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: 57

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

Agoda Builds Multimodal Content System to Bridge Images and Reviews in Travel Discovery

Agoda Multimodal Content Systemhttps://example.com/agoda-multimodal-content-systemAgoda unifies hotel images and guest reviews using a shared topic taxonomy, enabling multimodal retrieval across 700M+ images and multilingual reviews with offline enrichment and low-latency serving.

By Leela Kumili

Presentation: Powering the Future: Building Your GenAI Infrastructure Stack

Merrin Kurian shares the architectural blueprints and organizational processes behind Intuit’s AI transformation. She explains the "fixed, flexible, free" framework used to scale GenOS across 8,000 developers, enabling 3,500+ production experiments. She discusses critical agent failure modes, the "LLM-as-a-judge" evaluation strategy, and how to build "tool-ready" APIs for the future.

By Merrin Kurian

TanStack Details Sophisticated npm Supply Chain Attack That Compromised 42 Packages

TanStack has released a detailed postmortem describing a sophisticated supply-chain attack that compromised 42 npm packages and published 84 malicious package versions in just six minutes, exposing developers and CI/CD systems to credential theft and malware propagation.

By Craig Risi

Article: Kernel-Level Ground Truth: Why eBPF is Replacing User-Space Agents for Security Observability

eBPF is emerging as a preferred method for security observability over traditional user-space agents. By attaching probes directly to the Linux kernel's syscall interface, it provides consistent visibility even during container-level compromises. eBPF reduces security-related CPU consumption and limits data volume by performing filtering at the kernel level, enhancing operational efficiency.

By Niranjan Sharma

Vite Version 8: Unified Rust-Based Bundler and Up to 30x Faster Builds

Vite 8.0 introduces a significant architectural change, migrating from a dual-bundler setup to a single Rust-based bundler called Rolldown. This update enhances build speeds, reporting reductions from 46 seconds to 6 seconds in some projects. The release includes developer experience improvements and maintains compatibility with the existing plugin ecosystem.

By Daniel Curtis

© 2026   Created by Michael Levin.   Powered by

Badges  |  Report an Issue  |  Terms of Service