This can be reproduced with both JDK and JRE scripts.

To reproduce download JDK or JRE self-extracting shell script and follow below steps.

1)Install JDK or JRE in a directory /tmp
2)Repeat Step 1 in the same directory /tmp
3)Script will prompt [y]es, [n]o, [A]ll, [N]one, [r]ename:
4)Type 'None'
5)Result is it will install subset of files.

replace jdk1.6.0/db/lib/derbyclient.jar? [y]es, [n]o, [A]ll, [N]one, [r]ename: None
  inflating: jdk1.6.0/jre/lib/ext/localedata.pack
  inflating: jdk1.6.0/jre/lib/rt.pack
  inflating: jdk1.6.0/jre/lib/jsse.pack
  inflating: jdk1.6.0/jre/lib/charsets.pack
  inflating: jdk1.6.0/jre/lib/plugin.pack
  inflating: jdk1.6.0/jre/lib/javaws.pack
  inflating: jdk1.6.0/jre/lib/deploy.pack
  inflating: jdk1.6.0/lib/tools.pack
Creating jdk1.6.0/jre/lib/rt.jar
Creating jdk1.6.0/jre/lib/jsse.jar
Creating jdk1.6.0/jre/lib/charsets.jar
Creating jdk1.6.0/lib/tools.jar
Creating jdk1.6.0/jre/lib/ext/localedata.jar
Creating jdk1.6.0/jre/lib/plugin.jar
Creating jdk1.6.0/jre/lib/javaws.jar
Creating jdk1.6.0/jre/lib/deploy.jar

Done.