Commons Daemon

Last updated
Commons Daemon
Developer(s) Apache Software Foundation
Stable release
1.3.4 [1] / May 10, 2023;14 months ago (2023-05-10)
Repository
Written in Java, C
Operating system Cross-platform
Type Library
License Apache License 2.0
Website commons.apache.org/daemon

Commons Daemon, formerly known as JSVC, is a Java software library belonging to the Apache Commons Project.

Daemon provides a portable means of starting and stopping a Java Virtual Machine (JVM) that is running server-side applications. Such applications often have additional requirements compared to client-side applications. For example, the servlet container Tomcat 4 would need to serialize sessions and shutdown web applications before the JVM process terminates.

Daemon comprises 2 parts: a native library written in C that interfaces with the operating system, and the library that provides the Daemon API, written in Java.

There are two ways to use Commons Daemon: by implementing the daemon interface or by calling a class that provides the required methods for daemon. For example, Tomcat-4.1.x uses the daemon interface and Tomcat-5.0.x provides a class whose methods are called by JSVC directly.

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References

  1. "Daemon – Apache Commons Daemon Release Notes".