databasebean.java

简单的J2EE构架

package bean;

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

import entity.User;

public class DataBaseBean {

	public void saveUser(String username, String password) {
		String sql = "insert into t_user values('" + username + "', '"
				+ password + "')";

		Connection conn = null;
		Statement stmt = null;

		try {
			Class.forName("oracle.jdbc.driver.OracleDriver");
			conn = DriverManager.getConnection(
					"jdbc:oracle:thin:@220.191.245.237:1521:zhejiang", "WS1",
					"12345678");
			stmt = conn.createStatement();
			stmt.executeUpdate(sql);

		} catch (ClassNotFoundException e) {

			e.printStackTrace();
		} catch (SQLException e) {
			e.printStackTrace();
		} finally {
			if (stmt != null) {
				try {
					stmt.close();
					stmt = null;
				} catch (SQLException e) {
					e.printStackTrace();
				}
			}

			if (conn != null) {
				try {
					conn.close();
					conn = null;
				} catch (SQLException e) {
					e.printStackTrace();
				}

			}
		}
	}

	public User getUser(String tempUsername) {
		String sql = "select username, password from t_user where username = '" + tempUsername + "'" ;

		Connection conn = null;
		Statement stmt = null;
		ResultSet rs = null;
		try {
			Class.forName("oracle.jdbc.driver.OracleDriver");
			conn = DriverManager.getConnection(
					"jdbc:oracle:thin:@220.191.245.237:1521:zhejiang", "WS1",
					"12345678");
			stmt = conn.createStatement();
			rs = stmt.executeQuery(sql);

			if (rs.next()) {
				String username = rs.getString("username");
				String password = rs.getString("password");
				User user = new User(username, password);
				return user;
			}
			return null;

		} catch (ClassNotFoundException e) {

			e.printStackTrace();
			return null;
		} catch (SQLException e) {
			e.printStackTrace();
			return null;
		} finally {
			if (stmt != null) {
				try {
					stmt.close();
					stmt = null;
				} catch (SQLException e) {
					e.printStackTrace();
				}
			}

			if (conn != null) {
				try {
					conn.close();
					conn = null;
				} catch (SQLException e) {
					e.printStackTrace();
				}

			}
		}
	}

}