 'documentSerializable' by default
	 *  
	 * @param documentSerializable The Object to be converted to an XML Document
	 * @param rootTagName The Root tagName for the XML Document
	 * @return The String representation of an XML Document
 	 * @throws DocumentSerializationException if Unable to serialize object.
	 **/
	public static String toXmlString(DocumentSerializable documentSerializable, String rootTagName) throws DocumentSerializationException {
		try {
			StringWriter bout = new StringWriter();
			XMLDocument document = DocumentSerializableUtilities.createStructuredXmlDocument(rootTagName, documentSerializable);
			document.sendToWriter(bout);
			bout.close();
                        
			return bout.toString();
		} catch (IOException e) {
			throw new DocumentSerializationException("Error converting to String", e);
		}
	}
	
	/**
	 *  Write a DocumentSerializable object as an XML Document to a Stream
	 *  
	 *  The Root TagName will be 'documentSerializable' by default
	 *  
	 * @param out The Stream to write the document to
	 * @param documentSerializable The Object to be converted to an XML Document
 	 * @throws DocumentSerializationException if Unable to serialize object.
 	 * @throws IOException if I/O error while writing
	 **/
	public static void writeAsXmlString(OutputStream out, DocumentSerializable documentSerializable) throws IOException, DocumentSerializationException {
		writeAsXmlString(out, documentSerializable, "documentSerializable");
	}
	
	/**
	 *  Write a DocumentSerializable object as an XML Document to a Stream
	 *  
	 *  The Root TagName will be 'documentSerializable' by default
	 *  
	 * @param out The Stream to write the document to
	 * @param rootTagName The Root tagName for the XML Document
	 * @param documentSerializable The Object to be converted to an XML Document
 	 * @throws DocumentSerializationException if Unable to serialize object.
 	 * @throws IOException if I/O error while writing
	 **/
	public static void writeAsXmlString(OutputStream out, DocumentSerializable documentSerializable, String rootTagName) throws IOException, DocumentSerializationException {
			StructuredDocument document = DocumentSerializableUtilities.createStructuredXmlDocument(rootTagName, documentSerializable);
			document.sendToStream(out);
	}

	/**
	 *  Write a DocumentSerializable object as an XML Document to StdErr
	 *  
	 *  The Root TagName will be 'documentSerializable' by default
	 *  
	 * @param documentSerializable The DocumentSerializable to be printed.
	 **/
	public static void printAsXmlString(DocumentSerializable documentSerializable) {
		try {
			if (documentSerializable == null)
				System.err.println("<null DocumentSerializable>");
			else
				writeAsXmlString(System.err, documentSerializable);
		} catch (Exception e) {
			System.err.println("<Error converting DocumentSerializable to XML doc: " + e);
		}
	}
	

	/**
	 *  Create a DocumentSerializable Object from an XML Document
	 *  
	 * @param buf The XML document contained in a String
	 * @param clazz The Class of the resurrected object (must implement DocumentSerializable and have a public no-arg constructor)
	 * @return An object of type 'clazz'
 	 * @throws DocumentSerializationException if Unable to parse object.
	 **/
	public static DocumentSerializable getDocumentSerializableFromXml(String buf, Class clazz) throws DocumentSerializationException {
		try {
			XMLDocument xmlDoc = (XMLDocument) StructuredDocumentFactory.newStructuredDocument(MimeMediaType.XMLUTF8, new StringReader( buf));
			return getDocumentSerializable(xmlDoc.getRoot(), clazz);			
		} catch (IOException readErr) {
			throw new DocumentSerializationException("Unable to read the document", readErr);
		} catch (JxtaException e) {
			throw new DocumentSerializationException("Unable to get the document", e);
		}
	}

	/**
	 *  Create a DocumentSerializable Object from an XML Document
	 *  
	 * @param buf The XML document contained in a byte buffer
	 * @param clazz The Class of the resurrected object (must implement DocumentSerializable and have a public no-arg constructor)
	 * @return An object of type 'clazz'
 	 * @throws DocumentSerializationException if Unable to parse object.
	 **/
	public static DocumentSerializable getDocumentSerializableFromXml(byte buf[], Class clazz) throws DocumentSerializationException {
		return getDocumentSerializableFromXml( new ByteArrayInputStream(buf), clazz);
	}

	/**
	 *  Create a DocumentSerializable Object from an XML Document
	 *  
	 * @param in The Stream containing an XML Document to be read
	 * @param clazz The Class of the resurrected object (must implement DocumentSerializable and have a public no-arg constructor)
	 * @return An object of type 'clazz'
 	 * @throws DocumentSerializationException if Unable to parse object.
	 **/
	public static DocumentSerializable getDocumentSerializableFromXml(InputStream in, Class clazz) throws DocumentSerializationException {
		try {
			XMLDocument xmlDoc = (XMLDocument) StructuredDocumentFactory.newStructuredDocument(MimeMediaType.XMLUTF8, in);
			return getDocumentSerializable(xmlDoc.getRoot(), clazz);			
		} catch (IOException readErr) {
			throw new DocumentSerializationException("Unable to read the document", readErr);
		} catch (JxtaException e) {
			throw new DocumentSerializationException("Unable to get the document", e);
		}
	}

}