| /** |
| * |
| * Copyright 2005-2006 The Apache Software Foundation or its licensors, as applicable. |
| * |
| * 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 org.apache.xbean.kernel; |
| |
| import java.io.Serializable; |
| |
| /** |
| * The state of services within the Kernel. The state model is directly adapted from the J2EE Management Specification |
| * (JSR 77) with the removal of the FAILED state. |
| * |
| * @author Dain Sundstrom |
| * @version $Id$ |
| * @since 2.0 |
| */ |
| public final class ServiceState implements Serializable { |
| private static final long serialVersionUID = -2629672602273580572L; |
| |
| /** |
| * This state indicates that the service is attempting to start but has not fully started yet. Normally, a service |
| * in this state is waiting for a required service to enter the RUNNING state. |
| */ |
| public static final ServiceState STARTING = new ServiceState((byte) 0, "STARTING"); |
| |
| /** |
| * This state indicates that the service is in the normal operational state. |
| */ |
| public static final ServiceState RUNNING = new ServiceState((byte) 1, "RUNNING"); |
| |
| /** |
| * This state indicates that the service is attempting to stop but has not fully stopped yet. Normally, a service |
| * in this state because another service is still usind this service. |
| */ |
| public static final ServiceState STOPPING = new ServiceState((byte) 2, "STOPPING"); |
| |
| /** |
| * This state indicates that the service is stopped and not operational. |
| */ |
| public static final ServiceState STOPPED = new ServiceState((byte) 3, "STOPPED"); |
| |
| /** |
| * A quick index for looking up service states. |
| */ |
| private static final ServiceState[] serviceStateIndex = new ServiceState[]{STARTING, RUNNING, STOPPING, STOPPED}; |
| |
| static { |
| for (int i = 0; i < serviceStateIndex.length; i++) { |
| ServiceState serviceState = serviceStateIndex[i]; |
| if (serviceState.getIndex() != i) { |
| throw new AssertionError(serviceState + " state index is " + serviceState.getIndex() + |
| ", but is located at index " + i + " in the serviceStateIndex"); |
| } |
| } |
| } |
| |
| /** |
| * Converts the state index into corresponding state name. |
| * |
| * @param state the state index |
| * @return the name of the state |
| * @throws IllegalArgumentException if the state index is not 0, 1, 2 or 3 |
| */ |
| public static ServiceState getServiceState(int state) throws IllegalArgumentException { |
| if (state < 0 || state >= serviceStateIndex.length) { |
| throw new IllegalArgumentException("Unknown state " + state); |
| } |
| return serviceStateIndex[state]; |
| } |
| |
| /** |
| * Converts the state name in the corresponding state index. This method performs a case insensitive comparison. |
| * |
| * @param state the state name |
| * @return the state index |
| * @throws IllegalArgumentException if the state index is not STARTING, RUNNING, STOPPING or FAILED |
| */ |
| public static ServiceState parseServiceState(String state) { |
| if (state == null) throw new NullPointerException("state is null"); |
| if (STARTING.toString().equalsIgnoreCase(state)) { |
| return STARTING; |
| } else if (RUNNING.toString().equalsIgnoreCase(state)) { |
| return RUNNING; |
| } else if (STOPPING.toString().equalsIgnoreCase(state)) { |
| return STOPPING; |
| } else if (STOPPED.toString().equalsIgnoreCase(state)) { |
| return STOPPED; |
| } else { |
| throw new IllegalArgumentException("Unknown state " + state); |
| } |
| } |
| |
| private final byte index; |
| private final transient String name; |
| |
| private ServiceState(byte index, String name) { |
| this.index = index; |
| this.name = name; |
| } |
| |
| /** |
| * Gets the unique index of this state. This index can be be used to retrieve this state instance using the |
| * getServiceState(int) method. |
| * |
| * @return the unique index of this state |
| */ |
| public int getIndex() { |
| return index; |
| } |
| |
| /** |
| * The unique name of this state. This uppercase name can be used to retrieve this state instance using the |
| * parseServiceState(String). |
| * |
| * @return the unique name of this state |
| */ |
| public String getName() { |
| return name; |
| } |
| |
| /** |
| * Returns the name of this state. |
| * |
| * @return the unique name of this state |
| */ |
| public String toString() { |
| return name; |
| } |
| |
| private Object readResolve() { |
| return serviceStateIndex[index]; |
| } |
| } |