一種特殊的Channel實現(xiàn)----EmbeddedChannel茁帽，它是Netty專門為改進針對ChannelHandler的單元測試而提供的。
| 名稱 | 職責 |
|---|---|
| writeInbound | 將入站消息寫到EmbeddedChannel中姐直。如果可以通過readInbound方法從EmbeddedChannel中讀取數(shù)據(jù)，則返回true |
| readInbound | 從EmbeddedChannel中讀取入站消息蒋畜。任何返回東西都經(jīng)過整個ChannelPipeline声畏。如果沒有任何可供讀取的，則返回null |
| writeOutbound | 將出站消息寫到EmbeddedChannel中姻成，如果現(xiàn)在可以通過readOutbound從EmbeddedChannel中讀取到東西插龄，則返回true |
| readOutbound | 從EmbeddedChannel中讀取出站消息。任何返回東西都經(jīng)過整個ChannelPipeline科展。如果沒有任何可供讀取的均牢，則返回null |
| finish | 將EmbeddedChannel標記為完成，如果有可讀取的入站或出站數(shù)據(jù)才睹，則返回true膨处。這個方法還將會調(diào)用EmbeddedChannel上的close方法 |
測試入站消息
public class FixedLengthFrameDecoder extends ByteToMessageDecoder {
private final int frameLength;
public FixedLengthFrameDecoder(int frameLength) {
if (frameLength <= 0) {
throw new IllegalArgumentException("frameLength must be positive integer: " + frameLength);
}
this.frameLength = frameLength;
}
@Override
protected void decode(ChannelHandlerContext ctx, ByteBuf in, List<Object> out) throws Exception {
while (in.readableBytes() >= frameLength) {
ByteBuf buf = in.readBytes(frameLength);
out.add(buf);
}
}
}
public class FixedLengthFrameDecoderTest {
@Test
public void testFramesDecoded() {
ByteBuf buf = Unpooled.buffer();
for (int i = 0; i < 9; i++) {
buf.writeByte(i);
}
ByteBuf input = buf.duplicate();
EmbeddedChannel channel = new EmbeddedChannel(new FixedLengthFrameDecoder(3));
Assert.assertTrue(channel.writeInbound(input.retain()));
Assert.assertTrue(channel.finish());
ByteBuf read = channel.readInbound();
Assert.assertEquals(buf.readSlice(3), read);
read.release();
read = channel.readInbound();
Assert.assertEquals(buf.readSlice(3), read);
read.release();
read = channel.readInbound();
Assert.assertEquals(buf.readSlice(3), read);
read.release();
Assert.assertNull(channel.readInbound());
buf.release();
}
@Test
public void testFramesDecoded2() {
ByteBuf buf = Unpooled.buffer();
for (int i = 0; i < 9; i++) {
buf.writeByte(i);
}
ByteBuf input = buf.duplicate();
EmbeddedChannel channel = new EmbeddedChannel(new FixedLengthFrameDecoder(3));
Assert.assertFalse(channel.writeInbound(input.readBytes(2)));
Assert.assertTrue(channel.writeInbound(input.readBytes(7)));
Assert.assertTrue(channel.finish());
ByteBuf read = channel.readInbound();
Assert.assertEquals(buf.readSlice(3), read);
read.release();
read = channel.readInbound();
Assert.assertEquals(buf.readSlice(3), read);
read.release();
read = channel.readInbound();
Assert.assertEquals(buf.readSlice(3), read);
read.release();
Assert.assertNull(channel.readInbound());
buf.release();
}
}
測試出站消息
public class AbsIntegerEncoder extends MessageToMessageEncoder<ByteBuf> {
@Override
protected void encode(ChannelHandlerContext channelHandlerContext, ByteBuf in, List<Object> out) throws Exception {
while (in.readableBytes() >= 4) {
int value = Math.abs(in.readInt());
out.add(value);
}
}
}
public class AbsIntegerEncoderTest {
@Test
public void testEncoded() {
ByteBuf buf = Unpooled.buffer();
for (int i = 0; i < 10; i++) {
buf.writeInt(i * -1);
}
EmbeddedChannel channel = new EmbeddedChannel(new AbsIntegerEncoder());
Assert.assertTrue(channel.writeOutbound(buf));
Assert.assertTrue(channel.finish());
for (int i = 0; i < 10; i++) {
Assert.assertEquals(Integer.valueOf(i), channel.readOutbound());
}
Assert.assertNull(channel.readOutbound());
}
}
測試異常處理
public class FrameChunkDecoder extends ByteToMessageDecoder {
private final int maxFrameSize;
public FrameChunkDecoder(int maxFrameSize) {
this.maxFrameSize = maxFrameSize;
}
@Override
protected void decode(ChannelHandlerContext ctx, ByteBuf in, List<Object> out) throws Exception {
int readableBytes = in.readableBytes();
if (readableBytes > maxFrameSize) {
in.clear();
throw new TooLongFrameException();
}
ByteBuf buf = in.readBytes(readableBytes);
out.add(buf);
}
}
public class FrameChunkDecoderTest {
@Test
public void testFramesDecoded() {
ByteBuf buf = Unpooled.buffer();
for (int i = 0; i < 9; i++) {
buf.writeByte(i);
}
ByteBuf input = buf.duplicate();
EmbeddedChannel channel = new EmbeddedChannel(new FrameChunkDecoder(3));
Assert.assertTrue(channel.writeInbound(input.readBytes(2)));
try {
channel.writeInbound(input.readBytes(4));
Assert.fail();
} catch (TooLongFrameException e) {
}
Assert.assertTrue(channel.writeInbound(input.readBytes(3)));
Assert.assertTrue(channel.finish());
ByteBuf read = channel.readInbound();
Assert.assertEquals(buf.readSlice(2), read);
read.release();
read = channel.readInbound();
Assert.assertEquals(buf.skipBytes(4).readSlice(3), read);
read.release();
buf.release();
}
}
