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lein:tldr:9703f
The command "lein uberjar" is used in the context of the Clojure programming language and Leiningen, which is a popular build tool for Clojure projects.
When you run "lein uberjar" from the command line, it instructs Leiningen to build a standalone, executable JAR file ("uberjar") for your Clojure project. An Uberjar is an artifact that contains all the necessary dependencies, including your project's code, as well as the Clojure runtime. This makes it easier to distribute and run your Clojure application on different machines without worrying about missing dependencies.
The "lein uberjar" command triggers a series of actions performed by Leiningen:
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Leiningen looks for the project.clj file in the current directory, which contains metadata and configuration for your Clojure project. It reads this file to determine the project's dependencies and other build-related settings.
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Leiningen then resolves the project's dependencies, downloading any necessary libraries from remote repositories.
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After resolving the dependencies, Leiningen compiles the Clojure source code from the src/ directory into .class files.
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At this point, Leiningen starts packaging the JAR file. It creates a temporary directory, copies the compiled code into it, and adds the project's dependencies as well. These dependencies are included as JAR files or as directories, depending on their packaging format. The dependencies are copied into the JAR file's classpath so that they can be accessed by your project's code at runtime.
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Finally, Leiningen generates the "uberjar". It packages all the compiled code and the dependencies into a single JAR file. By default, this JAR file is named
- .jar and is saved in the target/ directory.
Once the "lein uberjar" command completes, you can distribute the generated Uberjar and run it on any machine with Java installed by executing the command "java -jar