documentserializableutilities.java

JXTA&#8482 is a set of open, generalized peer-to-peer (P2P) protocols that allow any networked devi

     * @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 = 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 = 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 = 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);
        }
    }

}