Using scala scripts to check Java jar files

Here I attached two scripts that might help you working with jar files.

Have you tried to verify that a Class must exists in a lib directory that has few dozens jar files? For example I read from a forum that there is a ServerInfo.properties inside one of tomcat jar, so I run this:
$ scala searchjar.scala ServerInfo /opt/tomcat6/lib
/opt/tomcat6/lib/catalina.jar org/apache/catalina/util/ServerInfo.class

/opt/tomcat6/lib/catalina.jar org/apache/catalina/util/ServerInfo.properties
The script can walk over one or more directory and search all jar files for you.

The second thing I do once a while is I want to see the content of a text inside the jar. For the example above, I can run my second script like this:
$ scala displayjar.scala /opt/tomcat6/lib/catalina.jar org/apache/catalina/util/ServerInfo.properties
# Licensed to the Apache Software Foundation (ASF) under one or more

# contributor license agreements.  See the NOTICE file distributed with

# this work for additional information regarding copyright ownership.

# The ASF licenses this file to You under the Apache License, Version 2.0

# (the "License"); you may not use this file except in compliance with

# the License.  You may obtain a copy of the License at

#

#     http://www.apache.org/licenses/LICENSE-2.0

#

# Unless required by applicable law or agreed to in writing, software

# distributed under the License is distributed on an "AS IS" BASIS,

# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

# See the License for the specific language governing permissions and

# limitations under the License.



server.info=Apache Tomcat/6.0.18

server.number=6.0.18.0

server.built=Jul 22 2008 02:00:36
You can even run the displayjar.scala with just a jar file, and it default to print out the Manifest file content.

Hope these scripts are useful to you.

Views: 47

Attachments:

Happy 10th year, JCertif!

Notes

Welcome to Codetown!

Codetown is a social network. It's got blogs, forums, groups, personal pages and more! You might think of Codetown as a funky camper van with lots of compartments for your stuff and a great multimedia system, too! Best of all, Codetown has room for all of your friends.

When you create a profile for yourself you get a personal page automatically. That's where you can be creative and do your own thing. People who want to get to know you will click on your name or picture and…
Continue

Created by Michael Levin Dec 18, 2008 at 6:56pm. Last updated by Michael Levin May 4, 2018.

Looking for Jobs or Staff?

Check out the Codetown Jobs group.

 

Enjoy the site? Support Codetown with your donation.



InfoQ Reading List

Amazon Unveils Nova Act SDK and Expands Access to Advanced AI Models

Amazon has announced an expansion of its generative AI capabilities with the introduction of nova.amazon.com, a platform designed to give developers easier access to its foundation models. This includes the newly unveiled Amazon Nova Act, an AI model specifically trained to execute actions within web browsers.

By Robert Krzaczyński

GitLab Introduces GitLab Duo with Amazon Q

By Craig Risi

Presentation: Bringing a Product Mindset to an Infrastructure Platform Team

Stéphane Di Cesare discusses DKB's experience introducing a product mindset within their platform team, explaining their definition of a platform team, the rationale behind the shift, and their journey including challenges, goals, and key learnings around user value, platform definition, maturity models, and effective communication strategies for senior software developers and engineering leaders.

By Stéphane Di Cesare

Article: Beyond Chatbots: Architecting Domain-Specific Generative AI for Operational Decision-Making

This article explores the use of domain-specific Generative AI, models that understand operational constraints, real-world dynamics, and business rules to generate executable strategies, not just text descriptions. These models require significantly smaller datasets and fewer parameters, making them cost-effective while enabling AI-driven core business decision intelligence at scale.

By Abhishek Goswami

Bun 1.2 Improves Node Compatibility and Adds Postgres Client

The Bun team recently released Bun v1.2, with major progress regarding compatibility with Node.js, a key component of Bun’s value proposition. Bun 1.2 also now has a built-in S3 object storage API and a built-in Postgres client that comes in addition to the existing built-in SQLite client.

By Bruno Couriol

© 2025   Created by Michael Levin.   Powered by

Badges  |  Report an Issue  |  Terms of Service