java - 使用 JApplet 连接到 SQL

Question

我正在尝试使用 JApplet 连接到 SQL 数据库。但是，我得到一个 SecurityException:

com.mysql.jdbc.CommunicationsException: Communications link failure due to underlying exception: 

** BEGIN NESTED EXCEPTION ** 

java.net.SocketException
MESSAGE: java.security.AccessControlException: access denied ("java.net.SocketPermission" "162.243.229.150:3306" "connect,resolve")

STACKTRACE:

java.net.SocketException: java.security.AccessControlException: access denied ("java.net.SocketPermission" "162.243.229.150:3306" "connect,resolve")
    at com.mysql.jdbc.StandardSocketFactory.unwrapExceptionToProperClassAndThrowIt(StandardSocketFactory.java:407)
    at com.mysql.jdbc.StandardSocketFactory.connect(StandardSocketFactory.java:268)
    at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:271)
    at com.mysql.jdbc.Connection.createNewIO(Connection.java:2771)
    at com.mysql.jdbc.Connection.<init>(Connection.java:1555)
    at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:285)
    at java.sql.DriverManager.getConnection(DriverManager.java:664)
    at java.sql.DriverManager.getConnection(DriverManager.java:270)
    at me.nrubin29.cubesorter.MySQL.setup(MySQL.java:24)
    at me.nrubin29.cubesorter.MySQL.access$100(MySQL.java:8)
    at me.nrubin29.cubesorter.MySQL$1.run(MySQL.java:35)
    at java.lang.Thread.run(Thread.java:744)


** END NESTED EXCEPTION **



Last packet sent to the server was 1 ms ago.
    at com.mysql.jdbc.Connection.createNewIO(Connection.java:2847)
    at com.mysql.jdbc.Connection.<init>(Connection.java:1555)
    at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:285)
    at java.sql.DriverManager.getConnection(DriverManager.java:664)
    at java.sql.DriverManager.getConnection(DriverManager.java:270)
    at me.nrubin29.cubesorter.MySQL.setup(MySQL.java:24)
    at me.nrubin29.cubesorter.MySQL.access$100(MySQL.java:8)
    at me.nrubin29.cubesorter.MySQL$1.run(MySQL.java:35)
    at java.lang.Thread.run(Thread.java:744)
Exception in thread "Thread-38" java.lang.NullPointerException
    at me.nrubin29.cubesorter.MySQL$1.run(MySQL.java:38)
    at java.lang.Thread.run(Thread.java:744)

我试过使用 AccessController#doPrivileged ，但这没有帮助。如何授予对我的小程序使用套接字的权限？

Answer 1

查看这些:

java.net.SocketPermission in Applet

Can signed applets connect with a different host from which they originate?

如果你的小程序没有签名，你需要确认你的小程序
从它试图打开套接字的服务器加载。
然后这将起作用。