dbconnection.java

这是一个jsf上传下载文件的例子

package com.windy.fileupload;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.Statement;
import java.util.ArrayList;
import java.util.List;



public class DBConnection {
	public static Connection getConnection(){
		Connection conn=null;
		try {
			Class.forName("com.microsoft.jdbc.sqlserver.SQLServerDriver");
			conn=DriverManager.getConnection("jdbc:microsoft:sqlserver://127.0.0.1:1433;DatabaseName=pubs","sa","sa");
		} catch (Exception e) {
			// TODO: handle exception
		}
		return conn;
	}
	
	
	public List getFile(){
		List filelist=new ArrayList();
		try {
			Connection conn=getConnection();
			Statement stm=conn.createStatement();
			ResultSet rs=stm.executeQuery("select * from filelist");
			while(rs.next()){
				FileDescBO bo=new FileDescBO();
				bo.setFileid(rs.getInt("fileid"));
				bo.setFilename(rs.getString("filename"));
				bo.setPath(rs.getString("filepath"));
				filelist.add(bo);
			}
		} catch (Exception e) {
			e.printStackTrace();
		}
		return filelist;
	}
	
	
	public String getfilepath(int fileid){
		String filepath="";
		try {
			Connection conn=getConnection();
			String sql="select * from filelist where fileid=?";
			
			PreparedStatement stm=conn.prepareStatement(sql);
			stm.setInt(1,fileid);
			ResultSet rs=stm.executeQuery();
			while(rs.next()){
				filepath=rs.getString("filepath");
			}
		} catch (Exception e) {
			e.printStackTrace();
		}
		return filepath;
	}
}