From d3c7747fe2a3b38a14e6edcb4cab68f6d6d2ba27 Mon Sep 17 00:00:00 2001 From: Decebal Suiu Date: Wed, 8 Mar 2017 21:45:42 +0200 Subject: [PATCH] Add 'Custom PluginManager' section in readme --- README.md | 53 +++++++++++++++++++ .../ro/fortsoft/pf4j/JarPluginManager.java | 2 +- 2 files changed, 54 insertions(+), 1 deletion(-) diff --git a/README.md b/README.md index 8ad5ace..455f8fc 100644 --- a/README.md +++ b/README.md @@ -265,6 +265,59 @@ __PluginStateListener__ defines the interface for an object that listens to plug Your application, as a PF4J consumer, has full control over each plugin (state). So, you can load, unload, enable, disable, start, stop and delete a certain plugin using PluginManager (programmatically). +Custom PluginManager +-------------------------- +To create a custom plugin manager you could: +* implements `PluginManager` interface (create a plugin manager from scratch) +* modifies some aspects/behaviors of built-in implementations (`DefaultPluginManager`, `JarPluginManager`) +* extends `AbstractPluginManager` class + +`JarPluginManager` is a `PluginManager` that loads plugin from a jar file. Actually, a plugin is a fat jar, a jar which contains classes from all the libraries, +on which your project depends and, of course, the classes of current project. +`AbstractPluginManager` adds some glue that help you to create quickly a plugin manager. All you need to do is to implement some factory methods. +PF4J uses in many places the factory method pattern to implement the dependency injection (DI) concept in a manually mode. +See below the abstract methods for `AbstractPluginManager`: + +```java +public abstract class AbstractPluginManager implements PluginManager { + + protected abstract PluginRepository createPluginRepository(); + protected abstract PluginFactory createPluginFactory(); + protected abstract ExtensionFactory createExtensionFactory(); + protected abstract PluginDescriptorFinder createPluginDescriptorFinder(); + protected abstract ExtensionFinder createExtensionFinder(); + protected abstract PluginStatusProvider createPluginStatusProvider(); + protected abstract PluginLoader createPluginLoader(); + + // other non abstract methods + +} +``` + +`DefaultPluginManager` contributes with "default" components (`DefaultExtensionFactory`, `DefaultPluginFactory`, `DefaultPluginLoader`, ...) to `AbstractPluginManager`. +Most of the times it's enough to extends `DefaultPluginManager` and to supply your custom components. As example, I will show you the implementation for `JarPluginManager`: + +```java +public class JarPluginManager extends DefaultPluginManager { + + @Override + protected PluginRepository createPluginRepository() { + return new JarPluginRepository(getPluginsRoot(), isDevelopment()); + } + + @Override + protected PluginDescriptorFinder createPluginDescriptorFinder() { + return isDevelopment() ? new PropertiesPluginDescriptorFinder() : new JarPluginDescriptorFinder(); + } + + @Override + protected PluginLoader createPluginLoader() { + return new JarPluginLoader(this, pluginClasspath); + } + +} +``` + Development mode -------------------------- PF4J can run in two modes: **DEVELOPMENT** and **DEPLOYMENT**. diff --git a/pf4j/src/main/java/ro/fortsoft/pf4j/JarPluginManager.java b/pf4j/src/main/java/ro/fortsoft/pf4j/JarPluginManager.java index b2442ff..bc66f03 100644 --- a/pf4j/src/main/java/ro/fortsoft/pf4j/JarPluginManager.java +++ b/pf4j/src/main/java/ro/fortsoft/pf4j/JarPluginManager.java @@ -30,7 +30,7 @@ import java.util.jar.JarFile; import java.util.jar.Manifest; /** - * It's a {@link PluginManager} that load plugin from a jar file. + * It's a {@link PluginManager} that loads plugin from a jar file. * Actually, a plugin is a fat jar, a jar which contains classes from all the libraries, * on which your project depends and, of course, the classes of current project. * -- 2.39.5