001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017package org.apache.juneau.terminal.region;
018
019import java.io.*;
020
021/**
022 * Where a caller's keystrokes go: the input end of one running terminal job.
023 */
024public interface TerminalSink {
025
026   /**
027    * Whether input is accepted right now.
028    *
029    * @return <jk>false</jk> once the process has ended or a write has failed.
030    */
031   boolean acceptsInput();
032
033   /**
034    * Hands the bytes to the process.
035    *
036    * <p>
037    * Must not block the caller (it runs on the WebSocket thread).  Never throws for a closed or broken pipe: that
038    * turns {@link #acceptsInput()} false instead.
039    *
040    * @param bytes The bytes to send.
041    * @return <jk>false</jk> when the bytes were not taken because the sink's pending-input buffer is full.
042    * @throws IOException On an unexpected I/O failure.
043    */
044   boolean write(byte[] bytes) throws IOException;
045}