Question

IBM vs Oracle/Sun JDK, java.util.Timzone behaving differently ,

IBM JDK 1.5 vs Sun/Oracle JDK 1.6

import java.util.*;
class TimeTest {

public static void main(String args[]){

long now = System.currentTimeMillis();

System.out.println("EST : " + TimeZone.getTimeZone("EST").getOffset(now));
System.out.println("US/Eastern : " + TimeZone.getTimeZone("US/Eastern").getOffset(now));

}
}


***IBM JVM ouput

EST : -14400000
US/Eastern : -14400000

Oracle JVM

EST : -18000000
US/Eastern : -14400000
IBM JDK

java -version

java version "1.5.0"
Java(TM) 2 Runtime Environment, Standard Edition (build pxi32devifx-20090811 (SR10 +IZ56666+IZ56751))
IBM J9 VM (build 2.3, J2RE 1.5.0 IBM J9 2.3 Linux x86-32 j9vmxi3223-20090707 (JIT enabled)
J9VM - 20090706_38445_lHdSMr
JIT  - 20090623_1334_r8
GC   - 200906_09)
JCL  - 20090811


Oracle JDK

java -version

java version "1.6.0_24"                                         
Java(TM) SE Runtime Environment (build 1.6.0_24-b07)            
Java HotSpot(TM) Client VM (build 19.1-b02, mixed mode, sharing)

update , tested with IBM JDK 6 , it matches the ouput of oracle/sun
java -version
java version “1.6.0”
Java(TM) SE Runtime Environment (build pxi3260sr6ifix-20091015_01(SR6+152211+155930+156106))
IBM J9 VM (build 2.4, JRE 1.6.0 IBM J9 2.4 Linux x86-32 jvmxi3260sr6-20091001_43491 (JIT enabled, AOT enabled)
J9VM – 20091001_043491
JIT – r9_20090902_1330ifx1
GC – 20090817_AA)
JCL – 20091006_01

java TimeTest
EST : -18000000
US/Eastern : -14400000***

Answer 1

I think it’s safe to say your IBM JDK install has a much older timezone database that the other JDK installs. JDK 1.5 was released in 2004.