opendaylight/netconf/netconf-mapping-api/src/main/java/org/opendaylight/controller/netconf/mapping/api/HandlingPriority.java

   1 /*
   2  * Copyright (c) 2013 Cisco Systems, Inc. and others.  All rights reserved.
   3  *
   4  * This program and the accompanying materials are made available under the
   5  * terms of the Eclipse Public License v1.0 which accompanies this distribution,
   6  * and is available at http://www.eclipse.org/legal/epl-v10.html
   7  */
   8
   9 package org.opendaylight.controller.netconf.mapping.api;
  10
  11 import com.google.common.base.Optional;
  12 import com.google.common.base.Preconditions;
  13
  14 public class HandlingPriority implements Comparable<HandlingPriority> {
  15
  16     public static final HandlingPriority CANNOT_HANDLE = new HandlingPriority();
  17     public static final HandlingPriority HANDLE_WITH_DEFAULT_PRIORITY = new HandlingPriority(Integer.MIN_VALUE);
  18     public static final HandlingPriority HANDLE_WITH_MAX_PRIORITY = new HandlingPriority(Integer.MAX_VALUE);
  19
  20     private Integer priority;
  21
  22     public static HandlingPriority getHandlingPriority(int priority) {
  23         return new HandlingPriority(priority);
  24     }
  25
  26     private HandlingPriority(int priority) {
  27         this.priority = priority;
  28     }
  29
  30     private HandlingPriority() {
  31     }
  32
  33     /**
  34      * @return priority number or Optional.absent otherwise
  35      */
  36     public Optional<Integer> getPriority() {
  37         return Optional.fromNullable(priority);
  38     }
  39
  40     public HandlingPriority increasePriority(int priorityIncrease) {
  41         Preconditions.checkState(priority!=null, "Unable to increase priority for %s", this);
  42         Preconditions.checkArgument(priorityIncrease > 0, "Negative increase");
  43         Preconditions.checkArgument(Long.valueOf(priority) + priorityIncrease < Integer.MAX_VALUE,
  44                 "Resulting priority cannot be higher than %s", Integer.MAX_VALUE);
  45         return getHandlingPriority(priority + priorityIncrease);
  46     }
  47
  48     @Override
  49     public int compareTo(HandlingPriority o) {
  50         if (this == o)
  51             return 0;
  52         if (this == CANNOT_HANDLE)
  53             return -1;
  54         if (o == CANNOT_HANDLE)
  55             return 1;
  56
  57         if (priority > o.priority)
  58             return 1;
  59         if (priority == o.priority)
  60             return 0;
  61         if (priority < o.priority)
  62             return -1;
  63
  64         throw new IllegalStateException("Unexpected state");
  65     }
  66
  67     @Override
  68     public boolean equals(Object o) {
  69         if (this == o)
  70             return true;
  71         if (!(o instanceof HandlingPriority))
  72             return false;
  73
  74         HandlingPriority that = (HandlingPriority) o;
  75
  76         if (priority != null ? !priority.equals(that.priority) : that.priority != null)
  77             return false;
  78
  79         return true;
  80     }
  81
  82     @Override
  83     public int hashCode() {
  84         return priority != null ? priority.hashCode() : 0;
  85     }
  86 }