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diff --git a/src/main/java/org/apache/commons/lang3/exception/ExceptionContext.java b/src/main/java/org/apache/commons/lang3/exception/ExceptionContext.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.lang3.exception;
+
+import java.util.List;
+import java.util.Set;
+
+import org.apache.commons.lang3.tuple.Pair;
+
+/**
+ * Allows the storage and retrieval of contextual information based on label-value
+ * pairs for exceptions.
+ * <p>
+ * Implementations are expected to manage the pairs in a list-style collection
+ * that keeps the pairs in the sequence of their addition.
+ * </p>
+ *
+ * @see ContextedException
+ * @see ContextedRuntimeException
+ * @since 3.0
+ */
+public interface ExceptionContext {
+
+    /**
+     * Adds a contextual label-value pair into this context.
+     * <p>
+     * The pair will be added to the context, independently of an already
+     * existing pair with the same label.
+     * </p>
+     *
+     * @param label  the label of the item to add, {@code null} not recommended
+     * @param value  the value of item to add, may be {@code null}
+     * @return {@code this}, for method chaining, not {@code null}
+     */
+    ExceptionContext addContextValue(String label, Object value);
+
+    /**
+     * Retrieves the full list of label-value pairs defined in the contextual data.
+     *
+     * @return the list of pairs, not {@code null}
+     */
+    List<Pair<String, Object>> getContextEntries();
+
+    /**
+     * Retrieves the full set of labels defined in the contextual data.
+     *
+     * @return the set of labels, not {@code null}
+     */
+    Set<String> getContextLabels();
+
+    /**
+     * Retrieves all the contextual data values associated with the label.
+     *
+     * @param label  the label to get the contextual values for, may be {@code null}
+     * @return the contextual values associated with the label, never {@code null}
+     */
+    List<Object> getContextValues(String label);
+
+    /**
+     * Retrieves the first available contextual data value associated with the label.
+     *
+     * @param label  the label to get the contextual value for, may be {@code null}
+     * @return the first contextual value associated with the label, may be {@code null}
+     */
+    Object getFirstContextValue(String label);
+
+    /**
+     * Gets the contextualized error message based on a base message.
+     * This will add the context label-value pairs to the message.
+     *
+     * @param baseMessage  the base exception message <b>without</b> context information appended
+     * @return the exception message <b>with</b> context information appended, not {@code null}
+     */
+    String getFormattedExceptionMessage(String baseMessage);
+
+    /**
+     * Sets a contextual label-value pair into this context.
+     * <p>
+     * The pair will be added normally, but any existing label-value pair with
+     * the same label is removed from the context.
+     * </p>
+     *
+     * @param label  the label of the item to add, {@code null} not recommended
+     * @param value  the value of item to add, may be {@code null}
+     * @return {@code this}, for method chaining, not {@code null}
+     */
+    ExceptionContext setContextValue(String label, Object value);
+
+}