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diff --git a/src/java/org/apache/fop/util/SubInputStream.java b/src/java/org/apache/fop/util/SubInputStream.java
new file mode 100644
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--- /dev/null
+++ b/src/java/org/apache/fop/util/SubInputStream.java
@@ -0,0 +1,92 @@
+/*
+ * Copyright 2005 The Apache Software Foundation.
+ *
+ * Licensed 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.
+ */
+
+/* $Id$ */
+
+package org.apache.fop.util;
+
+import java.io.FilterInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+
+/**
+ * This class is a FilterInputStream descendant that reads from an underlying InputStream
+ * up to a defined number of bytes or the end of the underlying stream. Closing this InputStream
+ * will not result in the underlying InputStream to be closed, too.
+ * <p>
+ * This InputStream can be used to read chunks from a larger file of which the length is
+ * known in advance.
+ */
+public class SubInputStream extends FilterInputStream {
+
+    /** Indicates the number of bytes remaning to be read from the underlying InputStream. */
+    private long bytesToRead;
+    
+    /**
+     * Creates a new SubInputStream.
+     * @param in the InputStream to read from
+     * @param maxLen the maximum number of bytes to read from the underlying InputStream until
+     *               the end-of-file is signalled.
+     */
+    public SubInputStream(InputStream in, long maxLen) {
+        super(in);
+        this.bytesToRead = maxLen;
+    }
+
+    /** @see java.io.InputStream#read() */
+    public int read() throws IOException {
+        if (bytesToRead > 0) {
+            int result = super.read();
+            if (result <= 0) {
+                bytesToRead--;
+                return result;
+            } else {
+                return -1;
+            }
+        } else {
+            return -1;
+        }
+    }
+    
+    /** @see java.io.InputStream#read(byte[], int, int) */
+    public int read(byte[] b, int off, int len) throws IOException {
+        if (bytesToRead == 0) {
+            return -1;
+        }
+        int effRead = (int)Math.min(bytesToRead, len);
+        //cast to int is safe because len can never be bigger than Integer.MAX_VALUE
+        
+        int result = super.read(b, off, effRead);
+        if (result >= 0) {
+            bytesToRead -= result;
+        }
+        return result;
+    }
+    
+    /** @see java.io.InputStream#skip(long) */
+    public long skip(long n) throws IOException {
+        long effRead = Math.min(bytesToRead, n);
+        long result = super.skip(effRead);
+        bytesToRead -= result;
+        return result;
+    }
+
+    /** @see java.io.InputStream#close() */
+    public void close() throws IOException {
+        //Don't close the underlying InputStream!!!
+        this.bytesToRead = 0;
+    }
+}