org.pepsoft.util.plugins

Class PluginManager

java.lang.Object

org.pepsoft.util.plugins.PluginManager

public final class PluginManager
extends Object

A general purpose plugin manager.

Method Summary

Modifier and Type	Method and Description
static <T> List<T>	findPlugins(Class<T> type, String descriptorPath, ClassLoader classLoader) Obtain a list of instances of all plugins available through a particular classloader, or from plugin jars discovered by a previous invocation of loadPlugins(File, PublicKey, String, Version, boolean), which implement a particular type.
static @NotNull List<String>	getErrors() Get the list of errors, if any, that occurred while loading the plugins.
static @NotNull List<String>	getMessages() Get the list of informational messages, if any, that were generated while loading the plugins.
static ClassLoader	getPluginClassLoader() Get a classloader which gives access to the classes of all the plugins.
static Descriptor	loadDescriptor(InputStream in, String name) Load a plugin descriptor from an input stream.
static void	loadPlugins(File pluginDir, PublicKey publicKey, String descriptorPath, Version hostVersion, boolean updatePlugins) Load plugin jars from a directory, which are signed with a particular private key.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

loadPlugins

public static void loadPlugins(File pluginDir,
                               PublicKey publicKey,
                               String descriptorPath,
                               Version hostVersion,
                               boolean updatePlugins)

Load plugin jars from a directory, which are signed with a particular private key. Optionally check for updates and replace versions which have updates with their newer versions.

This method should be invoked only once. Any discovered and properly signed plugin jars will be available to be returned by later invocations of the findPlugins(Class, String, ClassLoader) method.

Parameters:

pluginDir - The directory from which to load the plugins.

publicKey - The public key corresponding to the private key with which the plugins must have been signed.

descriptorPath - The resource path of the file containing the plugin descriptor.

hostVersion - The version of the host, for the update checking process and for checking the minimum required host version of the plugins.

findPlugins

public static <T> List<T> findPlugins(Class<T> type,
                                      String descriptorPath,
                                      ClassLoader classLoader)

Obtain a list of instances of all plugins available through a particular classloader, or from plugin jars discovered by a previous invocation of loadPlugins(File, PublicKey, String, Version, boolean), which implement a particular type.

Type Parameters:

T - The type of plugin to return.

Parameters:

type - The type of plugin to return.

descriptorPath - The resource path of the file containing the plugin descriptor.

classLoader - The classloader from which to discover plugins.

Returns:

A list of newly instantiated plugin objects of the specified type available from the specified classloader and/or any earlier discovered plugin jars.

getPluginClassLoader

public static ClassLoader getPluginClassLoader()

Get a classloader which gives access to the classes of all the plugins.

Returns:

A classloader which gives access to the classes of all the plugins.

getMessages

@NotNull
public static @NotNull List<String> getMessages()

Get the list of informational messages, if any, that were generated while loading the plugins.

Returns:

The list of informational messages, if any, that were generated while loading the plugins. May be empty, but is never null.

getErrors

@NotNull
public static @NotNull List<String> getErrors()

Get the list of errors, if any, that occurred while loading the plugins.

Returns:

The list of errors, if any, that occurred while loading the plugins. May be empty, but is never null.

loadDescriptor

public static Descriptor loadDescriptor(InputStream in,
                                        String name)
                                 throws IOException

Load a plugin descriptor from an input stream. Both the old format and the new JSON-based format are supported.

Parameters:

in - The input stream from which to read the descriptor. Will be closed.

name - A name associated with the input stream, to be used as a fall back plugin name. May be null if not available.

Returns:

The plugin descriptor read from the stream.

Throws:

IOException