重庆分公司,新征程启航

为企业提供网站建设、域名注册、服务器等服务

netty使用EmbeddedChannel对channel

一种特殊的Channel实现----EmbeddedChannel,它是Netty专门为改进针对ChannelHandler的单元测试而提供的。

创新互联建站拥有网站维护技术和项目管理团队,建立的售前、实施和售后服务体系,为客户提供定制化的成都网站设计、成都网站制作、网站维护、成都移动云计算中心解决方案。为客户网站安全和日常运维提供整体管家式外包优质服务。我们的网站维护服务覆盖集团企业、上市公司、外企网站、商城开发、政府网站等各类型客户群体,为全球上千余家企业提供全方位网站维护、服务器维护解决方案。

名称职责
writeInbound 将入站消息写到EmbeddedChannel中。如果可以通过readInbound方法从EmbeddedChannel中读取数据,则返回true
readInbound 从EmbeddedChannel中读取入站消息。任何返回东西都经过整个ChannelPipeline。如果没有任何可供读取的,则返回null
writeOutbound 将出站消息写到EmbeddedChannel中,如果现在可以通过readOutbound从EmbeddedChannel中读取到东西,则返回true
readOutbound 从EmbeddedChannel中读取出站消息。任何返回东西都经过整个ChannelPipeline。如果没有任何可供读取的,则返回null
finish 将EmbeddedChannel标记为完成,如果有可读取的入站或出站数据,则返回true。这个方法还将会调用EmbeddedChannel上的close方法

测试入站消息

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 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();
    }
}

测试出站消息

public class AbsIntegerEncoder extends MessageToMessageEncoder {
    @Override
    protected void encode(ChannelHandlerContext channelHandlerContext, ByteBuf in, List 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());
    }
}

测试异常处理

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 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();
    }
}

网页名称:netty使用EmbeddedChannel对channel
网页路径:http://cqcxhl.cn/article/pipgcp.html