geode-core/src/main/java/org/apache/geode/internal/sequencelog/SequenceLogger.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more contributor license
 * agreements. See the NOTICE file distributed with this work for additional information regarding
 * copyright ownership. The ASF licenses this file to You 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.apache.geode.internal.sequencelog;

/**
 * A logger that allows the user to "log" events in a sequence diagram. Useful for tracking the
 * movement of an object through our distributed system, for example.
 *
 */
public interface SequenceLogger {
  /**
   * A transition in the sequence diagram. We will actually be recording the toString value of all
   * of these fields if logging is enabled for this graph type.
   *
   * There can be many independent sequence diagrams that are logged. Each sequence diagram is
   * identified by a graphName and a graphType.
   *
   * Each log statement creates a transition in the diagram
   *
   * <pre>
   * Source         Dest
   *   |             |
   *   |-(edgeName)->| (now in state "state")
   * </pre>
   *
   * The graphName can a Pattern, at which point it will be considered a transition for all
   * graphNames that match the pattern at that time to the given state.
   *
   * @param type the type of graph this is.
   * @param graphName The name of the graph we're recording. For example, an individual key, like
   *        "Object_123"
   * @param edgeName the name of the edge. For example ("put", or "GII")
   * @param state the final state of the destination. For example ("value_123", or "created").
   * @param source the source, for example ("member 1, region 1");
   * @param dest the destination, for example ("member 2, region 1");
   */
  void logTransition(GraphType type, Object graphName, Object edgeName, Object state, Object source,
      Object dest);

  boolean isEnabled(GraphType type);

  void flush() throws InterruptedException;
}