static {
   ourValidRevisions.put(HEAD.getName(), HEAD);
   ourValidRevisions.put(WORKING.getName(), WORKING);
   ourValidRevisions.put(PREVIOUS.getName(), PREVIOUS);
   ourValidRevisions.put(BASE.getName(), BASE);
   ourValidRevisions.put(COMMITTED.getName(), COMMITTED);
 }
 /**
  * Compares this object with another <b>SVNRevision</b> object.
  *
  * @param o an object to be compared with; if it's not an <b>SVNRevision</b> then this method
  *     certainly returns <span class="javakeyword">false</span>
  * @return <span class="javakeyword">true</span> if equal, otherwise <span
  *     class="javakeyword">false</span>
  */
 public boolean equals(Object o) {
   if (o == null || o.getClass() != SVNRevision.class) {
     return false;
   }
   SVNRevision r = (SVNRevision) o;
   if (myRevision >= 0) {
     return myRevision == r.getNumber();
   } else if (myDate != null) {
     return myDate.equals(r.getDate());
   } else if (myName != null) {
     return myName.equals(r.getName());
   }
   return !r.isValid();
 }