Simon Hunt | 22c35df | 2017-04-26 17:28:42 -0700 | [diff] [blame] | 1 | /* |
Brian O'Connor | a09fe5b | 2017-08-03 21:12:30 -0700 | [diff] [blame] | 2 | * Copyright 2017-present Open Networking Foundation |
Simon Hunt | 22c35df | 2017-04-26 17:28:42 -0700 | [diff] [blame] | 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | * |
| 16 | */ |
| 17 | |
| 18 | package org.onosproject.ui.impl.topo; |
| 19 | |
| 20 | import org.onosproject.ui.UiTopo2Overlay; |
| 21 | import org.slf4j.Logger; |
| 22 | import org.slf4j.LoggerFactory; |
| 23 | |
| 24 | import java.util.Collection; |
| 25 | import java.util.HashMap; |
| 26 | import java.util.Map; |
| 27 | |
| 28 | import static com.google.common.base.Strings.isNullOrEmpty; |
| 29 | |
| 30 | /** |
| 31 | * A cache of {@link org.onosproject.ui.UiTopo2Overlay}'s that were |
| 32 | * registered at the time the UI connection was established. |
| 33 | * <p> |
| 34 | * Note, for now, this is a simplified version which will only cache |
| 35 | * a single overlay. At some future point, this should be expanded to mirror |
| 36 | * the behavior of {@link org.onosproject.ui.impl.TopoOverlayCache}. |
| 37 | */ |
| 38 | public class Topo2OverlayCache { |
| 39 | |
| 40 | private final Logger log = LoggerFactory.getLogger(getClass()); |
| 41 | |
| 42 | private static final String EMPTY = ""; |
| 43 | private static final String NO_OVERLAY = "No Overlay"; |
| 44 | private static final String UNKNOWN = "unknown"; |
| 45 | |
| 46 | private static final UiTopo2Overlay NONE = new NullOverlay(); |
| 47 | |
| 48 | private final Map<String, UiTopo2Overlay> overlays = new HashMap<>(); |
| 49 | private UiTopo2Overlay current = null; |
| 50 | |
| 51 | /** |
| 52 | * Constructs the overlay cache. |
| 53 | */ |
| 54 | public Topo2OverlayCache() { |
| 55 | overlays.put(null, NONE); |
| 56 | } |
| 57 | |
| 58 | /** |
| 59 | * Adds a topology-2 overlay to the cache. |
| 60 | * |
| 61 | * @param overlay a topology-2 overlay |
| 62 | */ |
| 63 | public void add(UiTopo2Overlay overlay) { |
| 64 | overlays.put(overlay.id(), overlay); |
| 65 | log.warn("added overlay: " + overlay); |
| 66 | } |
| 67 | |
| 68 | /** |
| 69 | * Invoked when the cache is no longer needed. |
| 70 | */ |
| 71 | public void destroy() { |
| 72 | overlays.clear(); |
| 73 | } |
| 74 | |
| 75 | /** |
| 76 | * Switching currently selected overlay. |
| 77 | * |
| 78 | * @param deact identity of overlay to deactivate |
| 79 | * @param act identity of overlay to activate |
| 80 | */ |
| 81 | public void switchOverlay(String deact, String act) { |
| 82 | UiTopo2Overlay toDeactivate = getOverlay(deact); |
| 83 | UiTopo2Overlay toActivate = getOverlay(act); |
| 84 | |
| 85 | toDeactivate.deactivate(); |
| 86 | current = toActivate; |
| 87 | current.activate(); |
| 88 | } |
| 89 | |
| 90 | private UiTopo2Overlay getOverlay(String id) { |
| 91 | return isNullOrEmpty(id) ? NONE : overlays.get(id); |
| 92 | } |
| 93 | |
| 94 | /** |
| 95 | * Returns the current overlay instance. |
| 96 | * Note that this method always returns a reference; when there is no |
| 97 | * overlay selected the "NULL" overlay instance is returned. |
| 98 | * |
| 99 | * @return the current overlay |
| 100 | */ |
| 101 | public UiTopo2Overlay currentOverlay() { |
| 102 | return current; |
| 103 | } |
| 104 | |
| 105 | /** |
| 106 | * Returns the number of overlays in the cache. Remember that this |
| 107 | * includes the "NULL" overlay, representing "no overlay selected". |
| 108 | * |
| 109 | * @return number of overlays |
| 110 | */ |
| 111 | public int size() { |
| 112 | return overlays.size(); |
| 113 | } |
| 114 | |
| 115 | /** |
| 116 | * Returns true if the identifier of the currently active overlay |
| 117 | * matches the given parameter. |
| 118 | * |
| 119 | * @param overlayId overlay identifier |
| 120 | * @return true if this matches the ID of currently active overlay |
| 121 | */ |
| 122 | public boolean isActive(String overlayId) { |
| 123 | return currentOverlay().id().equals(overlayId); |
| 124 | } |
| 125 | |
| 126 | /** |
| 127 | * Returns the collection of registered overlays. |
| 128 | * |
| 129 | * @return registered overlays |
| 130 | */ |
| 131 | public Collection<UiTopo2Overlay> list() { |
| 132 | return overlays.values(); |
| 133 | } |
| 134 | |
| 135 | // overlay instance representing "no overlay selected" |
| 136 | private static class NullOverlay extends UiTopo2Overlay { |
| 137 | NullOverlay() { |
Simon Hunt | 6cc8645 | 2017-04-27 17:46:22 -0700 | [diff] [blame] | 138 | super(EMPTY); |
Simon Hunt | 22c35df | 2017-04-26 17:28:42 -0700 | [diff] [blame] | 139 | } |
| 140 | } |
| 141 | } |