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Java Applet : inetAddress.getHostName() throws NullPointerException

I am trying to get the hostname. inetAddress.getHostName() works in Java Applications, but in the applet, it throws java.lang.NullPointerException.

How can I get Host-Name in an applet?

Solution 
  • java.net.InetAddress.getLocalHost().getHostName()

    and

    java.net.InetAddress.getLocalHost().getHostAddress()

    work in applets, only when the applet is signed. To sign, one can use jarsigner utility, which is included with the JDK.

    keytool -genkey -alias signFiles -keystore <gen_file> -keypass <key>-dname "cn=<somename>" -storepass <password>

jarsigner -keystore <gen_file> -storepass <password> -keypass <key> -signedjar <signed>.jar <unsigned>.jar signFiles

    All values within <...> must be replaced by appropriate values.