How do Java libraries manage dependencies and where are they obtained from during project build?

Java libraries and dependencies are usually managed using build systems and dependency managers such as Maven or Gradle.

How it works:

• Dependencies are described in a special file in the project (e.g., pom.xml for Maven or build.gradle for Gradle).
• When building the project, the system downloads the required libraries from remote repositories (e.g., Maven Central, JCenter).
• Dependencies can have their own dependencies (transitive), which are also automatically fetched.
• All downloaded artifacts are cached locally to avoid re-downloading.

Thus, during project build, the necessary libraries are fetched from remote repositories and connected automatically, simplifying version management and updates.