databaseoperation.java

《Java2程序设计实用教程(第2版)》课件

//【例11.2】  连接指定数据库并获得数据库属性信息。
//  数据库操作类

import java.sql.DriverManager;
import java.sql.Connection;
import java.sql.DatabaseMetaData;
import java.sql.SQLException;

public class DataBaseOperation
{
    private Connection connection;                         //数据库连接对象 

    public DataBaseOperation(String driver,String url, String user, String password)
        throws ClassNotFoundException,SQLException
                     //构造方法，连接指定数据库。4个参数分别指定JDBC驱动程序、数据库URL、用户名和密码
    {
        this.connection = null;
        Class.forName(driver);                             //指定JDBC驱动程序
        this.connection = DriverManager.getConnection(url,user,password); //连接指定数据库
    }

    public DataBaseOperation(String driver, String url) throws ClassNotFoundException,SQLException
    {
        this.connection = null;
        Class.forName(driver);
        this.connection = DriverManager.getConnection(url);
    }

    public void finalize() throws SQLException             //析构方法，关闭数据库连接
    {
        this.connection.close();
    }

    public String getDBAbout() throws SQLException         //获得所连接数据库的属性信息，返回字符串
    {
        String message = "";
        DatabaseMetaData dbmd = this.connection.getMetaData();
        message = "JDBC驱动程序：" + dbmd.getDriverName() +" "+ dbmd.getDriverVersion() + "\r\n" +
                  "JDBC URL：" + dbmd.getURL() + "\r\n" +
                  "数据库：" + dbmd.getDatabaseProductName() + "\r\n" +
                  "数据库版本：" + dbmd.getDatabaseProductVersion() + "\r\n"+
                  "用户名：" + dbmd.getUserName() + "\r\n";
        return message;
    }
}