| 1 | /* |
| 2 | * Copyright (C) 2015 - EfficiOS Inc., Alexandre Montplaisir <alexmonthy@efficios.com> |
| 3 | * Copyright (C) 2013 - David Goulet <dgoulet@efficios.com> |
| 4 | * |
| 5 | * This library is free software; you can redistribute it and/or modify it |
| 6 | * under the terms of the GNU Lesser General Public License, version 2.1 only, |
| 7 | * as published by the Free Software Foundation. |
| 8 | * |
| 9 | * This library is distributed in the hope that it will be useful, but WITHOUT |
| 10 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| 11 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License |
| 12 | * for more details. |
| 13 | * |
| 14 | * You should have received a copy of the GNU Lesser General Public License |
| 15 | * along with this library; if not, write to the Free Software Foundation, |
| 16 | * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| 17 | */ |
| 18 | |
| 19 | package org.lttng.ust.agent.client; |
| 20 | |
| 21 | import java.nio.ByteBuffer; |
| 22 | import java.nio.ByteOrder; |
| 23 | |
| 24 | /** |
| 25 | * Interface for all response messages sent from the Java agent to the sessiond |
| 26 | * daemon. Normally sent after a command coming from the session daemon was |
| 27 | * executed. |
| 28 | * |
| 29 | * @author Alexandre Montplaisir |
| 30 | */ |
| 31 | abstract class LttngAgentResponse { |
| 32 | |
| 33 | private static final int INT_SIZE = 4; |
| 34 | |
| 35 | /** |
| 36 | * Return codes used in agent responses, to indicate success or different |
| 37 | * types of failures of the commands. |
| 38 | */ |
| 39 | protected enum ReturnCode { |
| 40 | |
| 41 | CODE_SUCCESS_CMD(1), |
| 42 | CODE_INVALID_CMD(2), |
| 43 | CODE_UNK_LOGGER_NAME(3); |
| 44 | |
| 45 | private int code; |
| 46 | |
| 47 | private ReturnCode(int c) { |
| 48 | code = c; |
| 49 | } |
| 50 | |
| 51 | public int getCode() { |
| 52 | return code; |
| 53 | } |
| 54 | } |
| 55 | |
| 56 | /** |
| 57 | * Get the {@link ReturnCode} that goes with this response. It is expected |
| 58 | * by the session daemon, but some commands may require more than this |
| 59 | * in their response. |
| 60 | * |
| 61 | * @return The return code |
| 62 | */ |
| 63 | public abstract ReturnCode getReturnCode(); |
| 64 | |
| 65 | /** |
| 66 | * Gets a byte array of the response so that it may be streamed. |
| 67 | * |
| 68 | * @return The byte array of the response |
| 69 | */ |
| 70 | public byte[] getBytes() { |
| 71 | byte data[] = new byte[INT_SIZE]; |
| 72 | ByteBuffer buf = ByteBuffer.wrap(data); |
| 73 | buf.order(ByteOrder.BIG_ENDIAN); |
| 74 | buf.putInt(getReturnCode().getCode()); |
| 75 | return data; |
| 76 | } |
| 77 | |
| 78 | public static final LttngAgentResponse SUCESS_RESPONSE = new LttngAgentResponse() { |
| 79 | @Override |
| 80 | public ReturnCode getReturnCode() { |
| 81 | return ReturnCode.CODE_SUCCESS_CMD; |
| 82 | } |
| 83 | }; |
| 84 | |
| 85 | public static final LttngAgentResponse FAILURE_RESPONSE = new LttngAgentResponse() { |
| 86 | @Override |
| 87 | public ReturnCode getReturnCode() { |
| 88 | return ReturnCode.CODE_INVALID_CMD; |
| 89 | } |
| 90 | }; |
| 91 | } |