CompoundPluginDescriptorFinder implements PluginDescriptorFinder { public CompoundPluginDescriptorFinder add(PluginDescriptorFinder finder) { if (finder == null) { throw new IllegalArgumentException("null not allowed"); } finders.add(finder); return this; }  CompoundPluginDescriptorFinder add(PluginDescriptorFinder finder); int size(); @Override boolean isApplicable(Path pluginPath); @Override PluginDescriptor find(Path pluginPath);  }
@Test public void add() { CompoundPluginDescriptorFinder descriptorFinder = new CompoundPluginDescriptorFinder(); assertEquals(0, descriptorFinder.size()); descriptorFinder.add(new PropertiesPluginDescriptorFinder()); assertEquals(1, descriptorFinder.size()); }