Briefly, this error occurs when Elasticsearch is unable to locate the specified plugin class. This could be due to the plugin not being installed, the class name being misspelled, or the plugin not being properly loaded. To resolve this issue, you can try installing the plugin if it’s not already installed, double-check the class name for any spelling errors, or ensure the plugin is correctly loaded by restarting Elasticsearch.
This guide will help you check for common problems that cause the log ” Could not find plugin class [” + className + “] ” to appear. To understand the issues related to this log, read the explanation below about the following Elasticsearch concepts: plugin, plugins.
Log Context
Log “Could not find plugin class [” + className + “]” class name is PluginsService.java. We extracted the following from Elasticsearch source code for those seeking an in-depth context :
private static Class extends Plugin> loadPluginClass(String className; ClassLoader loader) { try { return Class.forName(className; false; loader).asSubclass(Plugin.class); } catch (ClassNotFoundException e) { throw new ElasticsearchException("Could not find plugin class [" + className + "]"; e); } } // package-private for testing static Plugin loadPlugin(Class extends Plugin> pluginClass; Settings settings; Path configPath) {