https://github.com/Terracotta-OSS/statistics: A statistics framework used inside Ehcache and the Terracotta products 
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 * All content copyright Terracotta, Inc., unless otherwise indicated.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.terracotta.context;


The context graph mutation listener interface.

/**
 * The context graph mutation listener interface.
 */
public interface ContextListener {

  
Called when a new subgraph is attached.

 The parent node is the currently attached node to which the incoming graph has been attached. The added node is the newly attached sub-graph. The graph accessible beneath added may include sub-graphs that are already attached to this tree. 
Params:
  • parent – parent of the new sub-graph
  • added –  newly added sub-graph
/**
   * Called when a new subgraph is attached.
   * <p>
   * The {@code parent} node is the currently attached node to which the
   * incoming graph has been attached.  The {@code added} node is the newly
   * attached sub-graph.  The graph accessible beneath {@code added} may include
   * sub-graphs that are already attached to this tree.
   *
   * @param parent parent of the new sub-graph
   * @param added  newly added sub-graph
   */
  void graphAdded(TreeNode parent, TreeNode added);

  
Called when a subgraph is detached.

 The parent node the still attached node from which the outgoing graph has been detached. The removed node is the just detached sub-graph. The graph accessible beneath removed may include sub-graphs that are still attached to this tree. 
Params:
  • parent –  previous parent of the removed sub-graph
  • removed – the removed sub-graph
/**
   * Called when a subgraph is detached.
   * <p>
   * The {@code parent} node the still attached node from which the outgoing
   * graph has been detached.  The {@code removed} node is the just detached
   * sub-graph.  The graph accessible beneath {@code removed} may include
   * sub-graphs that are still attached to this tree.
   *
   * @param parent  previous parent of the removed sub-graph
   * @param removed the removed sub-graph
   */
  void graphRemoved(TreeNode parent, TreeNode removed);
}