Message9893

Here's what I get with pretty much the same Ubuntu setup as you have:

$ java -jar dist/jython-installer.jar -s -d $HOME/Software/jython-2.7-rc2
Performing silent installation
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Generating start scripts ...
Installing pip and setuptools
 90 %
*sys-package-mgr*: processing new jar, '/home/jbaker/Software/jython-2.7-rc2/jython.jar'
*sys-package-mgr*: processing new jar, '/usr/lib/jvm/java-7-openjdk-amd64/jre/lib/resources.jar'
*sys-package-mgr*: processing new jar, '/usr/lib/jvm/java-7-openjdk-amd64/jre/lib/rt.jar'
*sys-package-mgr*: processing new jar, '/usr/lib/jvm/java-7-openjdk-amd64/jre/lib/jsse.jar'
*sys-package-mgr*: processing new jar, '/usr/lib/jvm/java-7-openjdk-amd64/jre/lib/jce.jar'
*sys-package-mgr*: processing new jar, '/usr/lib/jvm/java-7-openjdk-amd64/jre/lib/charsets.jar'
*sys-package-mgr*: processing new jar, '/usr/lib/jvm/java-7-openjdk-amd64/jre/lib/rhino.jar'
*sys-package-mgr*: processing new jar, '/usr/lib/jvm/java-7-openjdk-amd64/jre/lib/ext/localedata.jar'
*sys-package-mgr*: processing new jar, '/usr/lib/jvm/java-7-openjdk-amd64/jre/lib/ext/sunpkcs11.jar'
*sys-package-mgr*: processing new jar, '/usr/lib/jvm/java-7-openjdk-amd64/jre/lib/ext/sunjce_provider.jar'
*sys-package-mgr*: processing new jar, '/usr/lib/jvm/java-7-openjdk-amd64/jre/lib/ext/zipfs.jar'
*sys-package-mgr*: processing new jar, '/usr/lib/jvm/java-7-openjdk-amd64/jre/lib/ext/java-atk-wrapper.jar'
*sys-package-mgr*: processing new jar, '/usr/lib/jvm/java-7-openjdk-amd64/jre/lib/ext/icedtea-sound.jar'
*sys-package-mgr*: processing new jar, '/usr/lib/jvm/java-7-openjdk-amd64/jre/lib/ext/dnsns.jar'
Ignoring indexes: https://pypi.python.org/simple/
Downloading/unpacking setuptools
Downloading/unpacking pip
Installing collected packages: setuptools, pip
Successfully installed setuptools pip
Cleaning up...
 100 %
Congratulations! You successfully installed Jython 2.7rc2+ to directory /home/jbaker/Software/jython-2.7-rc2.
jbaker@thought:~/jythondev/jython27$ cd ~/Software/jython-2.7-rc2/
jbaker@thought:~/Software/jython-2.7-rc2$ bin/jython -m ensurepip
Ignoring indexes: https://pypi.python.org/simple/
Requirement already satisfied (use --upgrade to upgrade): setuptools in ./Lib/site-packages
Requirement already satisfied (use --upgrade to upgrade): pip in ./Lib/site-packages
Cleaning up...

So no harm in trying to do the second ensurepip. Arguably it should say "Finished" as the last line, but that's a minor detail in ensurepip itself.

$ lsb_release -a
LSB Version:    core-2.0-amd64:core-2.0-noarch:core-3.0-amd64:core-3.0-noarch:core-3.1-amd64:core-3.1-noarch:core-3.2-amd64:core-3.2-noarch:core-4.0-amd64:core-4.0-noarch
Distributor ID: Ubuntu
Description:    Ubuntu 14.10
Release:        14.10
Codename:       utopic

$ java -version
java version "1.7.0_75"
OpenJDK Runtime Environment (IcedTea 2.5.4) (7u75-2.5.4-1~utopic1)
OpenJDK 64-Bit Server VM (build 24.75-b04, mixed mode)

I also tried this with Oracle Java 7 and Java 8 with the same results.

So putting this in the "works for me" category, but we will see if anyone else can reproduce.