我有問題,我的小程序。它在applet查看器中正常工作,但在Web browser
它拋出一個異常。連接小程序<->數據庫通過瀏覽器
異常詳細信息:
`SQLException: No suitable driver found for jdbc:mysql://s46.eatj.com:3307/cmentarz
Exception in thread "AWT-EventQueue-2" java.lang.NullPointerException
at JDBC.LogIn(JDBC.java:49)
at AdminPanelLogIn$1.actionPerformed(AdminPanelLogIn.java:64)
at javax.swing.AbstractButton.fireActionPerformed(Unknown Source)
at javax.swing.AbstractButton$Handler.actionPerformed(Unknown Source)
at javax.swing.DefaultButtonModel.fireActionPerformed(Unknown Source)
at javax.swing.DefaultButtonModel.setPressed(Unknown Source)
at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(Unknown Source)
at java.awt.Component.processMouseEvent(Unknown Source)
at javax.swing.JComponent.processMouseEvent(Unknown Source)
at java.awt.Component.processEvent(Unknown Source)
at java.awt.Container.processEvent(Unknown Source)
at java.awt.Component.dispatchEventImpl(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(Unknown Source)
at java.awt.LightweightDispatcher.retargetMouseEvent(Unknown Source)
at java.awt.LightweightDispatcher.processMouseEvent(Unknown Source)
at java.awt.LightweightDispatcher.dispatchEvent(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(Unknown Source)
at java.awt.EventQueue.dispatchEventImpl(Unknown Source)
at java.awt.EventQueue.access$200(Unknown Source)
at java.awt.EventQueue$3.run(Unknown Source)
at java.awt.EventQueue$3.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source)
at java.awt.EventQueue$4.run(Unknown Source)
at java.awt.EventQueue$4.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source)
at java.awt.EventQueue.dispatchEvent(Unknown Source)
at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.run(Unknown Source)`
我已經使用JARmaker簽署我的jar文件。
我getConnection
方法代碼:
public Connection getConnection() throws SQLException {
try {
Class.forName("com.mysql.jdbc.Driver");
} catch (java.lang.ClassNotFoundException e) {
System.err.print("ClassNotFoundException: ");
System.err.println(e.getMessage());
}
try {
con = DriverManager.getConnection(url, userid, password);
} catch (SQLException ex) {
System.err.println("SQLException: " + ex.getMessage());
}
return con;
}
Userid
,password
和url
是正確的,因爲它在applet瀏覽器。
static String url = "jdbc:mysql://s46.eatj.com:3307/cmentarz";
所以,可能是什麼問題呢?
可能的重複:http://stackoverflow.com/questions/5616898/java-sql-sqlexception-no-suitable-driver-found-for-jdbcmicrosoftsqlserver –
另一方面。一個applet不應該直接訪問數據庫。而是強制它通過調解訪問的服務器工作,並限制它可以做的事情。 –