1 files changed, 85 insertions, 0 deletions
diff --git a/spss/server/serverlib/src/main/java/at/gv/egovernment/moa/spss/server/util/IdGenerator.java b/spss/server/serverlib/src/main/java/at/gv/egovernment/moa/spss/server/util/IdGenerator.java
new file mode 100644
index 000000000..a8d9e1b3a
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+++ b/spss/server/serverlib/src/main/java/at/gv/egovernment/moa/spss/server/util/IdGenerator.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.util;
+
+import java.util.Set;
+
+/**
+ * Generate unique ID values for various objects in the response.
+ * 
+ * @author Patrick Peck
+ * @version $Id$
+ */
+public class IdGenerator {
+  /** The base value to append the counter to. */
+  private String base;
+  /** The <code>Set</code> of reserved ID values. */
+  private Set reserved;
+  /** The sequence number. */
+  private int count;
+  
+  /**
+   * Create a new <code>IdGenerator</code>.
+   * 
+   * @param base A base value to append the IDs to. The creator of this object
+   * should provide a base value, so that appending the counter leads to unique
+   * IDs.
+   * @param reserved The <code>Set</code> of reserved IDs. A call to 
+   * <code>uniqueId()</code> will respect the reserved IDs.
+   */
+  public IdGenerator(String base, Set reserved) {
+    this.base = base;
+    this.reserved = reserved;
+    count = 1;
+  }
+  
+  /**
+   * Create the next ID value in the sequence.
+   * 
+   * @return The next ID value in the sequence.
+   */
+  protected String nextId() {
+    return base + "-" + count++;
+  }
+  
+  /**
+   * Create the next unique ID value which is unique in the reserved ID set.
+   * 
+   * The created ID is added to the set of reserved IDs.
+   * 
+   * @return The next ID value.
+   */
+  public String uniqueId() {
+    String nextId;
+
+    while (reserved.contains(nextId = nextId()));
+    
+    reserved.add(nextId);
+    
+    return nextId;
+        
+  }
+  
+}