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Java does not handle IPv6 nameservers before 1.8.0_60. Upgrade to the latest JVM.
You try to parse a String that contains non-numeric characters to an int. The string must contain decimal characters only, optionally beginning with a + or - sign.
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java.lang.NumberFormatException: For input string: "quit"
There was a NumberFormatException. You can look that up in the API, but you can see what it means: a problem with the format of a number. It tried to read a number in a String, but found garbage instead. It even shows you the garbage: "quit", which of course isn't a number.