FULL PRODUCT VERSION :
java 9.0.4
Java(TM) SE Runtime Environment (build 9.0.4+11)
Java HotSpot(TM) 64-Bit Server VM (build 9.0.4+11, mixed mode)


ADDITIONAL OS VERSION INFORMATION :
Red Hat Enterprise Linux Server release 7.4 (Maipo)
Linux alexrhel7test.mpr.org 3.10.0-693.21.1.el7.x86_64 #1 SMP Fri Feb 23 18:54:16 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux

EXTRA RELEVANT SYSTEM CONFIGURATION :
Brand new VM, nothing unique as far as the configuration.
Installed using Redhat 7.4 minimal

A DESCRIPTION OF THE PROBLEM :
It seems that java doesn't support a format of the TZ environment variable in Linux. On http://www.gnu.org/software/libc/manual/html_node/TZ-Variable.html at the bottom the of document, the format :characters is defined.

Java doesn't seem properly read the variable if TZ is set to a file path. When the TZ variable is set to :/etc/localtime, the java timezone doesn't properly honor daylight savings time and all time operations are an hour off.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
I installed a fresh RHEL7.4 minimal system, updated it with yum update and rebooted.
During installation I set the timezone to American/Chicago
Then I downloaded jdk-9.0.4_linux-x64_bin.rpm from Oracle's website
Then I ran "yum install jdk-9.0.4_linux-x64_bin.rpm"

I used this sample java code in a file called GetDate.java:
import java.util.Date;

class GetDate {
  /** Print a hello message */
  public static void main(String[] args) {
    Date today = new Date();
    System.out.println(today);
  }
}

Then I ran "javac GetDate.java"
Then I ran "java GetDate"

The output was
$ java GetDate
Wed Mar 21 14:48:35 CDT 2018

If I create a timezone environment variable:
export TZ=:/etc/localtime

Then run the java command again, I get different result, one hour off:
$ java GetDate
Wed Mar 21 13:50:04 GMT-06:00 2018

If I run the local date command, I get the correct time, even with the environment variable
$ date
Wed Mar 21 14:50:06 CDT 2018


$ ls -hla /etc/localtime
lrwxrwxrwx. 1 root root 37 Mar 21 13:28 /etc/localtime -> ../usr/share/zoneinfo/America/Chicago

If I unset the TZ environment variable, it works
$ unset TZ
$ java GetDate
Wed Mar 21 14:52:38 CDT 2018

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
I expect the test script to show the correct time with the correct hour based on daylight savings.
ACTUAL -
Instead I see time that is an hour off.

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
import java.util.Date;

class GetDate {
  /** Print a hello message */
  public static void main(String[] args) {
    Date today = new Date();
    System.out.println(today);
  }
}
---------- END SOURCE ----------

CUSTOMER SUBMITTED WORKAROUND :
Unsetting the TZ variable works.
Setting the TZ variable to "American/Chicago" works.