owfequeryitem.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: OwfeQueryItem.java,v 1.2 2005/05/17 16:41:06 jmettraux Exp $
 */

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

package openwfe.org.xdbc.nquery;

import openwfe.org.query.QueryException;
import openwfe.org.query.QueryConfiguration;
import openwfe.org.query.sets.Set;
import openwfe.org.query.item.Query;
import openwfe.org.sql.SqlUtils;


/**
 * A query item focussed on how OpenWFE workitem fields (attributes) are 
 * structered (in XML) and thus capable of querying like : "please return
 * me workitems with a field named "X" that has a value of "Y"...
 *
 * <p><font size=2>CVS Info :
 * <br>$Author: jmettraux $
 * <br>$Id: OwfeQueryItem.java,v 1.2 2005/05/17 16:41:06 jmettraux Exp $ </font>
 *
 * @author [e-mail]
 */
public class OwfeQueryItem

    extends AtomicQueryItem

{

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

    //
    // CONSTANTS & co

    //public final static String STRING_TYPE = "string";

    public final static String ID = "id";
    public final static String PARENT_ID = "parentElementId";

    public final static String KEY = "key";
    public final static String VALUE = "value";


    //public final static String XML_ELT_NAME = "owfe-query";
    //public final static String XML_ATT_KEY = "key";
    //public final static String XML_ATT_VALUE = "value";
    //public final static String XML_ATT_KEY_TYPE = "key-type";
    //public final static String XML_ATT_VALUE_TYPE = "value-type";

    //
    // FIELDS

    private String key = null;
    private String keyType = null;
    private String value = null;
    private String valueType = null;

    //
    // CONSTRUCTORS

    public void init 
        (final QueryConfiguration config, final Query parent, final Object arg)
    throws
        QueryException
    {
        final org.jdom.Element elt = (org.jdom.Element)arg;

        this.key = elt.getAttributeValue("key");
        this.keyType = elt.getAttributeValue("key-type");
        this.value = elt.getAttributeValue("value");
        this.valueType = elt.getAttributeValue("value-type");

        setValueOperator(elt.getAttributeValue("op"));
    }

    /*
    public OwfeQueryItem 
        (String key, String value)
    {
        this.key = key;
        this.value = value;
    }

    public OwfeQueryItem
        (String key, String value, int valueOperator)
    {
        this.key = key;
        this.value = value;
        this.valueOperator = valueOperator;
    }

    public OwfeQueryItem 
        (String key, String valueType, String value)
    {
        this.key = key;
        this.valueType = valueType;
        this.value = value;
    }

    public OwfeQueryItem 
        (String keyType, String key, String valueType, String value)
    {
        this.keyType = keyType;
        this.key = key;
        this.valueType = valueType;
        this.value = value;
    }
    */

    //
    // METHODS from QueryItem

    public String getQueryString ()
    {
        //
        // is never used
        
        return null;
    }

    /*
    public org.jdom.Element encode ()
    {
        org.jdom.Element result = new org.jdom.Element(XML_ELT_NAME);

        result.setAttribute(XML_ATT_KEY, this.key);
        result.setAttribute(XML_ATT_VALUE, this.value);

        if (this.keyType != null)
            result.setAttribute(XML_ATT_KEY_TYPE, this.keyType);
        if (this.valueType != null)
            result.setAttribute(XML_ATT_VALUE_TYPE, this.valueType);

        result.setAttribute(XML_ATT_VALUE_OPERATOR, encodeValueOperator());

        return result;
    }
    */

    //public boolean matches (org.jdom.Element elt)
    public boolean validate (final Object o)
        throws QueryException
    {
        final org.jdom.Element elt = (org.jdom.Element)o;

        if (elt.getName().equals("entry"))
        {
            org.jdom.Element eKey = getFirstChild(elt.getChild("key"));
            org.jdom.Element eValue = getFirstChild(elt.getChild("value"));

            /*
            log.debug("\n   targetKey    '"+this.keyType+"' --> '"+this.key+"'");
            log.debug("\n   targetValue  '"+this.valueType+"' --> '"+this.value+"'");
            log.debug("\n   eKey '"+eKey.getName()+"' --> '"+eKey.getTextTrim()+"'");
            log.debug("\n   eValue '"+eValue.getName()+"' --> '"+eValue.getTextTrim()+"'");
            */

            boolean result = eKey.getTextTrim().matches(this.key);

            if (this.keyType != null)
                result = result && (eKey.getName().equals(this.keyType));
            if (this.valueType != null)
                result = result && (eValue.getName().equals(this.valueType));

            if (getValueOperator() == LIKE)
                result = result && eValue.getTextTrim().matches(this.value);
            else
                result = result && compare(eValue.getTextTrim(), this.value);

            if (result) return true;
        }

        return childrenMatches(elt);
    }

    private org.jdom.Element getFirstChild (org.jdom.Element elt)
    {
        if (elt.getChildren().size() > 0) 
            return (org.jdom.Element)elt.getChildren().get(0);
        return null;
    }

    //public Set query (String clientIdLike, java.sql.Connection con)
    public Set query (final Object queryArg)
        throws QueryException
    {
        final Object[] os = (Object[])queryArg;

        final String clientIdLike = (String)os[0];
        final java.sql.Connection con = (java.sql.Connection)os[1];

        final IdSet result = new IdSet();

        //
        // querying for value first,
        // it might make the query quicker as there are
        // less chances to hit a good value,
        // key names are more homogeneous

        log.debug("querying for value");

        java.util.Set valueResult = buildResultSet
            (clientIdLike, con, VALUE, this.valueType, this.value);

        if (valueResult == null) return result;
            // nothing found

        log.debug("querying for key");

        java.util.Set keyResult = buildResultSet
            (clientIdLike, con, KEY, this.keyType, this.key);

        if (keyResult == null) return result;
            // nothing found

        java.util.Iterator it = keyResult.iterator();
        while (it.hasNext())
        {
            String sid = (String)it.next();
            if (valueResult.contains(sid))
            {
                String[] ss = splitSid(sid);

                //log.debug("docid    : "+ss[0]);
                //log.debug("clientid : "+ss[2]);

                result.add(Long.parseLong(ss[0]), ss[2]);
                    // adding the docId
            }
        }

        return result;
    }

    private String[] splitSid (String sid)
    {
        String[] result = new String[3];

        int i = sid.indexOf("|");
        result[0] = sid.substring(0, i);
        sid = sid.substring(i+1);

        i = sid.indexOf("|");
        result[1] = sid.substring(0, i);
        sid = sid.substring(i+1);

        result[2] = sid;

        /*
        log.debug
            ("\nsid[0] : "+result[0]+
             "\nsid[1] : "+result[1]+
             "\nsid[2] : "+result[2]);
        */

        return result;
    }

    //
    // METHODS

    protected java.util.Set buildResultSet 
        (String clientIdLike,
         java.sql.Connection con, 
         String keyOrValue,
         String type, 
         String value)
    throws
        QueryException
    {
        //
        // FIRST STAGE
        
        StringBuffer sb = new StringBuffer();

        sb.append("SELECT DISTINCT ");
        sb.append(DOCUMENT_ID); 
        sb.append(", "); 
        sb.append(CLIENT_ID);
        sb.append(", "); 
        sb.append(PARENT_ID);
        sb.append(" FROM ");
        sb.append(ELEMENTS); sb.append(", "); sb.append(DOCUMENTS);

        sb.append(" WHERE ");

        sb.append(ELEMENTS); sb.append("."); sb.append(DOCUMENT_ID);
        sb.append(" = ");
        sb.append(DOCUMENTS); sb.append("."); sb.append("id");

        if (type != null)
        {
            sb.append(" AND ");
            sb.append(ELTNAME); 
            sb.append(" = '"); 
            sb.append(type);
            sb.append("'");
        }

        sb.append(" AND ");
        sb.append(ELTVALUE); 
        if (keyOrValue.equals("key"))
            sb.append(" LIKE ");
        else
            sb.append(getValueOperator());
        sb.append(SqlUtils.prepareString(value));

        if (clientIdLike != null)
        {
            sb.append(" AND ");
            sb.append(CLIENT_ID);
            sb.append(" LIKE ");
            sb.append(SqlUtils.prepareString(clientIdLike));
        }

        //sb.append(";");

        String query = sb.toString();

        log.debug(" ~~~ 1st stage query >\n"+query+"\n<");

        //
        // execute 1st stage query

        java.util.Map results = new java.util.HashMap();
        
        java.sql.Statement st = null;
        java.sql.ResultSet rs = null;
        try
        {
            st = con.createStatement();
            rs = st.executeQuery(query);

            while (rs.next())
            {
                Long docId = new Long(rs.getLong(1));
                String clientId = rs.getString(2);
                Long parentId = new Long(rs.getLong(3));

                Object[] os = new Object[3];

                os[0] = docId;
                os[1] = clientId;

                //log.debug(" ~~~~ putting "+docId+" --> "+parentId);

                results.put(parentId, os);
            }
        }
        catch (final java.sql.SQLException se)
        {
            throw new QueryException
                ("1st stage of query failed", se);
        }
        finally
        {
            try
            {
                rs.close();
                st.close();
            }
            catch (Exception e)
            {
                // ignore
            }
        }

        //
        // SECOND STAGE
        
        if (results.size() < 1) return null;

        sb = new StringBuffer();

        sb.append("SELECT ");
        sb.append(ID); sb.append(", "); sb.append(PARENT_ID);
        sb.append(" FROM ");
        sb.append(ELEMENTS);

        sb.append(" WHERE ");

        sb.append(ELTNAME);
        sb.append(" = '"); sb.append(keyOrValue); sb.append("' AND ");

        sb.append("( ");
        java.util.Iterator it = results.keySet().iterator();
        while (it.hasNext())
        {
            sb.append(ID);
            sb.append(" = ");
            sb.append(it.next());

            if (it.hasNext()) sb.append(" OR ");
        }
        sb.append(" )");

        //sb.append(";");

        query = sb.toString();

        log.debug(" ~~~ 2nd stage query >\n"+query+"\n<");

        // 
        // execute 2nd stage query

        try
        {
            st = con.createStatement();
            rs = st.executeQuery(query);

            while (rs.next())
            {
                Long id = new Long(rs.getLong(1));
                Long parentId = new Long(rs.getLong(2));

                Object[] os = (Object[])results.get(id);
                os[2] = parentId;
            }
        }
        catch (final java.sql.SQLException se)
        {
            throw new QueryException
                ("2nd stage of query failed", se);
        }
        finally
        {
            try
            {
                rs.close();
                st.close();
            }
            catch (Exception e)
            {
                // ignore
            }
        }

        //
        // build result set
        
        java.util.Set result = new java.util.HashSet(results.size());

        it = results.values().iterator();
        while (it.hasNext())
        {
            Object[] os = (Object[])it.next();

            if (os[2] == null) continue;

            result.add
                (os[0].toString() + "|" + 
                 os[2].toString() + "|" +
                 os[1].toString());
        }

        return result;
    }

    //
    // STATIC METHODS

    /*
    public static QueryItem decode (org.jdom.Element elt)
    {
        String key = elt.getAttributeValue(XML_ATT_KEY);
        String value = elt.getAttributeValue(XML_ATT_VALUE);
        String keyType = elt.getAttributeValue(XML_ATT_KEY_TYPE);
        String valueType = elt.getAttributeValue(XML_ATT_VALUE_TYPE);
        String valueOperator = elt.getAttributeValue(XML_ATT_VALUE_OPERATOR);

        OwfeQueryItem oqi = new OwfeQueryItem(keyType, key, valueType, value);
        oqi.setValueOperator(decodeValueOperator(valueOperator));
        return oqi;
    }
    */

}