1 files changed, 67 insertions, 0 deletions
diff --git a/src/de/lmu/ifi/dbs/elki/utilities/io/ByteBufferInputStream.java b/src/de/lmu/ifi/dbs/elki/utilities/io/ByteBufferInputStream.java
new file mode 100644
index 00000000..57cd352d
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+++ b/src/de/lmu/ifi/dbs/elki/utilities/io/ByteBufferInputStream.java
@@ -0,0 +1,67 @@
+package de.lmu.ifi.dbs.elki.utilities.io;
+
+/*
+ This file is part of ELKI:
+ Environment for Developing KDD-Applications Supported by Index-Structures
+
+ Copyright (C) 2014
+ Ludwig-Maximilians-Universität München
+ Lehr- und Forschungseinheit für Datenbanksysteme
+ ELKI Development Team
+
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU Affero General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU Affero General Public License for more details.
+
+ You should have received a copy of the GNU Affero General Public License
+ along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+import java.io.InputStream;
+import java.nio.ByteBuffer;
+
+/**
+ * Wrap an existing ByteBuffer as InputStream.
+ * 
+ * @author Erich Schubert
+ * 
+ * @apiviz.has ByteBuffer
+ */
+public class ByteBufferInputStream extends InputStream {
+  /**
+   * The actual buffer we're using.
+   */
+  final ByteBuffer buffer;
+
+  /**
+   * Constructor.
+   * 
+   * @param buffer ByteBuffer to wrap.
+   */
+  public ByteBufferInputStream(ByteBuffer buffer) {
+    super();
+    this.buffer = buffer;
+  }
+
+  @Override
+  public int read() {
+    if(buffer.hasRemaining()) {
+      return -1;
+    }
+    // Note: is this and 0xFF needed?
+    return (buffer.get() & 0xFF);
+  }
+
+  @Override
+  public int read(byte[] b, int off, int len) {
+    final int maxread = Math.min(len, buffer.remaining());
+    buffer.get(b, off, maxread);
+    return maxread == 0 ? -1 : maxread;
+  }
+}