/* * Copyright (c) 2002-2003 by OpenSymphony * All rights reserved. */package com.opensymphony.workflow.config;import com.opensymphony.workflow.FactoryException;import com.opensymphony.workflow.StoreException;import com.opensymphony.workflow.loader.*;import com.opensymphony.workflow.loader.ClassLoaderUtil;import com.opensymphony.workflow.spi.WorkflowStore;import com.opensymphony.workflow.util.DefaultVariableResolver;import com.opensymphony.workflow.util.VariableResolver;import org.w3c.dom.*;import java.io.InputStream;import java.io.Serializable;import java.net.URL;import java.util.*;import javax.xml.parsers.*;/** * Default implementation for a configuration object. * This configuration object is passed to the {@link com.opensymphony.workflow.Workflow#setConfiguration(Configuration)} * method. If the configuration is not initialized, the {@link #load(java.net.URL)} method will be called by * the workflow. Alternatively, the caller can explicitly load the configuration by calling that method before * calling {@link com.opensymphony.workflow.Workflow#setConfiguration(Configuration)}. * <p> * The loading behaviour comes into play when specifying a configuration remotely, for example in an EJB * environment. It might be desirable to ensure that the configuration is loaded from within the EJB server, * rather than in the calling client. * * @author Hani Suleiman * @version $Revision: 1.14 $ */public class DefaultConfiguration implements Configuration, Serializable {    //~ Static fields/initializers /////////////////////////////////////////////    private static final long serialVersionUID = 4120889092947132961L;    public static DefaultConfiguration INSTANCE = new DefaultConfiguration();    //~ Instance fields ////////////////////////////////////////////////////////    private Map persistenceArgs = new HashMap();    private String persistenceClass;    private WorkflowFactory factory = new URLWorkflowFactory();    private transient WorkflowStore store = null;    private VariableResolver variableResolver = new DefaultVariableResolver();    private boolean initialized;    //~ Methods ////////////////////////////////////////////////////////////////    public boolean isInitialized() {        return initialized;    }    public boolean isModifiable(String name) {        return factory.isModifiable(name);    }    public void setPersistence(String persistence) {        persistenceClass = persistence;    }    public String getPersistence() {        return persistenceClass;    }    public Map getPersistenceArgs() {        return persistenceArgs;    }    public VariableResolver getVariableResolver() {        return variableResolver;    }    public WorkflowDescriptor getWorkflow(String name) throws FactoryException {        WorkflowDescriptor workflow = factory.getWorkflow(name);        if (workflow == null) {            throw new FactoryException("Unknown workflow name");        }        return workflow;    }    public String[] getWorkflowNames() throws FactoryException {        return factory.getWorkflowNames();    }    public WorkflowStore getWorkflowStore() throws StoreException {        if (store == null) {            String clazz = getPersistence();            try {                store = (WorkflowStore) Class.forName(clazz).newInstance();            } catch (Exception ex) {                throw new StoreException("Error creating store", ex);            }            store.init(getPersistenceArgs());        }        return store;    }    public void load(URL url) throws FactoryException {        InputStream is = getInputStream(url);        if (is == null) {            throw new FactoryException("Cannot find osworkflow.xml configuration file in classpath or in META-INF");        }        try {            DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();            dbf.setNamespaceAware(true);            DocumentBuilder db;            try {                db = dbf.newDocumentBuilder();            } catch (ParserConfigurationException e) {                throw new FactoryException("Error creating document builder", e);            }            Document doc = db.parse(is);            Element root = (Element) doc.getElementsByTagName("osworkflow").item(0);            Element p = XMLUtil.getChildElement(root, "persistence");            Element resolver = XMLUtil.getChildElement(root, "resolver");            Element factoryElement = XMLUtil.getChildElement(root, "factory");            if (resolver != null) {                String resolverClass = resolver.getAttribute("class");                if (resolverClass != null) {                    variableResolver = (VariableResolver) ClassLoaderUtil.loadClass(resolverClass, getClass()).newInstance();                }            }            persistenceClass = p.getAttribute("class");            List args = XMLUtil.getChildElements(p, "property");            //persistenceArgs = new HashMap();            for (int i = 0; i < args.size(); i++) {                Element e = (Element) args.get(i);                persistenceArgs.put(e.getAttribute("key"), e.getAttribute("value"));            }            if (factoryElement != null) {                String clazz = null;                try {                    clazz = factoryElement.getAttribute("class");                    if (clazz == null) {                        throw new FactoryException("factory does not specify a class attribute");                    }                    factory = (WorkflowFactory) ClassLoaderUtil.loadClass(clazz, getClass()).newInstance();                    Properties properties = new Properties();                    List props = XMLUtil.getChildElements(factoryElement, "property");                    for (int i = 0; i < props.size(); i++) {                        Element e = (Element) props.get(i);                        properties.setProperty(e.getAttribute("key"), e.getAttribute("value"));                    }                    factory.init(properties);                    factory.initDone();                } catch (FactoryException ex) {                    throw ex;                } catch (Exception ex) {                    throw new FactoryException("Error creating workflow factory " + clazz, ex);                }            }            initialized = true;        } catch (FactoryException e) {            throw e;        } catch (Exception e) {            throw new FactoryException("Error in workflow config", e);        }    }    public boolean removeWorkflow(String workflow) throws FactoryException {        return factory.removeWorkflow(workflow);    }    public boolean saveWorkflow(String name, WorkflowDescriptor descriptor, boolean replace) throws FactoryException {        return factory.saveWorkflow(name, descriptor, replace);    }    /**     * Load the default configuration from the current context classloader.     * The search order is:     * <li>Specified URL</li>     * <li>osworkflow.xml</li>     * <li>/osworkflow.xml</li>     * <li>META-INF/osworkflow.xml</li>     * <li>/META-INF/osworkflow.xml</li>     */    protected InputStream getInputStream(URL url) {        InputStream is = null;        if (url != null) {            try {                is = url.openStream();            } catch (Exception ex) {            }        }        ClassLoader classLoader = Thread.currentThread().getContextClassLoader();        if (is == null) {            try {                is = classLoader.getResourceAsStream("osworkflow.xml");            } catch (Exception e) {            }        }        if (is == null) {            try {                is = classLoader.getResourceAsStream("/osworkflow.xml");            } catch (Exception e) {            }        }        if (is == null) {            try {                is = classLoader.getResourceAsStream("META-INF/osworkflow.xml");            } catch (Exception e) {            }        }        if (is == null) {            try {                is = classLoader.getResourceAsStream("/META-INF/osworkflow.xml");            } catch (Exception e) {            }        }        return is;    }    /**     * Get the workflow factory for this configuration.     * This method should never ever be called from client code!     */    WorkflowFactory getFactory() {        return factory;    }}