| /* |
| * Copyright (C) 2018 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package com.example.android.systemupdatersample; |
| |
| import android.util.SparseArray; |
| |
| import com.google.common.collect.ImmutableMap; |
| import com.google.common.collect.ImmutableSet; |
| |
| import java.util.concurrent.atomic.AtomicInteger; |
| |
| /** |
| * Controls updater state. |
| */ |
| public class UpdaterState { |
| |
| public static final int IDLE = 0; |
| public static final int ERROR = 1; |
| public static final int RUNNING = 2; |
| public static final int PAUSED = 3; |
| public static final int SLOT_SWITCH_REQUIRED = 4; |
| public static final int REBOOT_REQUIRED = 5; |
| |
| private static final SparseArray<String> STATE_MAP = new SparseArray<>(); |
| |
| static { |
| STATE_MAP.put(0, "IDLE"); |
| STATE_MAP.put(1, "ERROR"); |
| STATE_MAP.put(2, "RUNNING"); |
| STATE_MAP.put(3, "PAUSED"); |
| STATE_MAP.put(4, "SLOT_SWITCH_REQUIRED"); |
| STATE_MAP.put(5, "REBOOT_REQUIRED"); |
| } |
| |
| /** |
| * Allowed state transitions. It's a map: key is a state, value is a set of states that |
| * are allowed to transition to from key. |
| */ |
| private static final ImmutableMap<Integer, ImmutableSet<Integer>> TRANSITIONS = |
| ImmutableMap.<Integer, ImmutableSet<Integer>>builder() |
| .put(IDLE, ImmutableSet.of(IDLE, ERROR, RUNNING)) |
| .put(ERROR, ImmutableSet.of(IDLE)) |
| .put(RUNNING, ImmutableSet.of( |
| IDLE, ERROR, PAUSED, REBOOT_REQUIRED, SLOT_SWITCH_REQUIRED)) |
| .put(PAUSED, ImmutableSet.of(ERROR, RUNNING, IDLE)) |
| .put(SLOT_SWITCH_REQUIRED, ImmutableSet.of(ERROR, REBOOT_REQUIRED, IDLE)) |
| .put(REBOOT_REQUIRED, ImmutableSet.of(IDLE)) |
| .build(); |
| |
| private AtomicInteger mState; |
| |
| public UpdaterState(int state) { |
| this.mState = new AtomicInteger(state); |
| } |
| |
| /** |
| * Returns updater state. |
| */ |
| public int get() { |
| return mState.get(); |
| } |
| |
| /** |
| * Sets the updater state. |
| * |
| * @throws InvalidTransitionException if transition is not allowed. |
| */ |
| public void set(int newState) throws InvalidTransitionException { |
| int oldState = mState.get(); |
| if (!TRANSITIONS.get(oldState).contains(newState)) { |
| throw new InvalidTransitionException( |
| "Can't transition from " + oldState + " to " + newState); |
| } |
| mState.set(newState); |
| } |
| |
| /** |
| * Converts status code to status name. |
| */ |
| public static String getStateText(int state) { |
| return STATE_MAP.get(state); |
| } |
| |
| /** |
| * Defines invalid state transition exception. |
| */ |
| public static class InvalidTransitionException extends Exception { |
| public InvalidTransitionException(String msg) { |
| super(msg); |
| } |
| } |
| } |