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diff --git a/spss/server/serverlib/src/main/java/at/gv/egovernment/moa/spss/server/transaction/TransactionIDGenerator.java b/spss/server/serverlib/src/main/java/at/gv/egovernment/moa/spss/server/transaction/TransactionIDGenerator.java
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+++ b/spss/server/serverlib/src/main/java/at/gv/egovernment/moa/spss/server/transaction/TransactionIDGenerator.java
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+/*
+ * Copyright 2003 Federal Chancellery Austria
+ * MOA-SPSS has been developed in a cooperation between BRZ, the Federal
+ * Chancellery Austria - ICT staff unit, and Graz University of Technology.
+ *
+ * Licensed under the EUPL, Version 1.1 or - as soon they will be approved by
+ * the European Commission - subsequent versions of the EUPL (the "Licence");
+ * You may not use this work except in compliance with the Licence.
+ * You may obtain a copy of the Licence at:
+ * http://www.osor.eu/eupl/
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the Licence is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the Licence for the specific language governing permissions and
+ * limitations under the Licence.
+ *
+ * This product combines work with different licenses. See the "NOTICE" text
+ * file for details on the various modules and licenses.
+ * The "NOTICE" text file is part of the distribution. Any derivative works
+ * that you distribute must include a readable copy of the "NOTICE" text file.
+ */
+
+
+package at.gv.egovernment.moa.spss.server.transaction;
+
+
+/**
+ * A generator for unique transaction IDs.
+ * 
+ * <p>The transaction IDs are of the form "<base>-<counter>", where:
+ * <ul> 
+ * <li><code>base</code> is initialized with the system time when this class is
+ * being loaded</li>
+ * <li><code>counter</code> is incremented sequentially on each call to
+ * <code>nextID()</code></li>
+ * </ul>
+ * </p>
+ * 
+ * <p> Assuming that it is highly unlikely that MOA servers are started at
+ * exactly the same time instant, the mechanism provided by this class should
+ * guarantee unique transaction IDs across multiple restarts and/or instances of
+ * the server.</p>
+ * 
+ * @author Patrick Peck
+ * @author Stefan Knirsch
+ */
+public class TransactionIDGenerator {
+
+  /** Request sequence number. */
+  private static long counter = 0;
+  /** The base value to which to append the sequence number. */
+  private static String base = null;
+
+  /**
+   * Set up the initial base value.
+   */
+  static {
+    synchronized (TransactionIDGenerator.class) {
+      base = Long.toString(System.currentTimeMillis());
+    }
+  }
+
+  /**
+   * Returns the next transaction ID.
+   * 
+   * @return The next transaction ID.
+   */
+  public static synchronized String nextID() {
+    counter++;
+
+    return (base + "-" + counter);
+  }
+
+}