slcodec.java

java实现的P2P多agent中间件

		}
		buffer.append(')');
	}


	private void encodeAndAppend(AbsPrimitive val) throws CodecException {
		Object v = val.getObject();
		if (v instanceof Date)
			buffer.append(ISO8601.toString((Date)v));
		else if (v instanceof Number) {
			buffer.append(v.toString());
			if (preserveJavaTypes) {
				if (v instanceof Long) {
					buffer.append('L');
				}
				else if (v instanceof Float) {
					buffer.append('F');
				}
			}
		}
		else if (v instanceof byte[]) {
			// Note: Currently uses Java default charset, may need to use another one 
			byte[] b = (byte[]) v;
			buffer.append('#');
			buffer.append(b.length);
			buffer.append('"');
			// FIXME: Should we use base64 encoding?
			buffer.append(new String(b));
		}
		else if (v instanceof Boolean) 
			buffer.append(v.toString());
		else {
			String vs = v.toString();
			if ( (CaseInsensitiveString.equalsIgnoreCase("true",vs)) ||
					(CaseInsensitiveString.equalsIgnoreCase("false",vs)) ) {
				// quote true and false to avoid confusion with booleans
				buffer.append('"');
				buffer.append(vs);
				buffer.append('"');
			} else
				encodeAndAppend(vs);
		}
	}

	private void encodeAndAppend(AbsObject val) throws CodecException { 
		if (val instanceof AbsPrimitive)      encodeAndAppend( (AbsPrimitive)val);
		else if (val instanceof AbsPredicate) encodeAndAppend( (AbsPredicate)val);
		else if (val instanceof AbsIRE)       encodeAndAppend( (AbsIRE)val);
		else if (val instanceof AbsVariable)  encodeAndAppend( (AbsVariable)val);
		//	if (val instanceof AbsAgentAction) return toString( (AbsAgentAction)val);
		else if (val instanceof AbsAggregate) encodeAndAppend( (AbsAggregate)val);
		else if (val instanceof AbsConcept)   encodeAndAppend( (AbsConcept)val);
		else throw new CodecException("SLCodec cannot encode this object "+val);
	}


	/**
	 * Decodes the content to an abstract description.
	 * @param content the content as a String.
	 * @return the content as an abstract description.
	 * @throws CodecException
	 */
	public AbsContentElement decode(String content) throws CodecException {
		return decode(null, content); 
	}

	/**
	 * Decodes the content to an abstract description.
	 * @param ontology the ontology.
	 * @param content the content as a String.
	 * @return the content as an abstract description.
	 * @throws CodecException
	 */
	public synchronized AbsContentElement decode(Ontology ontology, String content) throws CodecException {
		try {
			AbsContentElementList tuple = null;
			if (preserveJavaTypes) {
				extendedParser.reinit(ontology, content);
				tuple = extendedParser.Content();
			}
			else {
				parser.reinit(ontology, content);
				tuple = parser.Content();
			}
			if (tuple.size() > 1)
				return tuple;
			else  // if there is a single ContentExpression than return just it, not the tuple
				return tuple.get(0);
		}  catch(Throwable e) { // both ParseException and TokenMgrError
			throw new CodecException("Parse exception", e);
		}
	}



	/**
	 * Decodes the content to an abstract description, where the content is known to be a Term.
	 * @param ontology the ontology.
	 * @param cterm the term as a String.
	 * @return the content as an abstract description.
	 * @throws CodecException
	 * @since JADE 3.4
	 */
	public synchronized AbsTerm decodeTerm(Ontology ontology, String term) throws CodecException {
		try {
			if (preserveJavaTypes) {
				extendedParser.reinit(ontology, term);
				return extendedParser.Term();
			}
			else {
				parser.reinit(ontology, term);
				return parser.Term();
			}
		}  catch(Throwable e) { // both ParseException and TokenMgrError
			throw new CodecException("Parse exception", e);
		}
	}


	/**
	 * Encodes the content into a String, where the content is known to be a Term.
	 * @param ontology the ontology.
	 * @param term the termt as an abstract descriptor
	 * @return the content as a String 
	 * @throws CodecException
	 * @since JADE 3.4
	 */
	public synchronized String encodeTerm(Ontology ontology, AbsTerm term) throws CodecException {
		try {
			domainOnto = ontology;
			buffer = new StringBuffer();
			encodeAndAppend(term);
			return buffer.toString();
		} finally {
			buffer = null; //frees the memory
		}
	}


	/**
	 * Decodes the content to an abstract description, where the content is known to be a Well-formed Formula
	 * @param ontology the ontology.
	 * @param formula the content as a String.
	 * @return the content as an abstract description.
	 * @throws CodecException
	 * @since JADE 3.4
	 */
	public synchronized AbsPredicate decodeFormula(Ontology ontology, String formula) throws CodecException {
		try {
			if (preserveJavaTypes) {
				extendedParser.reinit(ontology, formula);
				return extendedParser.Wff();
			}
			else {
				parser.reinit(ontology, formula);
				return parser.Wff();
			}
		}  catch(Throwable e) { // both ParseException and TokenMgrError
			throw new CodecException("Parse exception", e);
		}
	}


	/**
	 * Encodes the content into a String, where the content is known to be a Well-formed Formula
	 * @param ontology the ontology.
	 * @param formula the formula as an abstract descriptor
	 * @return the content as a String 
	 * @throws CodecException
	 * @since JADE 3.4
	 */
	public synchronized String encodeFormula(Ontology ontology, AbsPredicate formula) throws CodecException {
		try {
			domainOnto = ontology;
			buffer = new StringBuffer();
			encodeAndAppend(formula);
			return buffer.toString();
		} finally {
			buffer = null; //frees the memory
		}
	}


	public static void main(String[] args) {
		SLCodec codec = null;
		char contentType = 'C';
		try {
			codec = new SLCodec(Integer.parseInt(args[0]));
			contentType = (args.length > 1 ? args[1].charAt(0) : 'C');
		} catch (Exception e) {
			System.out.println("usage: SLCodec SLLevel [ContentType]\n where SLLevel can be 0 for SL0, 1 for SL1, 2 for SL2, 3 or more for full SL \n and where ContentType is a char representing the type of content to be parsed: C for a contentexpression (default), T for a term, F for a formula");
			System.exit(0);
		}

		while (true) {
			try {
				System.out.println("insert an SL " + (contentType == 'F' ? "Well-Formed Formula" : (contentType == 'T' ? "Term" : "Content Expression")) + " to parse (all the expression on a single line!): ");
				BufferedReader buff = new BufferedReader(new InputStreamReader(System.in));
				String str = buff.readLine();
				System.out.println("\n\n");
				if (contentType == 'F') {
					AbsPredicate result = codec.decodeFormula(null, str);
					System.out.println("DUMP OF THE DECODE OUTPUT (just for debugging):");
					System.out.println(result);
					System.out.println("\n\n");
					System.out.println("AFTER ENCODE:");
					System.out.println(codec.encodeFormula(null, result));
					System.out.println("\n\n");
				} else if (contentType == 'T') {
					AbsTerm result = codec.decodeTerm(null, str);
					System.out.println("DUMP OF THE DECODE OUTPUT (just for debugging):");
					System.out.println(result);
					System.out.println("\n\n");
					System.out.println("AFTER ENCODE:");
					System.out.println(codec.encodeTerm(null, result));
					System.out.println("\n\n");
				} else {
					AbsContentElement result = codec.decode(str);
					System.out.println("DUMP OF THE DECODE OUTPUT (just for debugging):");
					System.out.println(result);
					System.out.println("\n\n");
					System.out.println("AFTER ENCODE:");
					System.out.println(codec.encode(result));
					System.out.println("\n\n");
				}
			} catch(Exception pe) {
				pe.printStackTrace();
				//System.exit(0);
			}
		}
	}

	/**
	 * @return the ontology containing the schemas of the operator
	 * defined in this language
	 */
	public Ontology getInnerOntology() {
		return slOnto;
	}

	private String[] getSlotNames(AbsObject abs) throws CodecException {
		String[] slotNames = null;
		String type = abs.getTypeName();
		if (domainOnto != null) {
			// If an ontology is specified, get the slot names from it 
			// (and not directly from the abstract descriptor val) to preserve 
			// the order
			try {
				ObjectSchema s = domainOnto.getSchema(type);
				if (s == null) {
					throw new CodecException("No schema found for symbol "+type);
				}
				slotNames = s.getNames();
			}
			catch (OntologyException oe) {
				throw new CodecException("Error getting schema for symbol "+type, oe);
			}
		}
		else {
			slotNames = abs.getNames();
		}
		return slotNames;
	}

	private boolean getEncodingByOrder(AbsObject abs) throws CodecException {
		if (domainOnto != null) {
			String type = abs.getTypeName();
			try {
				ObjectSchema s = domainOnto.getSchema(type);
				return s.getEncodingByOrder();
			}
			catch (Exception e) {
				// Just ignore it
			}
		}
		return false;
	}

	/**
	 * Encode the slots of an abstract descriptor by order, i.e. 
	 * without writing the slot names. Also take into account that, in
	 * order to ensure a correct parsing, empty slots can only occur at 
	 * the end.
	 * Append this encoded string to buffer.
	 */
	private void encodeSlotsByOrder(AbsObject val, String[] slotNames) throws CodecException {
		boolean lastSlotEmpty = false;
		for (int i=0; i<slotNames.length; i++) {
			AbsTerm t = (AbsTerm)val.getAbsObject(slotNames[i]);
			if (t != null) {
				if (lastSlotEmpty) {
					throw new CodecException("Non-empty slot "+slotNames[i]+" follows empty slot "+slotNames[i-1]);
				}
				buffer.append(' ');
				encodeAndAppend(t);
			}
			else {
				lastSlotEmpty = true;
			}
		}
	}

	/**
	 * Encode the slots of an abstract descriptor by name, i.e. 
	 * writing for each non-empty slot the slot name followed by the
	 * slot value.
	 * Append this encoded string to buffer.
	 */
	private void encodeSlotsByName(AbsObject val, String[] slotNames) throws CodecException {
		for (int i=0; i<slotNames.length; i++) {
			AbsTerm t = (AbsTerm)val.getAbsObject(slotNames[i]);
			if (t != null) {
				// if this isn't un unnamed slot, then encode it otherwise just encode its value
				if (!slotNames[i].startsWith(this.UNNAMEDPREFIX)) {
					buffer.append(" :");
					encodeAndAppend(slotNames[i]);
				}
				buffer.append(' ');
				encodeAndAppend(t);
			}
		}
	}

	/**
	 * Restore parser after deserialization. <br>
	 * The readResolve method is called when ObjectInputStream has read an object from the stream 
	 * and is preparing to return it to the caller. <br>
	 * The readResolve method is not invoked on the object until the object is fully constructed. 
	 */
	protected Object readResolve() throws java.io.ObjectStreamException {
		initParser();
		return this; 
	}

//#MIDP_EXCLUDE_END
}