org.argeo.api.uuid/src/org/argeo/api/uuid/UuidIdentified.java

   1 package org.argeo.api.uuid;
   2
   3 import java.util.UUID;
   4
   5 /**
   6  * An object identified by a {@link UUID}. Typically used to fasten indexing and
   7  * comparisons of objects or records. THe method to implement is {@link #uuid()}
   8  * so that any record with an <code>uuid</code> field can easily be enriched
   9  * with this interface.
  10  */
  11 public interface UuidIdentified {
  12         /** The UUID identifier. */
  13         UUID uuid();
  14
  15         /** The UUID identifier, for compatibility with beans accessors. */
  16         default UUID getUuid() {
  17                 return uuid();
  18         }
  19
  20         /**
  21          * Helper to implement the equals method of an {@link UuidIdentified}.<br/>
  22          *
  23          * <pre>
  24          * &#64;Override
  25          * public boolean equals(Object o) {
  26          *      return UuidIdentified.equals(this, o);
  27          * }
  28          * </pre>
  29          */
  30         static boolean equals(UuidIdentified uuidIdentified, Object o) {
  31                 assert uuidIdentified != null;
  32                 if (o == null)
  33                         return false;
  34                 if (uuidIdentified == o)
  35                         return true;
  36                 if (o instanceof UuidIdentified u)
  37                         return uuidIdentified.uuid().equals(u.uuid());
  38                 else
  39                         return false;
  40         }
  41
  42         /**
  43          * Helper to implement the hash code method of an {@link UuidIdentified}.<br/>
  44          *
  45          * <pre>
  46          * &#64;Override
  47          * public int hashCode() {
  48          *      return UuidIdentified.hashCode(this);
  49          * }
  50          * </pre>
  51          */
  52         static int hashCode(UuidIdentified uuidIdentified) {
  53                 assert uuidIdentified != null;
  54                 return uuidIdentified.getUuid().hashCode();
  55         }
  56
  57 }