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.Objects;
  12 import com.google.common.base.Optional;
  13 import com.google.common.base.Preconditions;
  14
  15 public final class HandlingPriority implements Comparable<HandlingPriority> {
  16
  17     public static final HandlingPriority CANNOT_HANDLE = new HandlingPriority();
  18     public static final HandlingPriority HANDLE_WITH_DEFAULT_PRIORITY = new HandlingPriority(Integer.MIN_VALUE);
  19     public static final HandlingPriority HANDLE_WITH_MAX_PRIORITY = new HandlingPriority(Integer.MAX_VALUE);
  20
  21     private Integer priority;
  22
  23     public static HandlingPriority getHandlingPriority(int priority) {
  24         return new HandlingPriority(priority);
  25     }
  26
  27     private HandlingPriority(int priority) {
  28         this.priority = priority;
  29     }
  30
  31     private HandlingPriority() {
  32     }
  33
  34     /**
  35      * @return priority number or Optional.absent otherwise
  36      */
  37     public Optional<Integer> getPriority() {
  38         return Optional.fromNullable(priority);
  39     }
  40
  41     public HandlingPriority increasePriority(int priorityIncrease) {
  42         Preconditions.checkState(priority!=null, "Unable to increase priority for %s", this);
  43         Preconditions.checkArgument(priorityIncrease > 0, "Negative increase");
  44         Preconditions.checkArgument(Long.valueOf(priority) + priorityIncrease < Integer.MAX_VALUE,
  45                 "Resulting priority cannot be higher than %s", Integer.MAX_VALUE);
  46         return getHandlingPriority(priority + priorityIncrease);
  47     }
  48
  49     public boolean isCannotHandle() {
  50         return this.equals(CANNOT_HANDLE);
  51     }
  52
  53     @Override
  54     public int compareTo(HandlingPriority o) {
  55         if (this == o) {
  56             return 0;
  57         }
  58         if (isCannotHandle()) {
  59             return -1;
  60         }
  61         if (o.isCannotHandle()) {
  62             return 1;
  63         }
  64
  65         if (priority > o.priority){
  66             return 1;
  67         }
  68         if (priority.equals(o.priority)){
  69             return 0;
  70         }
  71         if (priority < o.priority){
  72             return -1;
  73         }
  74
  75         throw new IllegalStateException("Unexpected state comparing " + this + " with " + o);
  76     }
  77
  78     @Override
  79     public boolean equals(Object o) {
  80         if (this == o){
  81             return true;
  82         }
  83         if (!(o instanceof HandlingPriority)){
  84             return false;
  85         }
  86
  87         HandlingPriority that = (HandlingPriority) o;
  88
  89         if (priority != null ? !priority.equals(that.priority) : that.priority != null){
  90             return false;
  91         }
  92
  93         return true;
  94     }
  95
  96     @Override
  97     public int hashCode() {
  98         return priority != null ? priority.hashCode() : 0;
  99     }
 100
 101     @Override
 102     public String toString() {
 103         return Objects.toStringHelper(this)
 104                 .add("priority", priority)
 105                 .toString();
 106     }
 107 }