ipojo/plugin/src/main/java/org/apache/felix/ipojo/parser/ManifestMetadataParser.java

/* 
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
package org.apache.felix.ipojo.parser;

import java.util.Dictionary;
import java.util.logging.Level;

import org.apache.felix.ipojo.metadata.Attribute;
import org.apache.felix.ipojo.metadata.Element;
import org.apache.felix.ipojo.plugin.IPojoPluginConfiguration;

/**
 * Manifest Metadata parser.
 * Read a manifest file and construct metadata
 * @author <a href="mailto:felix-dev@incubator.apache.org">Felix Project Team</a>
 */
public class ManifestMetadataParser {

	/**
	 * Manifest Headers.
	 */
	private Dictionary m_headers;

	/**
	 * Element list.
	 */
	private Element[] m_elements = new Element[0];

    /**
     * @return the component metadata.
     * @throws ParseException when a parsing error occurs
     */
    public Element[] getComponentsMetadata() throws ParseException {
    	return m_elements[0].getElements("Component");
    }

    private void addElement(Element elem) {
    	for (int i = 0; (m_elements != null) && (i < m_elements.length); i++) {
            if (m_elements[i] == elem) { return; }
        }

        if (m_elements != null) {
            Element[] newElementsList = new Element[m_elements.length + 1];
            System.arraycopy(m_elements, 0, newElementsList, 0, m_elements.length);
            newElementsList[m_elements.length] = elem;
            m_elements = newElementsList;
        }
        else { m_elements = new Element[] {elem}; }
	}

    private Element removeLastElement() {
		int idx = -1;
		idx = m_elements.length - 1;
		Element last = m_elements[idx];
        if (idx >= 0) {
            if ((m_elements.length - 1) == 0) {
            	// It is the last element of the list;
            	m_elements = new Element[0];
            	}
            else {
            	// Remove the last element of the list :
                Element[] newElementsList = new Element[m_elements.length - 1];
                System.arraycopy(m_elements, 0, newElementsList, 0, idx);
                m_elements = newElementsList;
            }
        }
        return last;
	}

	/**
	 * Parse the given dictionnary and create the components manager.
	 * @param dict : the given headers of the manifest file
	 * @throws ParseException : if any error occurs
	 */
	public void parse(Dictionary dict) throws ParseException {
		m_headers = dict;
		String componentClassesStr = (String)m_headers.get("iPOJO-Components");
		parseElements(componentClassesStr.trim());

	}
	
	/**
	 * PArse the metadata from the string given in argument.
	 * @param metadata : the metadata
	 * @throws ParseException when a parse error occurs
	 */
	public void parse(String metadata) throws ParseException {
		parseElements(metadata);
	}

	private void parseElements(String s) {
		//Add the ipojo element inside the element list
		addElement(new Element("iPOJO", ""));
		char[] string = s.toCharArray();

		for (int i = 0; i < string.length; i++) {
			char c = string[i];
			switch(c) {

			case '$' :
				String attName = "";
				String attValue = "";
				String attNs = ""; 
				i++;
				c = string[i];
				while (c != '=') {
					if(c == ':') {
						attNs = attName;
						attName= "";
					} else { attName = attName + c; } 
					i = i + 1;
					c = string[i];
				}
				i++; // skip =
				c = string[i];
				while (c != ' ') {
					attValue = attValue + c;
					i++;
					c = string[i];
				}
				Attribute att = new Attribute(attName, attNs ,attValue);
				IPojoPluginConfiguration.getLogger().log(Level.INFO, "Detect a new  attribute : '" + "[" + attNs + "]" + attName + "' = '" + attValue + "'");
				m_elements[m_elements.length - 1].addAttribute(att);
				break;

			case '}' :
				Element lastElement = removeLastElement();
				IPojoPluginConfiguration.getLogger().log(Level.INFO, "End of the element : " + lastElement.getName());
				if (m_elements.length != 0) {
					Element newQueue = m_elements[m_elements.length - 1];
					newQueue.addElement(lastElement);
				}
				else {
					addElement(lastElement);
				}
				break;
			case ' ' : break; // do nothing;
			default :
					String name = "";
					String ns = "";
					c = string[i];
					while (c != ' ') {
						if(c == ':') {
							ns = name;
							name = "";
							i++;
						} 
						else {
							name = name + c;
							i++;
							c = string[i];
						}
					}
					// Skip spaces
					while (string[i] == ' ') { i = i + 1; }
					i = i + 1; // skip {
				    Element elem = new Element(name, ns);
					addElement(elem);
					IPojoPluginConfiguration.getLogger().log(Level.INFO, "Start an new element : " + name);
				break;
			}
			}
		}

}