高手帮我看看这是什么原因呀
论坛里找了一段APPLET连接数据库的程序,编译却出现这些错误,是那里出了问题?
odbc.java:10:cannot resolve symbol
symbol;varlable lightGray
this.setBackground(Color.lightGray);
程序如下:
import java.awt.*;
import java.applet.*;
import java .sql.*;
public class odbc extends Applet {
public void init() {
resize(400,300);
}
public void paint(Graphics g){ //此方法用于显示输出
this.setBackground(Color.lightGray ); //定义背景颜色
this.setForeground(Color.red); //定义前景颜色
String url="jdbc:odbc:sheji";
String ls_1="select * from HistoryAlarm";
try{ //异常处理模块
Class.forName("sun.jdbc.odbc.JdbcOdbcDriver"); //加载驱动程序
//建立连接
Connection con=DriverManager.getConnection(url);
//执行SQL
Statement stmt=con.createStatement();
ResultSet result=stmt.executeQuery(ls_1); //返回结果
g.drawString("AlarmNumber",40,40);
g.drawString("AlarmLevel",80,40);
int i=10;
while(result.next()){ //取各个字段的值
g.drawString(result.getString(1),40,60+i);
g.drawString(result.getString(2),80,60+i);
g.drawString(result.getString(3),160,60+i);
i+=20;
}
//关闭连接
result.close();
stmt.close();
con.close();
}
//捕获异常
catch(SQLException ex){
System.out.println(ex.toString());
}
catch(java.lang.Exception ex){
System.out.println(ex.toString());
}
}
}
当屏蔽掉设置颜色的语句后,编译通过,但在嵌入HTML中后,却又出现错误:
java.security.AccessControlException: access denied (java.lang.RuntimePermission accessClassInPackage.sun.jdbc.odbc)
HEAD>
<TITLE>HTML Test Page</TITLE>
</HEAD>
<BODY>
<table width=100%>
<tr>
<td>
Applet2 will appear below in a Java enabled browser.<BR>
<APPLET CODE = "odbc.class" WIDTH = 400 HEIGHT = 300 HSPACE = 0 VSPACE = 0 ALIGN = middle>
</APPLET>
</td>
</tr>
</table>
</BODY>
</HTML>
我的数据源设置没问题,sun.jdbc.odbc.JdbcOdbcDriver驱动也应该没问题,因为我用java application实现没出错。究竟是那出了问题呀!