SemaphoreResult.java

/*******************************************************************************
 * Copyright (c) 2009  Clark N. Hobbie
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     Clark N. Hobbie - initial API and implementation
 *******************************************************************************/
package org.eclipse.ecf.ipc.semaphore;

/**
 * <P>
 * An internal class that contains the results from a native system call.
 * </P>
 * <P>
 * Calls to the underlying operation system will often have sever pieces of information
 * instead of just success and failure. This class allows clients to get back all the
 * information at once.
 * </P>
 * <P>
 * The RESULT_ constants are defined to make life easier for the JNI: accessing enum tags
 * in JNI is somewhat difficult.
 * </P>
 * 
 * @author Clark N. Hobbie
 */
public class SemaphoreResult
{
	public static final int RESULT_SUCCESS = 0;

	public static final int RESULT_INSUFFICIENT_PERMISSIONS = 1;

	public static final int RESULT_DOES_NOT_EXIST = 2;

	public static final int RESULT_UNKNOWN_ERROR = 3;

	public static final int RESULT_TIMEOUT = 4;

	public static final int RESULT_UNKNOWN_HANDLE = 5;

	public static final String MSG_INSUFFICIENT_PERMISSIONS = "Insufficient permissions to access the semaphore";

	public static final String MSG_SUCCESS = "success";

	public static final String MSG_DOES_NOT_EXIST = "The semaphore does not exist";

	public static final String MSG_UNKNOWN_ERROR = "An unknown error occurred while trying to access the semaphore";

	public static final String MSG_TIMEOUT = "The specified period of timeout elapsed before the semaphore became available";

	public static final String MSG_UNKNOWN_HANDLE = "The specified handle was not recognized as a semaphore handle by the OS";

	public enum Results
	{
		Success(RESULT_SUCCESS, MSG_SUCCESS), 
		InsufficientPermissions(RESULT_INSUFFICIENT_PERMISSIONS, MSG_INSUFFICIENT_PERMISSIONS), 
		DoesNotExist(RESULT_DOES_NOT_EXIST, MSG_DOES_NOT_EXIST), 
		UnknownError(RESULT_UNKNOWN_ERROR, MSG_UNKNOWN_ERROR), 
		Timeout(RESULT_TIMEOUT, MSG_TIMEOUT), 
		UnknownHandle(RESULT_UNKNOWN_HANDLE, MSG_UNKNOWN_HANDLE);

		public String message;

		public int code;

		private Results(int resultCode, String theMessage)
		{
			code = resultCode;
			message = theMessage;
		}

		public static Results toResult(int code)
		{
			Results result = UnknownError;

			for (Results r : values())
			{
				if (code == r.code)
				{
					result = r;
					break;
				}
			}

			return result;
		}

		public static int foo()
		{
			return -1;
		}
	}

	public void convertResultCode()
	{
		result = Results.toResult(resultCode);
	}

	public int resultCode;

	public Results result;

	public int errorCode;

	public long handle;
}