channellist.java

JAVA邮件系统

import java.io.*;
import java.text.*;
import java.util.*;
import java.sql.*;

/**
 * 
 *
 * @author Chen Xin Wu
 */
 
 public class ChannelList
 {
	static int channelNum=0;
	static Channel[] channelList;
	
	ChannelList(){
		channelNum=0;
		makeChannel();
	}
	
	public static Channel[] makeChannel(){
		 channelList=new Channel[100];
		// 初始化频道
		DBOperater DB = new DBOperater("Channel");
		String queryString;
		try 
		{
			queryString = "select * from channel";				
   	    	ResultSet rs = DB.executeQuery(queryString);
   	    	Channel temp;
   	    	String name,id,type,module;
	   	    if(rs==null){
				DB.close();
				return null;
			}	
	   	    while(rs.next())
	   	    {
	   	    	name = CommonMethods.getFieldValue (rs,"channelname");
	   	    	id = CommonMethods.getFieldValue (rs,"channelid");
	   	    	type = CommonMethods.getFieldValue (rs,"type");
	   	    	module = CommonMethods.getFieldValue (rs,"modulename");
				if( module ==null )
					continue;
					
				try{
					temp = (Channel)(Class.forName(module).newInstance());
				}catch(Exception e)
				{
					temp=null;
					continue;
				}
	   	    	temp.setChannelName(name);
	   	    	temp.setChannelID(id);
	   	    	temp.setChannelType(type);
	   	    	temp.setChannelModule(module);
	   	    	channelList[channelNum] = temp;
	   	    	channelNum++;
	   	    }
	   	    	
			
		} catch(Exception ex) {
			System.err.println("ReplaceEngine SQLException: " + ex.getMessage());
		}
		DB.close();
		return channelList;
	}
	
 	
	
	public static Channel searchChannel(String name)
	{
		int i;
		if(name == null)
			return null;
		name = name.trim ();
		for(i=0;i<channelNum;i++)
		{
			if(channelList[i].getChannelID().compareTo (name)==0)
				return channelList[i];
		}
		return null;
	}
	public static int getChannelNum() { return channelNum; }
	public static Channel getChannelAt(int i) { return channelList[i]; }
 }