public static PipePluginClassLoaderManager getInstance() {
    return instance;
  }
Each {@link PipePlugin} is equipped with a dedicated {@link PipePluginClassLoader}. When a
{@link PipePlugin} is created, the corresponding {@link PipePluginClassLoader} is generated and
used to load the {@link PipePlugin}. When the {@link PipePlugin} is deleted, its associated
{@link PipePluginClassLoader} is also removed. The lifecycle of the {@link
PipePluginClassLoader} is strictly consistent with the lifecycle of the {@link PipePlugin} it
serves.
iotdb-core/node-commons/src/main/java/org/apache/iotdb/commons/pipe/agent/plugin/service/PipePluginClassLoaderManager.java