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diff --git a/src/de/lmu/ifi/dbs/elki/utilities/io/LineReader.java b/src/de/lmu/ifi/dbs/elki/utilities/io/LineReader.java
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+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.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.io.Reader;
+
+/**
+ * Fast class to read a file, line per line.
+ * 
+ * Lines must be split using Unix newlines <code>\n</code>, linefeeds
+ * <code>\r</code> are ignored.
+ * 
+ * This is a rather minimal implementation, which supposedly pays off in
+ * performance. In particular, this class allows recycling the buffer, which
+ * will yield less object allocations and thus less garbage collection.
+ * 
+ * Usage example:
+ * 
+ * <pre>
+ * StringBuilder buf = new StringBuilder();
+ * LineReader reader = new LineReader(inputStream);
+ * // Clear buffer, and append next line.
+ * while(reader.readLine(buf.delete(0, buf.length()))) {
+ *   // process string in buffer.
+ * }
+ * </pre>
+ * 
+ * @author Erich Schubert
+ */
+public class LineReader implements AutoCloseable {
+  /** Buffer size to use */
+  final static int BUFFER_SIZE = 4096;
+
+  /** Input stream to read from */
+  Reader in;
+
+  /** Character buffer */
+  char[] buffer = new char[BUFFER_SIZE];
+
+  /** Current position, and length of buffer */
+  int pos = 0, end = 0;
+
+  /**
+   * Constructor
+   * 
+   * @param in Stream
+   */
+  public LineReader(InputStream in) {
+    this(new InputStreamReader(in));
+  }
+
+  /**
+   * Constructor
+   * 
+   * @param in Reader
+   */
+  public LineReader(Reader in) {
+    this.in = in;
+  }
+
+  /**
+   * Read a line into the given buffer.
+   * 
+   * @param buf Buffer.
+   * @return {@code true} if some characters have been read.
+   */
+  public boolean readLine(Appendable buf) throws IOException {
+    boolean success = false;
+    while(true) {
+      // Process buffer:
+      while(pos < end) {
+        success = true;
+        final char c = buffer[pos++];
+        if(c == '\n') {
+          return success;
+        }
+        if(c == '\r') {
+          continue;
+        }
+        buf.append(c);
+      }
+      // Refill buffer:
+      assert (pos >= end) : "Buffer wasn't empty when refilling!";
+      end = in.read(buffer, 0, buffer.length);
+      pos = 0;
+      if(end < 0) { // End of stream.
+        return success;
+      }
+    }
+  }
+
+  @Override
+  public void close() throws IOException {
+    if(in != null) {
+      in.close();
+    }
+  }
+}