uniqueid.java

Java写的TDS协议(JDBC/ODBC)实现

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package net.sourceforge.jtds.jdbc;

/**
 * return a monotonically increasing number.
 *
 * This class provides a thread safe way of generating unique
 * numbers.  It is used in the TDS driver to help generate unique
 * names for temporary stored procedures and temporary tables.
 *
 * @author Craig Spannring
 * @version  $Id: UniqueId.java,v 1.1 2002/10/14 10:48:59 alin_sinpalean Exp $
 */
public class UniqueId {
   public static final String cvsVersion = "$Id: UniqueId.java,v 1.1 2002/10/14 10:48:59 alin_sinpalean Exp $";

   // next number to return from the getUniqueId() method
   private static long  id = 1;

   /**
    * return a unique number.
    * <p>
    * The number is unique for a given invocation of the JVM.  Currently
    * the number is monotonically increasing, but I make no guarantees
    * that it will be that way in future releases.
    *
    * @return unique number
    */
   public static synchronized long getUniqueId()
   {
      return id++;
   }
}