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diff --git a/velocity-engine-core/src/main/java/org/apache/velocity/runtime/parser/CharStream.java b/velocity-engine-core/src/main/java/org/apache/velocity/runtime/parser/CharStream.java
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+++ b/velocity-engine-core/src/main/java/org/apache/velocity/runtime/parser/CharStream.java
@@ -0,0 +1,128 @@
+package org.apache.velocity.runtime.parser;
+
+/*
+ * 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.
+ */
+/* Generated By:JavaCC: Do not edit this line. CharStream.java Version 2.1 */
+
+/**
+ * This interface describes a character stream that maintains line and
+ * column number positions of the characters.  It also has the capability
+ * to backup the stream to some extent.  An implementation of this
+ * interface is used in the TokenManager implementation generated by
+ * JavaCCParser.
+ *
+ * All the methods except backup can be implemented in any fashion. backup
+ * needs to be implemented correctly for the correct operation of the lexer.
+ * Rest of the methods are all used to get information like line number,
+ * column number and the String that constitutes a token and are not used
+ * by the lexer. Hence their implementation won't affect the generated lexer's
+ * operation.
+ */
+
+public interface CharStream
+{
+    /**
+    * Returns the next character from the selected input.  The method
+    * of selecting the input is the responsibility of the class
+    * implementing this interface.  Can throw any java.io.IOException.
+    * @return read char
+    * @throws java.io.IOException
+    */
+    char readChar() throws java.io.IOException;
+
+    /**
+    * Returns the column number of the last character for current token (being
+    * matched after the last call to BeginTOken).
+    * @return ending column number
+    */
+    int getEndColumn();
+
+    /**
+    * Returns the line number of the last character for current token (being
+    * matched after the last call to BeginTOken).
+    * @return ending line number
+    */
+    int getEndLine();
+
+    /**
+    * Returns the column number of the first character for current token (being
+    * matched after the last call to BeginTOken).
+    * @return starting column number
+    */
+    int getBeginColumn();
+
+    /**
+    * Returns the line number of the first character for current token (being
+    * matched after the last call to BeginTOken).
+    * @return starting line number
+    */
+    int getBeginLine();
+
+    /**
+    * Backs up the input stream by amount steps. Lexer calls this method if it
+    * had already read some characters, but could not use them to match a
+    * (longer) token. So, they will be used again as the prefix of the next
+    * token and it is the implemetation's responsibility to do this right.
+    * @param amount
+    */
+    void backup(int amount);
+
+    /**
+    * Returns the next character that marks the beginning of the next token.
+    * All characters must remain in the buffer between two successive calls
+    * to this method to implement backup correctly.
+    * @return next token start char
+    * @throws java.io.IOException
+    */
+    char BeginToken() throws java.io.IOException;
+
+    /**
+    * Returns a string made up of characters from the marked token beginning
+    * to the current buffer position. Implementations have the choice of returning
+    * anything that they want to. For example, for efficiency, one might decide
+    * to just return null, which is a valid implementation.
+    * @return token image
+    */
+    String GetImage();
+
+    /**
+    * <p>Returns an array of characters that make up the suffix of length 'len' for
+    * the currently matched token. This is used to build up the matched string
+    * for use in actions in the case of MORE. A simple and inefficient
+    * implementation of this is as follows :</p>
+    * <pre><code>
+    *   {
+    *      String t = GetImage();
+    *      return t.substring(t.length() - len, t.length()).toCharArray();
+    *   }
+    *   </code></pre>
+    *   @param len suffix len
+    *   @return suffix
+    */
+    char[] GetSuffix(int len);
+
+    /**
+    * The lexer calls this function to indicate that it is done with the stream
+    * and hence implementations can free any resources held by this class.
+    * Again, the body of this function can be just empty and it will not
+    * affect the lexer's operation.
+    */
+    void Done();
+
+}