java.sql.SQLException:没有为jdbc:derby找到合适的驱动程序:

Question

我是jdbc的初学者...我在运行此代码时遇到问题:

这段代码使用appache derby,为了使它工作,我首先启动了derby服务器..

      java -jar "C:\Program Files\Sun\JavaDB\lib\derbyrun.jar" server start

然后启动程序

      java -classpath derbyclient.jar -jar TestDB.jar

我设置了类路径C:\ Program Files\Sun\JavaDB\lib\derby.jar

我总是得到那个例外

java.sql.SQLException:没有为jdbc找到合适的驱动程序:derby:// localhost:1527/BOOKDB; java.sql.DriverManager.getConnection(DriverManager.java:602)中的create = true at java.sql.DriverManager.getConnection( DriverManager.java:185)位于TestDB.runTest(TestDB.java:20)的TestDB.getConnection(TestDB.java:63)TestDB.main(TestDB.java:11)

import java.sql.*;
import java.io.*;
import java.util.*;


class TestDB
{
   public static void main(String args[])
   {
      try
      {
         runTest();
      }
      catch (SQLException ex)
      {
         for (Throwable t : ex)
            t.printStackTrace();
      }
      catch (IOException ex)
      {
         ex.printStackTrace();
      }
   }

   public static void runTest() throws SQLException, IOException
   {
      Connection conn = getConnection();
      try
      {
         Statement stat = conn.createStatement();

         stat.executeUpdate("CREATE TABLE Greetings (Message CHAR(20))");
         stat.executeUpdate("INSERT INTO Greetings VALUES ('Hello, World!')");

         ResultSet result = stat.executeQuery("SELECT * FROM Greetings");
         if (result.next())
            System.out.println(result.getString(1));
         result.close();
         stat.executeUpdate("DROP TABLE Greetings");
      }
      finally
      {
         conn.close();
      }
   }

   public static Connection getConnection() throws SQLException, IOException
   {
      Properties props = new Properties();
      FileInputStream in = new FileInputStream("database.properties");
      props.load(in);
      in.close();

      String drivers = props.getProperty("jdbc.drivers");
      if (drivers != null) System.setProperty("jdbc.drivers", drivers);
      String url = props.getProperty("jdbc.url");
      String username = props.getProperty("jdbc.username");
      String password = props.getProperty("jdbc.password");

      return DriverManager.getConnection(url, username, password);
   }
}

Answer 1

java使用-jar和-classpath参数调用命令时,将-classpath忽略该参数.请参阅Java启动程序的文档.

你可以使用:

在Unix/Linux:

java -classpath derbyclient.jar:TestDB.jar TestDB

视窗:

java -classpath derbyclient.jar;TestDB.jar TestDB

或者制作一个将derbyclient.jar添加到类路径的清单.