001 /* 002 * Copyright (C) 2003-2009 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 */ 019 020 package org.crsh.command; 021 022 import java.io.PrintWriter; 023 024 /** 025 * The invocation context provided to a command during the invocation phase. The invocation context provides the 026 * various interactions that a command can perform with its context during its invocation. 027 * 028 * @author <a href="mailto:julien.viet@exoplatform.com">Julien Viet</a> 029 * @version $Revision$ 030 */ 031 public interface InvocationContext<C, P> extends CommandContext { 032 033 /** 034 * Returns the term width in chars. When the value is not positive it means the value could not be determined. 035 * 036 * @return the term width 037 */ 038 int getWidth(); 039 040 /** 041 * Returns a generic property. 042 * 043 * @param propertyName the property name 044 * @return the property value 045 */ 046 String getProperty(String propertyName); 047 048 /** 049 * Display a message and read a line on the console. 050 * 051 * @param msg the message to display before reading a line 052 * @param echo wether or not the line read should be echoed when typing 053 * @return the line read 054 */ 055 String readLine(String msg, boolean echo); 056 057 /** 058 * Returns the writer for the output. 059 * 060 * @return the writer 061 */ 062 PrintWriter getWriter(); 063 064 /** 065 * Returns true if the command is involved in a pipe operation and receives a stream. 066 * 067 * @return true if the command is involved in a pipe 068 */ 069 boolean isPiped(); 070 071 /** 072 * Returns an iterator over the stream of consumed items. 073 * 074 * @return the consumed items 075 * @throws IllegalStateException if the command is not involved in a pipe operation 076 */ 077 Iterable<C> consume() throws IllegalStateException; 078 079 /** 080 * Produce an item. 081 * 082 * @param product the item product 083 */ 084 void produce(P product); 085 086 }