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diff --git a/framework/src/ant/apache-ant-1.9.6/src/main/org/apache/tools/ant/types/selectors/modifiedselector/HashvalueAlgorithm.java b/framework/src/ant/apache-ant-1.9.6/src/main/org/apache/tools/ant/types/selectors/modifiedselector/HashvalueAlgorithm.java
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+++ b/framework/src/ant/apache-ant-1.9.6/src/main/org/apache/tools/ant/types/selectors/modifiedselector/HashvalueAlgorithm.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.tools.ant.types.selectors.modifiedselector;
+
+import java.io.File;
+import java.io.FileReader;
+import java.io.Reader;
+
+import org.apache.tools.ant.util.FileUtils;
+
+/**
+ * Computes a 'hashvalue' for the content of file using String.hashValue().
+ * Use of this algorithm doesn't require any additional nested <param>s and
+ * doesn't support any.
+ *
+ * @version 2003-09-13
+ * @since  Ant 1.6
+ */
+public class HashvalueAlgorithm implements Algorithm {
+
+    /**
+     * This algorithm doesn't need any configuration.
+     * Therefore it's always valid.
+     * @return always true
+     */
+    public boolean isValid() {
+        return true;
+    }
+
+    /**
+     * Computes a 'hashvalue' for a file content.
+     * It reads the content of a file, convert that to String and use the
+     * String.hashCode() method.
+     * @param file  The file for which the value should be computed
+     * @return the hashvalue or <i>null</i> if the file couldn't be read
+     */
+     // Because the content is only read the file will not be damaged. I tested
+     // with JPG, ZIP and PDF as binary files.
+    public String getValue(File file) {
+        Reader r = null;
+        try {
+            if (!file.canRead()) {
+                return null;
+            }
+            r = new FileReader(file);
+            int hash = FileUtils.readFully(r).hashCode();
+            return Integer.toString(hash);
+        } catch (Exception e) {
+            return null;
+        } finally {
+            FileUtils.close(r);
+        }
+    }
+
+
+    /**
+     * Override Object.toString().
+     * @return information about this comparator
+     */
+    public String toString() {
+        return "HashvalueAlgorithm";
+    }
+
+}