Java NIO Pipe 是两个线程之间的单向数据连接。 Pipe (管道) 具有 source channel (源通道) 和 sink channel (接收器通道) 。 你将数据写入接收器通道，然后可以从源通道读取该数据。

示意图如下：

pipe-internals

基本用法

创建 Pipe

直接调用 open() 方法创建 Pipe. 如下：

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Pipe pipe = Pipe.open();

写入 Pipe

数据先要写入到 sink channel，因此先要获取 sink channel.

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Pipe.SinkChannel sinkChannel = pipe.sink();

写入 sinkChannel ()，如下：

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String newData = "New String to write to file..." + System.currentTimeMillis();

ByteBuffer buf = ByteBuffer.allocate(48);
buf.clear();
buf.put(newData.getBytes());

buf.flip();

while(buf.hasRemaining()) {
    sinkChannel.write(buf);
}

读取 Pipe

从 Pipe 中读取数据，先要获取 soucechannel。如下：

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Pipe.SourceChannel sourceChannel = pipe.source();

调用 read () 方法从 sorce channel 中读取数据，如下：

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ByteBuffer buf = ByteBuffer.allocate(48);

int bytesRead = inChannel.read(buf);

返回的 int 数据，表示已有多少 bytes 读到 buffer 中去了。

示例

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package one.wangwei.java.nio;

import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.channels.Pipe;

public class PipeExample {

    public static void main(String[] args) {
        try {
            //The Pipe is created
            Pipe pipe = Pipe.open();
            //For accessing the pipe sink channel
            Pipe.SinkChannel skChannel = pipe.sink();
            String td = "Data is successfully sent for checking the java NIO Channel Pipe.";
            ByteBuffer bb = ByteBuffer.allocate(512);
            bb.clear();
            bb.put(td.getBytes());
            bb.flip();
            //write the data into a sink channel.
            while (bb.hasRemaining()) {
                skChannel.write(bb);
            }
            //For accessing the pipe source channel
            Pipe.SourceChannel sourceChannel = pipe.source();
            bb = ByteBuffer.allocate(512);
            //The data is write to the console
            while (sourceChannel.read(bb) > 0) {
                bb.flip();
                while (bb.hasRemaining()) {
                    char TestData = (char) bb.get();
                    System.out.print(TestData);
                }
                bb.clear();
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

参考资料