Linux cmd to search for a class file among jars irrespective of jar path

Question

I want to search for a particular class file among many jar files without giving the location of each jar file.

Is this possible with a simple command?

I tried t

Answer 1

Linux, Walkthrough to find a class file among many jars.

Go to the directory that contains the jars underneath.

eric@dev /home/el/kafka_2.10-0.8.1.1/libs $ ls
blah.txt                             metrics-core-2.2.0.jar
jopt-simple-3.2.jar                  scala-library-2.10.1.jar
kafka_2.10-0.8.1.1-sources.jar       zkclient-0.3.jar
kafka_2.10-0.8.1.1-sources.jar.asc   zookeeper-3.3.4.jar
log4j-1.2.15.jar

I'm looking for which jar provides for the Producer class.

Understand how the for loop works:

eric@dev /home/el/kafka_2.10-0.8.1.1/libs $ for i in `seq 1 3`; do
> echo $i
> done
1
2
3

Understand why find this works:

eric@dev /home/el/kafka_2.10-0.8.1.1/libs $ find . -name "*.jar"
./slf4j-api-1.7.2.jar
./zookeeper-3.3.4.jar
./kafka_2.10-0.8.1.1-javadoc.jar
./slf4j-1.7.7/osgi-over-slf4j-1.7.7-sources.jar

You can pump all the jars underneath into the for loop:

eric@dev /home/el/kafka_2.10-0.8.1.1/libs $ for i in `find . -name "*.jar"`; do
> echo $i
> done

./slf4j-api-1.7.2.jar
./zookeeper-3.3.4.jar
./kafka_2.10-0.8.1.1-javadoc.jar
./kafka_2.10-0.8.1.1-sources.jar

Now we can operate on each one:

Do a jar tf on every jar and cram it into blah.txt:

for i in `find . -name "*.jar"`; do echo $i; jar tf $i; done > blah.txt

Inspect blah.txt, it's a list of all the classes in all the jars. You can search that file for the class you want, then look for the jar that came before it, that's the one you want.