Libraries

• These are jars that are used in other java applications.

• A Java library is Java-virtual-machine-based bytecode which encodes the classes in the library.

• A library is shared via a "jar" file (essentially just a zip file of the classes) and, once it is referenced in your classpath is available to be invoked by other classes (including from other libraries).

Creating a library

• Using gradle

  • https://guides.gradle.org/building-java-libraries/

• Using maven

deploying to a artifact repository

• Examples of artifact repository

  • mvn repository

  • jfrog artifactory

Using a library

• Via dependency management tool ie mavan, gradle

• Downloading the jar, and adding it to the class path manually

Monkey patching

• Not advised

• You can augment an existing class. You can add methods and attributes.

• You can modify a method of an existing class.

Links

• https://www.beyondjava.net/what-about-monkey-patching-is-it-as-dangerous-as-they-say

Design

• https://www.oracle.com/corporate/features/library-in-java-best-practices.html