东软学习，sql工具类

package mode09;

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

public class DBUtil {

	static Connection connection = null;
	static Statement statement = null;
	static ResultSet resultSet = null;

	private static Connection getConnection() throws ClassNotFoundException,
			SQLException {
		// TODO Auto-generated method stub
		String driverName = "oracle.jdbc.driver.OracleDriver";
		                 
		String url = "jdbc:oracle:thin:@localhost:1521:oracle";
		String userName = "scott";
		String userPwd = "tiger";
		Class.forName(driverName);
		if (connection == null || connection.isClosed()) {
			connection = DriverManager.getConnection(url, userName, userPwd);
		}
		return connection;
	}

	private static int executeUpdate(String sql) throws ClassNotFoundException,
			SQLException {
		// TODO Auto-generated method stub
		int result = 0;
		getConnection();
		statement = connection.createStatement();
		result = statement.executeUpdate(sql);
		closeAll();
		return result;
	}

	private static void closeAll() throws SQLException {
		// TODO Auto-generated method stub

		if (!resultSet.isClosed()) {
			resultSet.close();
		}
		if (!statement.isClosed()) {
			statement.close();
		}
		if (!connection.isClosed()) {
			connection.close();
		}
	}
	private static ResultSet executeQuery(String sql) throws ClassNotFoundException, SQLException {
		// TODO Auto-generated method stub

		getConnection();
		statement = connection.createStatement();
		resultSet = statement.executeQuery(sql);
		closeAll();
		return resultSet;
		
		
	}
	private static int PreparedStatement(String sql) throws ClassNotFoundException, SQLException {
		// TODO Auto-generated method stub
		sql = "update emp set ename = ? where empno = 7369";
		getConnection();
		java.sql.PreparedStatement preparedStatement = connection.prepareStatement(sql);
		preparedStatement.setString(1, "Gink");
		int i =  preparedStatement.executeUpdate();
		return i;
	}
	public static void main(String[] args) throws ClassNotFoundException, SQLException {

		int i = DBUtil.PreparedStatement("dsv");
		
		if (i == 1) {
			System.out.println("成功");
		}
		else{
			System.out.println("N");
		}
//		while (rs.next()) {
//			System.out.print(rs.getInt("EMPNO")+"\t");
//			System.out.print(rs.getString("ENAME")+"\t");
//			System.out.print(rs.getString("JOB")+"\t");
//			System.out.print(rs.getInt("MGR")+"\t");
//			System.out.print(rs.getDate("HIREDATE")+"\t");
//			System.out.print("\n+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++\n");
//		}
	}
}