从单个线程可以使用：

InputStream input = process.getInputStream();
OutputStream output = process.getOutputStream();

byte[] buffer = new byte[8192];
int amountRead;
while ((amountRead = input.read(buffer)) != -1) {
    output.write(buffer, 0, amountRead);
}

如果要使用两个线程，可以使用 PipedInputStream 以及 PipedOutputStream :

PipedOutputStream producer = new PipedOutputStream();
PipedInputStream consumer = new PipedInputStream(producer);

// This thread reads the input from one process, and publishes it to another thread
byte[] buffer = new byte[8192];
int amountRead;
while ((amountRead = input.read(buffer)) != -1) {
    producer.write(buffer, 0, amountRead);
}

// This thread consumes what has been published, and writes it to another process
byte[] buffer = new byte[8192];
int amountRead;
while ((amountRead = consumer.read(buffer)) != -1) {
    output.write(buffer, 0, amountRead);
}