001/* 002 * Copyright (C) 2012 eXo Platform SAS. 003 * 004 * This is free software; you can redistribute it and/or modify it 005 * under the terms of the GNU Lesser General Public License as 006 * published by the Free Software Foundation; either version 2.1 of 007 * the License, or (at your option) any later version. 008 * 009 * This software is distributed in the hope that it will be useful, 010 * but WITHOUT ANY WARRANTY; without even the implied warranty of 011 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 012 * Lesser General Public License for more details. 013 * 014 * You should have received a copy of the GNU Lesser General Public 015 * License along with this software; if not, write to the Free 016 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 017 * 02110-1301 USA, or see the FSF site: http://www.fsf.org. 018 */ 019 020package org.crsh.shell; 021 022import java.io.IOException; 023 024/** 025 * The interaction context extends the screen context and provides interaction with the client. 026 */ 027public interface InteractionContext extends ScreenContext { 028 029 /** 030 * Take control of the alternate buffer. When the alternate buffer is already used 031 * nothing happens. The buffer switch should occur when then {@link #flush()} method 032 * is invoked. 033 * 034 * @return true if the alternate buffer is shown 035 */ 036 boolean takeAlternateBuffer() throws IOException; 037 038 /** 039 * Release control of the alternate buffer. When the normal buffer is already used 040 * nothing happens. The buffer switch should occur when then {@link #flush()} method 041 * is invoked. 042 * 043 * @return true if the usual buffer is shown 044 */ 045 boolean releaseAlternateBuffer() throws IOException; 046 047 /** 048 * Returns a generic property, usually this property is resolved by the 049 * shell client. 050 * 051 * @param propertyName the property name 052 * @return the property value 053 */ 054 String getProperty(String propertyName); 055 056 /** 057 * Display a message and read a line on the console, this method call can be blocking until the user provides 058 * a value. If no line can be read then null is returned. 059 * 060 * @param msg the message to display before reading a line 061 * @param echo wether or not the line read should be echoed when typing 062 * @return the line read 063 * @throws java.io.IOException any io exception 064 * @throws java.lang.InterruptedException the thread was interrupted while waiting for the user value 065 * @throws java.lang.IllegalStateException if reading a line is not at the appropriate time 066 */ 067 String readLine(String msg, boolean echo) throws IOException, InterruptedException, IllegalStateException; 068 069}