连接数据库的DBUtils工具类

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

public class DBUtils {
	static{
		try {
			Class.forName("oracle.jdbc.driver.OracleDriver");
		} catch (ClassNotFoundException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}
	public static Connection getConnection() throws SQLException{
		String url = "jdbc:oracle:thin:@10.25.116.138:1521:orcl";
		Connection conn = DriverManager.getConnection(url, "scott", "tiger");
		return conn;
	}
	public static void close(PreparedStatement ps){
		if(ps != null){
			try {
				ps.close();
			} catch (SQLException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
		}
	}
	public static void close(ResultSet rs){
		if(rs != null){
			try {
				rs.close();
			} catch (SQLException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
		}
	}
	public static void close(Connection conn){
		if(conn != null){
			try {
				conn.close();
			} catch (SQLException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
		}
	}
	
	public static void main(String[] args) {
		
		String answer = "";
		try {
			Connection conn = DBUtils.getConnection();
			StringBuilder sql = new StringBuilder("select name from t_emp");
			PreparedStatement ps = conn.prepareStatement(sql.toString());
			ResultSet rs = ps.executeQuery();
			while (rs.next()) {
				answer += rs.getString("name");
			}
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		System.out.println("answer = " + answer);
	}
}