newsms.java

这是一个J2EE的一个小内容

/**
 * This class serves as a model component, in a MVC pattern.
 * The action class or the web service manager class calls the
 * relevant method in this class.
 * This class is responsible for processing any business processes and
 * gets the result from a datasource.
 * It returns the result set in a pre-defined data object
 *
 */

/**
 * Change History:
 * Author	        Date	       Version   Details
 * Jerome Josephraj   28 October 2002   1.0      Created
 *
 */


package com.ddj.wsstruts.ms;

//Java imports
import java.sql.ResultSet;
import java.util.Collection;
import java.util.Vector;
import com.ddj.wsstruts.valueobject.News;
import com.ddj.wsstruts.constant.SystemConstants;
import com.ddj.wsstruts.ms.AbstractMs;
import com.ddj.wsstruts.util.DatabaseManager;
import com.ddj.wsstruts.valueobject.NewsSearchResult;

//log4j imports
import org.apache.log4j.Category;

public class NewsMs extends AbstractMs {
    
    /*
     * This method is used to search for a news
     * The required news details are passed through News bean from
     * the news maintenance action class. This method checks for all the
     * mandatory fields and raises validationerrors for any missing mandatory field
     *
     * Mandatory fields are - none
     *
     *  @NewsSearchResult Object
     *  @return Collection object
     */
    public Collection getNews(NewsSearchResult newsSearchCOD)
    throws Exception {
        
        //Check if the newsCOD exists
        if(newsSearchCOD == null) {
            throw new Exception(this.getClass().getName()+ " NewsSearchCod is null ");
        }
        
        //Call DMS to search for an user
        return this.getNewsResult(newsSearchCOD);
    }
    
    /*
     * This method searches a news in the database as per the search criteria
     * and populates the Collection with News COD.
     *
     * @param News news - News COD object
     * @returns Collection
     */
    public Collection getNewsResult(NewsSearchResult newsSearchCOD)
            throws Exception {
        boolean flag              = false;
        Vector newsList           = new Vector();
        StringBuffer query        = new StringBuffer();
        ResultSet rs              = null;
        Vector data               = null;
        Vector dataType           = null;
        DatabaseManager dbManager = null;
        
        //Build the query
        query.append("Select * From News");
        
        //Get the resultset
        dbManager = new DatabaseManager();
        rs = dbManager.executeQuery(query.toString());
        
        //Create a new COD and set the relevant values in it
        NewsSearchResult newsSearchResultCOD = new NewsSearchResult();
        
        while(rs.next()) {
            //Get news context and populate the value object
            newsSearchResultCOD.setNewsContent(rs.getString("NewsContent"));
            
            newsList.add(newsSearchResultCOD);
            newsSearchResultCOD = new NewsSearchResult();
        }
        
        return newsList;
    }
}