votedao.java

教你一天学会struts

package com.soft136.strutsoneday.dao;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

import javax.sql.rowset.CachedRowSet;

import com.sun.rowset.CachedRowSetImpl;

public class VoteDAO {

	public CachedRowSet getVotes() throws SQLException, ClassNotFoundException {
		Connection conn = null;
		PreparedStatement ps = null;
		ResultSet rs = null;
		try {
			Class.forName("com.mysql.jdbc.Driver");
			conn = DriverManager.getConnection(
					"jdbc:mysql://localhost:3306/soft136", "root", "123456");
			ps = conn.prepareStatement("SELECT VOTEID,NAME,SUM FROM VOTE");
			rs = ps.executeQuery();
			CachedRowSet crs = new CachedRowSetImpl();
			crs.populate(rs);
			return crs;
		} finally {
			if (ps != null) {
				ps.close();
			}
			if (conn != null) {
				conn.close();
			}
		}
	}

	public void vote(int voteId) throws SQLException, ClassNotFoundException {
		Connection conn = null;
		PreparedStatement ps = null;
		try {
			Class.forName("com.mysql.jdbc.Driver");
			conn = DriverManager.getConnection(
					"jdbc:mysql://localhost:3306/soft136", "root", "123456");
			ps = conn
					.prepareStatement("UPDATE VOTE SET SUM=SUM+1 WHERE VOTEID=?");
			ps.setInt(1, voteId);
			ps.executeUpdate();
		} finally {
			if (ps != null) {
				ps.close();
			}
			if (conn != null) {
				conn.close();
			}
		}
	}
}