springhibernateworkflowfactory.java

一个很好实用的工作流OSWORKFLOW开发例子.有着非常优秀的灵活性.

/*
 * Copyright (c) 2002-2003 by OpenSymphony
 * All rights reserved.
 */
/*
 * Created on 30-nov-2005
 *
 * To change the template for this generated file go to
 * Window - Preferences - Java - Code Generation - Code and Comments
 */
package com.opensymphony.workflow.spi.hibernate;

import com.opensymphony.workflow.FactoryException;
import com.opensymphony.workflow.InvalidWorkflowDescriptorException;
import com.opensymphony.workflow.loader.AbstractWorkflowFactory;
import com.opensymphony.workflow.loader.WorkflowDescriptor;

import net.sf.hibernate.HibernateException;
import net.sf.hibernate.Session;
import net.sf.hibernate.SessionFactory;

import org.springframework.orm.hibernate.HibernateCallback;
import org.springframework.orm.hibernate.HibernateTemplate;

import java.sql.SQLException;

import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;


/**
 * DOCUMENT ME!
 *
 * @author $author$
 * @version $Revision: 1.1 $
 */
public class SpringHibernateWorkflowFactory extends AbstractWorkflowFactory {
    //~ Static fields/initializers /////////////////////////////////////////////

    private static boolean forceReload;

    //~ Instance fields ////////////////////////////////////////////////////////

    private Map workflows;
    private SessionFactory sessionFactory;
    private boolean reload = false;
    private boolean validate = false;

    //~ Constructors ///////////////////////////////////////////////////////////

    public SpringHibernateWorkflowFactory() {
        super();
    }

    //~ Methods ////////////////////////////////////////////////////////////////

    public void setLayout(String workflowName, Object layout) {
    }

    public Object getLayout(String workflowName) {
        return null;
    }

    public boolean isModifiable(String name) {
        return true;
    }

    public String getName() {
        return "";
    }

    public void setReload(boolean reload) {
        this.reload = reload;
    }

    public void setSessionFactory(SessionFactory sessionFactory) {
        this.sessionFactory = sessionFactory;
    }

    public void setValidate(boolean validate) {
        this.validate = validate;
    }

    public WorkflowDescriptor getWorkflow(String name, boolean validate) throws FactoryException {
        if (!workflows.containsKey(name)) {
            throw new FactoryException("Unknown workflow name \"" + name + '\"');
        }

        if (reload || forceReload) {
            forceReload = false;
            loadWorkflow(name, validate);
        }

        return (WorkflowDescriptor) workflows.get(name);
    }

    public String[] getWorkflowNames() throws FactoryException {
        int i = 0;
        String[] res = new String[workflows.keySet().size()];
        Iterator it = workflows.keySet().iterator();

        while (it.hasNext()) {
            res[i++] = (String) it.next();
        }

        return res;
    }

    public void createWorkflow(String name) {
    }

    public static void forceReload() {
        forceReload = true;
    }

    public void initDone() throws FactoryException {
        try {
            workflows = new HashMap();

            List workflowNames = new HibernateTemplate(sessionFactory).find("select wfn.workflowName from WorkflowName wfn");

            for (Iterator iter = workflowNames.iterator(); iter.hasNext();) {
                String wfn = iter.next().toString();
                loadWorkflow(wfn, validate);
            }
        } catch (Exception e) {
            throw new FactoryException(e);
        }
    }

    public boolean removeWorkflow(String name) throws FactoryException {
        final HibernateTemplate hibernateTemplate = new HibernateTemplate(sessionFactory);
        WorkflowName wfn = (WorkflowName) hibernateTemplate.load(WorkflowName.class, name);

        if (wfn != null) {
            hibernateTemplate.delete(wfn);

            return true;
        }

        return false;
    }

    public void renameWorkflow(String oldName, String newName) {
        final HibernateTemplate hibernateTemplate = new HibernateTemplate(sessionFactory);
        WorkflowName wfn = (WorkflowName) hibernateTemplate.load(WorkflowName.class, oldName);
        wfn.setWorkflowName(newName);
    }

    public void save() {
    }

    public boolean saveWorkflow(String name, WorkflowDescriptor descriptor, boolean replace) throws FactoryException {
        WorkflowName wfn = new WorkflowName();
        wfn.setWorkflowName(name);
        wfn.setWorkflowDescriptor(descriptor);

        final HibernateTemplate hibernateTemplate = new HibernateTemplate(sessionFactory);
        hibernateTemplate.saveOrUpdate(wfn);

        initDone();

        return false;
    }

    private synchronized void loadWorkflow(final String workflowName, final boolean validate) throws FactoryException {
        try {
            new HibernateTemplate(sessionFactory).execute(new HibernateCallback() {
                    public Object doInHibernate(Session session) throws HibernateException, SQLException {
                        try {
                            WorkflowName wfn = (WorkflowName) session.load(WorkflowName.class, workflowName);

                            if (validate) {
                                wfn.getWorkflowDescriptor().validate();
                            }

                            workflows.put(wfn.getWorkflowName(), wfn.getWorkflowDescriptor());

                            return null;
                        } catch (InvalidWorkflowDescriptorException e) {
                            throw new RuntimeException(e);
                        }
                    }
                });
        } catch (Exception e) {
            throw new FactoryException(e);
        }
    }
}