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diff --git a/velocity-engine-core/src/main/java/org/apache/velocity/util/introspection/TypeConversionHandler.java b/velocity-engine-core/src/main/java/org/apache/velocity/util/introspection/TypeConversionHandler.java
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@@ -0,0 +1,68 @@
+package org.apache.velocity.util.introspection;
+
+/*
+ * 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.
+ */
+
+import java.lang.reflect.Type;
+
+/**
+ * A conversion handler adds admissible conversions between Java types whenever Velocity introspection has to map
+ * VTL methods and property accessors to Java methods.
+ * Both methods must be consistent: <code>getNeededConverter</code> must not return <code>null</code> whenever
+ * <code>isExplicitlyConvertible</code> returned true with the same arguments.
+ *
+ * @author <a href="mailto:claude.brisson@gmail.com">Claude Brisson</a>
+ * @version $Id: ConversionHandler.java $
+ * @since 2.1
+ */
+
+public interface TypeConversionHandler
+{
+    /**
+     * Check to see if the conversion can be done using an explicit conversion
+     * @param formal expected formal type
+     * @param actual provided argument type
+     * @param possibleVarArg whether var arg is possible
+     * @return null if no conversion is needed, or the appropriate Converter object
+     * @since 2.1
+     */
+    boolean isExplicitlyConvertible(Type formal, Class<?> actual, boolean possibleVarArg);
+
+    /**
+     * Returns the appropriate Converter object needed for an explicit conversion
+     * Returns null if no conversion is needed.
+     *
+     * @param formal expected formal type
+     * @param actual provided argument type
+     * @return null if no conversion is needed, or the appropriate Converter object
+     * @since 2.1
+     */
+    Converter<?> getNeededConverter(Type formal, Class<?> actual);
+
+    /**
+     * Add the given converter to the handler. Implementation should be thread-safe.
+     *
+     * @param formal expected formal type
+     * @param actual provided argument type
+     * @param converter converter
+     * @since 2.1
+     */
+    void addConverter(Type formal, Class<?> actual, Converter<?> converter);
+
+}