| package org.onlab.nio; |
| |
| import java.nio.ByteBuffer; |
| import java.nio.channels.ByteChannel; |
| |
| import static com.google.common.base.Preconditions.checkArgument; |
| import static com.google.common.base.Preconditions.checkState; |
| |
| /** |
| * Fixed-length message transfer buffer. |
| */ |
| public class TestMessageStream extends MessageStream<TestMessage> { |
| |
| private static final String E_WRONG_LEN = "Illegal message length: "; |
| private static final long START_TAG = 0xfeedcafedeaddeedL; |
| private static final long END_TAG = 0xbeadcafedeaddeedL; |
| private static final int META_LENGTH = 40; |
| |
| private final int length; |
| private boolean isStrict = true; |
| |
| public TestMessageStream(int length, ByteChannel ch, IOLoop<TestMessage, ?> loop) { |
| super(loop, ch, 64 * 1024, 500); |
| checkArgument(length >= META_LENGTH, "Length must be greater than header length of 40"); |
| this.length = length; |
| } |
| |
| void setNonStrict() { |
| isStrict = false; |
| } |
| |
| @Override |
| protected TestMessage read(ByteBuffer rb) { |
| if (rb.remaining() < length) { |
| return null; |
| } |
| |
| long startTag = rb.getLong(); |
| if (isStrict) { |
| checkState(startTag == START_TAG, "Incorrect message start"); |
| } |
| |
| long size = rb.getLong(); |
| long requestorTime = rb.getLong(); |
| long responderTime = rb.getLong(); |
| byte[] padding = padding(); |
| rb.get(padding); |
| |
| long endTag = rb.getLong(); |
| if (isStrict) { |
| checkState(endTag == END_TAG, "Incorrect message end"); |
| } |
| |
| return new TestMessage((int) size, requestorTime, responderTime, padding); |
| } |
| |
| @Override |
| protected void write(TestMessage message, ByteBuffer wb) { |
| if (message.length() != length) { |
| throw new IllegalArgumentException(E_WRONG_LEN + message.length()); |
| } |
| |
| wb.putLong(START_TAG); |
| wb.putLong(message.length()); |
| wb.putLong(message.requestorTime()); |
| wb.putLong(message.responderTime()); |
| wb.put(message.padding(), 0, length - META_LENGTH); |
| wb.putLong(END_TAG); |
| } |
| |
| public byte[] padding() { |
| return new byte[length - META_LENGTH]; |
| } |
| } |