I forget things. A lot. I need a to do list tracker that works with me. So I wrote one. I, being me, used the technologies I use the most to make this happen: bash and git.
Monthly Archives: September 2011
JSS Sockets and HttpClient
The Java bindings for the Network Security Services (NSS) Library is called JSS. NSS provides a key management scheme that is different enough from both standard Java and OpenSSL that trying to do standard Java Socket operations using the Apache HttpClient requires a little bit of extra work.
Group Delegation in Unix
One thing that is missing in traditional Unix systems is the ability to let a non root user manage group membership. Unix was built around several simple concepts. One of those was: everything is a file. Using this principle, we can specify how group delegation would have worked.
Talking to Dogtag PKI via curl
As I dig deeper into the Dogtag code, I find I want to be able to talk to the web server from the command line the same way I did when for IPA work. Since Dogtag is certificate based, and the version of curl included in Fedora has NSS build in, I used the NSS/Certificate approach.
Finding Java Classes
I’m back on a Java project. Been a while, and I want to capture some of the tricks I’m using.
Right now, I’m just trying to import the project into eclipse. Seems that the current team members don’t use it. I’m an IDE kind of guy, at least when it comes to Java.
Building the .classpath file can be tricky. However, since I know that I have a good build, and that this project it a good participant in the Fedora build process, I have the advantage of knowing that my packages reside in /usr/share/java. Still, all eclipse gives me is a set of classes that it can’t find. how to find them?
This project uses CMake. I could look for all of the Jar files in the CMakeLists.txt files, and I might do that in the future. However, a trick I’ve developed in the past has come in handy.
class2path(){ echo $1 | sed 's!\.!\/!g' } JDIR=/usr/share/java make_alljars(){ for JAR in `find /usr/share/java -name \*.jar -type f ` do for CLASS in `jar -tf $JAR | grep \.class` do echo $JAR $CLASS done done > /tmp/alljars.txt }
First, the make_alljars function creates a map in (value key) order. The value is the Jar file name, and the key is the class name. To fine a Jar file that contains a given class (in this example netscape.ldap.LDAPConnection) , run:
grep `class2path netscape.ldap.LDAPConnection` /tmp/alljars.txt
And the output is
/usr/share/java/ldapjdk.jar netscape/ldap/LDAPConnection$ResponseControls.class /usr/share/java/ldapjdk.jar netscape/ldap/LDAPConnection.class
This works really well with eclipse, in that the error messages have the name of the class. You can then just highlight the class name, paste it into the command line in place of the class I have above, and when you get the Jar file name, you can highlight to save to the clipboard. From The right click context menu pick Java Build Path and then Add External Archive and then paste the whole path in.
Java as a scripting language
When developing in Python or Perl, it is very common to start with an executable script, and to edit/run/edit/run. Java is slowed down by the cycle of edit/compile/run. Here’s a proof of concept of coding in Java like you do in Python.