1 files changed, 52 insertions, 0 deletions
diff --git a/src/main/java/org/apache/commons/math3/util/IterationListener.java b/src/main/java/org/apache/commons/math3/util/IterationListener.java
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+++ b/src/main/java/org/apache/commons/math3/util/IterationListener.java
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+/*
+ * 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.commons.math3.util;
+
+import java.util.EventListener;
+
+/** The listener interface for receiving events occurring in an iterative algorithm. */
+public interface IterationListener extends EventListener {
+    /**
+     * Invoked after completion of the initial phase of the iterative algorithm (prior to the main
+     * iteration loop).
+     *
+     * @param e The {@link IterationEvent} object.
+     */
+    void initializationPerformed(IterationEvent e);
+
+    /**
+     * Invoked each time an iteration is completed (in the main iteration loop).
+     *
+     * @param e The {@link IterationEvent} object.
+     */
+    void iterationPerformed(IterationEvent e);
+
+    /**
+     * Invoked each time a new iteration is completed (in the main iteration loop).
+     *
+     * @param e The {@link IterationEvent} object.
+     */
+    void iterationStarted(IterationEvent e);
+
+    /**
+     * Invoked after completion of the operations which occur after breaking out of the main
+     * iteration loop.
+     *
+     * @param e The {@link IterationEvent} object.
+     */
+    void terminationPerformed(IterationEvent e);
+}