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diff --git a/src/main/java/org/apache/commons/math3/optimization/ConvergenceChecker.java b/src/main/java/org/apache/commons/math3/optimization/ConvergenceChecker.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.optimization;
+
+/**
+ * This interface specifies how to check if an optimization algorithm has converged. <br>
+ * Deciding if convergence has been reached is a problem-dependent issue. The user should provide a
+ * class implementing this interface to allow the optimization algorithm to stop its search
+ * according to the problem at hand. <br>
+ * For convenience, three implementations that fit simple needs are already provided: {@link
+ * SimpleValueChecker}, {@link SimpleVectorValueChecker} and {@link SimplePointChecker}. The first
+ * two consider that convergence is reached when the objective function value does not change much
+ * anymore, it does not use the point set at all. The third one considers that convergence is
+ * reached when the input point set does not change much anymore, it does not use objective function
+ * value at all.
+ *
+ * @param <PAIR> Type of the (point, objective value) pair.
+ * @see org.apache.commons.math3.optimization.SimplePointChecker
+ * @see org.apache.commons.math3.optimization.SimpleValueChecker
+ * @see org.apache.commons.math3.optimization.SimpleVectorValueChecker
+ * @deprecated As of 3.1 (to be removed in 4.0).
+ * @since 3.0
+ */
+@Deprecated
+public interface ConvergenceChecker<PAIR> {
+    /**
+     * Check if the optimization algorithm has converged.
+     *
+     * @param iteration Current iteration.
+     * @param previous Best point in the previous iteration.
+     * @param current Best point in the current iteration.
+     * @return {@code true} if the algorithm is considered to have converged.
+     */
+    boolean converged(int iteration, PAIR previous, PAIR current);
+}