sessionimpl.java

一个工作流设计及定义的系统,可以直接与数据库结合进行系统工作流程的定义及应用.

/*
 * Copyright (c) 2005, John Mettraux, OpenWFE.org
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without 
 * modification, are permitted provided that the following conditions are met:
 * 
 * . Redistributions of source code must retain the above copyright notice, this
 *   list of conditions and the following disclaimer.  
 * 
 * . Redistributions in binary form must reproduce the above copyright notice, 
 *   this list of conditions and the following disclaimer in the documentation 
 *   and/or other materials provided with the distribution.
 * 
 * . Neither the name of the "OpenWFE" nor the names of its contributors may be
 *   used to endorse or promote products derived from this software without
 *   specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 
 * POSSIBILITY OF SUCH DAMAGE.
 *
 * $Id: SessionImpl.java,v 1.45 2005/05/17 16:41:06 jmettraux Exp $
 */

//
// SessionImpl.java
//
// [e-mail]
//
// generated with 
// jtmpl 1.1.00 16.08.2003 John Mettraux ([e-mail])
//

package openwfe.org.xdbc;

import openwfe.org.Utils;
import openwfe.org.ServiceException;
import openwfe.org.ApplicationContext;
import openwfe.org.xml.XmlUtils;
import openwfe.org.sql.SqlUtils;
import openwfe.org.sql.ds.OwfeDataSource;
import openwfe.org.misc.UniqueIdGenerator;
import openwfe.org.query.item.QueryItem;
import openwfe.org.xdbc.nquery.IdSet;


/**
 * The implementation of Xdbc Session
 *
 * <p><font size=2>CVS Info :
 * <br>$Author: jmettraux $
 * <br>$Id: SessionImpl.java,v 1.45 2005/05/17 16:41:06 jmettraux Exp $ </font>
 *
 * @author [e-mail]
 */
public class SessionImpl

    implements Session

{

    private final static org.apache.log4j.Logger log = org.apache.log4j.Logger
        .getLogger(SessionImpl.class.getName());

    //
    // CONSTANTS & co

    private final static String DOCUMENT = "xdocument";
    private final static String ELEMENT = "xelement";
    private final static String ATTRIBUTE = "xattribute";

    //
    // FIELDS

    private java.sql.Connection connection = null;
    private OwfeDataSource dataSource = null;

    private UniqueIdGenerator uiGenerator = null;

    //
    // CONSTRUCTORS

    public void init (java.sql.Connection con, int idPrefix)
        throws XdbcException
    {
        this.connection = con;
        this.uiGenerator = new UniqueIdGenerator(idPrefix);
    }

    public void init (OwfeDataSource ds, int idPrefix)
        throws XdbcException
    {
        this.dataSource = ds;
        this.uiGenerator = new UniqueIdGenerator(idPrefix);

        log.info("init() with datasource '"+ds.getName()+"'");
    }

    //
    // METHODS from Session

    public void close ()
        throws XdbcException
    {
        releaseConnection();
    }

    public long insert (String clientId, String xmlDocument)
        throws XdbcException
    {
        //log.debug(">>> incoming document \n\n"+xmlDocument+"\n\n<<<");

        try
        {
            return insert
                (clientId, XmlUtils.extractXmlDocument(xmlDocument, false));
        }
        catch (Exception e)
        {
            throw new XdbcException
                ("Failed to parse string to xml", e);
        }
    }

    public long insert
        (final String clientId, 
         final org.jdom.Document doc)
    throws 
        XdbcException
    {
        return insert(-1, clientId, doc);
    }

    public void update 
        (final long xmlDocumentId, 
         final String clientId, 
         final String xmlDocument)
    throws 
        XdbcException
    {
        //
        // here too transaction would be good...

        remove(xmlDocumentId);
        try
        {
            insert
                (xmlDocumentId, 
                 clientId, 
                 XmlUtils.extractXmlDocument(xmlDocument, false));
        }
        catch (Exception e)
        {
            throw new XdbcException
                ("Failed to re-insert document", e);
        }
    }

    public void update 
        (final long xmlDocumentId, 
         final String clientId, 
         final org.jdom.Document doc)
    throws 
        XdbcException
    {
        //
        // here too transaction would be good...

        remove(xmlDocumentId);
        insert(xmlDocumentId, clientId, doc);
    }

    public void remove (final long xmlDocumentId)
        throws XdbcException
    {
        java.sql.Statement st = null;

        try
        {
            st = getConnection().createStatement();

            //
            // BEGIN TRANSACTION would be nice

            //
            // delete from document

            st.executeUpdate
                ("DELETE FROM "+DOCUMENT+" WHERE id="+xmlDocumentId);

            //
            // delete from element

            st.executeUpdate
                ("DELETE FROM "+ELEMENT+" WHERE documentId="+xmlDocumentId);

            //
            // delete from attribute

            st.executeUpdate
                ("DELETE FROM "+ATTRIBUTE+" WHERE documentId="+xmlDocumentId);
        }
        catch (java.sql.SQLException se)
        {
            throw new XdbcException
                ("Failed to remove document from db", se);
        }
        finally
        {
            try
            {
                releaseConnection();
                st.close();
            }
            catch (Exception e)
            {
                // forget it
            }
        }
    }

    public long remove (final String clientId)
        throws XdbcException
    {
        long id = determineDocumentId(clientId);
        remove(id);
        return id;
    }

    public org.jdom.Document find (final long xmlDocumentId)
        throws XdbcException
    {
        java.util.List docIds = new java.util.ArrayList(1);
        docIds.add(new Long(xmlDocumentId));

        java.util.List result = find(docIds);

        if (result == null || result.size() < 1) return null;

        return 
            (org.jdom.Document)result.get(0);
    }

    public String find (final long xmlDocumentId, final String encoding)
        throws XdbcException
    {
        org.jdom.Document doc = find(xmlDocumentId);

        return XmlUtils.toString(doc, encoding);
    }

    public java.util.List find 
        (final java.util.List documentIds, final String encoding)
    throws 
        XdbcException
    {
        java.util.List documents = find(documentIds);

        if (encoding == null) return documents;

        java.util.List result = new java.util.ArrayList(documents.size());

        java.util.Iterator it = documents.iterator();
        while (it.hasNext())
        {
            result.add
                (XmlUtils.toString((org.jdom.Document)it.next(), encoding));
        }

        return result;
    }

    public org.jdom.Document find (final String clientId)
        throws XdbcException
    {
        return find(determineDocumentId(clientId));
    }

    public String find (String clientId, String encoding)
        throws XdbcException
    {
        return find(determineDocumentId(clientId), encoding);
    }

    public IdSet query (final String clientIdLike, final QueryItem query)
        throws XdbcException
    {
        try
        {
            return (IdSet)query
                .query(new Object[] { clientIdLike, getConnection() });
        }
        catch (final Exception e)
        {
            throw new XdbcException
                ("Query failure", e);
        }
        finally
        {
            try
            {
                releaseConnection();
            }
            catch (Exception e)
            {
                // ignore
            }
        }
    }

    public IdSet query (final QueryItem query)
        throws XdbcException
    {
        return query(null, query);
    }

    public java.util.List determineDocumentIds (String clientIdLike)
        throws XdbcException
    {
        return determineDocumentIds(new String[] { clientIdLike });
    }

    /**
     * Returns a list of documentIds based on the LIKE sql strings
     * passed as a parameter.
     */
    public java.util.List determineDocumentIds (String[] clientIdLikes)
        throws XdbcException
    {
        java.sql.Statement st = null;
        java.sql.ResultSet rs = null;
        try
        {
            st = getConnection().createStatement();

            StringBuffer sb = new StringBuffer();

            sb.append("SELECT id FROM ");
            sb.append(DOCUMENT);
            sb.append(" WHERE ");

            for (int i=0; i<clientIdLikes.length; i++)
            {
                sb.append("clientId LIKE '");
                sb.append(clientIdLikes[i]);
                sb.append("' AND ");
            }
            sb.append("isReady = 1");

            String query = sb.toString();

            //log.debug("determineDocumentIds >\n"+query+"\n<");

            rs = st.executeQuery(query);

            java.util.List result = new java.util.ArrayList();

            while(rs.next())
                result.add(new Long(rs.getLong(1)));

            log.debug("found "+result.size()+" documents");

            return result;
        }
        catch (final java.sql.SQLException se)
        {
            final StringBuffer sb = new StringBuffer();

            for (int i=0; i<clientIdLikes.length; i++)
            {
                if (i > 0) sb.append(", ");

                sb.append("'");
                sb.append(clientIdLikes[i]);
                sb.append("'");
            }

            throw new XdbcException
                ("Failed to determine documentIds from clientId LIKE "+
                 sb.toString(), se);
        }
        finally
        {
            try
            {
                releaseConnection();
                rs.close();
                st.close();
            }
            catch (Exception e)
            {
                // forget it
            }
        }
    }

    public int count (String clientIdLike)
        throws XdbcException
    {
        java.sql.Statement st = null;
        java.sql.ResultSet rs = null;
        try
        {
            st = getConnection().createStatement();

            StringBuffer sb = new StringBuffer();

            sb.append("SELECT COUNT(id) FROM ");
            sb.append(DOCUMENT);
            sb.append(" WHERE clientId LIKE '");
            sb.append(clientIdLike);
            sb.append("' AND isReady = 1");

            String query = sb.toString();

            log.debug("count >\n"+query+"\n<");

            rs = st.executeQuery(query);

            int result = 0;

            if (rs.next()) result = rs.getInt(1);

            log.debug("counted "+result+" documents");

            return result;
        }
        catch (java.sql.SQLException se)
        {
            throw new XdbcException
                ("Failed to count documents from clientId LIKE '"+
                 clientIdLike+"'", se);
        }
        finally
        {
            try
            {
                releaseConnection();
                rs.close();
                st.close();
            }
            catch (Exception e)
            {
                // forget it
            }
        }
    }

    public java.util.List listClientIds (String clientIdLike)
        throws XdbcException
    {
        java.sql.Statement st = null;
        java.sql.ResultSet rs = null;
        try
        {
            st = getConnection().createStatement();

            StringBuffer sb = new StringBuffer();

            sb.append("SELECT clientId FROM ");
            sb.append(DOCUMENT);
            sb.append(" WHERE clientId LIKE '");
            sb.append(clientIdLike);
            sb.append("' AND isReady = 1");

            String query = sb.toString();

            log.debug("listClientIds >\n"+query+"\n<");

            rs = st.executeQuery(query);

            java.util.List result = new java.util.ArrayList();

            while (rs.next()) result.add(rs.getString(1));

            return result;
        }
        catch (java.sql.SQLException se)
        {
            throw new XdbcException
                ("Failed to list clientIds LIKE '"+
                 clientIdLike+"'", se);
        }
        finally
        {
            try
            {
                releaseConnection();
                rs.close();
                st.close();
            }
            catch (Exception e)
            {
                // forget it
            }
        }
    }

    public long determineDocumentId (final String clientId)
        throws XdbcException
    {
        java.sql.Statement st = null;
        java.sql.ResultSet rs = null;
        try
        {
            st = getConnection().createStatement();

            StringBuffer sb = new StringBuffer();

            sb.append("SELECT id FROM ");
            sb.append(DOCUMENT);
            sb.append(" WHERE clientId = '");
            sb.append(clientId);
            sb.append("' AND isReady = 1");

            String query = sb.toString();

            rs = st.executeQuery(query);

            if (rs.next()) return rs.getLong(1);
            return -1;
        }
        catch (java.sql.SQLException se)
        {
            throw new XdbcException
                ("Failed to determine documentId from clientId '"+clientId+"'", 
                 se);
        }
        finally
        {
            try
            {
                releaseConnection();
                rs.close();
                st.close();
            }
            catch (Exception e)
            {
                // forget it
            }
        }
    }