讀取 JSch 指令輸出時如何避免死鎖？

<code class="java">ChannelExec channel = (ChannelExec)session.openChannel("exec");

channel.setCommand(...);

ByteArrayOutputStream outputBuffer = new ByteArrayOutputStream();
ByteArrayOutputStream errorBuffer = new ByteArrayOutputStream();

InputStream in = channel.getInputStream();
InputStream err = channel.getExtInputStream();

channel.connect();

while (!channel.isClosed()) {
    // Read stdout continuously
    while (in.available() > 0) {
        outputBuffer.write(in.read(tmp, 0, 1024));
    }

    // Read stderr continuously
    while (err.available() > 0) {
        errorBuffer.write(err.read(tmp, 0, 1024));
    }

    try {
        Thread.sleep(1000);
    } catch (Exception e) {}
}

System.out.println("output: " + outputBuffer.toString("UTF-8"));
System.out.println("error: " + errorBuffer.toString("UTF-8"));

channel.disconnect();</code>