001 /* 002 * Copyright (C) 2011 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 * 007 * published by the Free Software Foundation; either version 2.1 of 008 * the License, or (at your option) any later version. 009 * 010 * This software is distributed in the hope that it will be useful, 011 * but WITHOUT ANY WARRANTY; without even the implied warranty of 012 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 013 * Lesser General Public License for more details. 014 * 015 * You should have received a copy of the GNU Lesser General Public 016 * License along with this software; if not, write to the Free 017 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 018 * 02110-1301 USA, or see the FSF site: http://www.fsf.org. 019 */ 020 021 package org.crsh.command.impl; 022 023 import org.crsh.command.InvocationContext; 024 import org.crsh.shell.io.ShellPrinter; 025 import org.crsh.util.LineFeedWriter; 026 027 import java.io.StringWriter; 028 import java.util.Collections; 029 import java.util.LinkedList; 030 import java.util.List; 031 import java.util.Map; 032 033 /** 034 * @author <a href="mailto:julien.viet@exoplatform.com">Julien Viet</a> 035 * @version $Revision$ 036 */ 037 public abstract class BaseInvocationContext<C, P> extends BaseCommandContext implements InvocationContext<C, P> { 038 039 /** . */ 040 protected ShellPrinter writer; 041 042 /** . */ 043 protected StringWriter buffer; 044 045 /** . */ 046 protected List<P> producedItems; 047 048 /** . */ 049 protected Iterable<C> consumedItems; 050 051 protected BaseInvocationContext( 052 Iterable<C> consumedItems, 053 Map<String, Object> attributes) { 054 super(attributes); 055 056 // 057 this.writer = null; 058 this.buffer = null; 059 this.consumedItems = consumedItems; 060 this.producedItems = Collections.emptyList(); 061 } 062 063 public List<P> getProducedItems() { 064 return producedItems; 065 } 066 067 public StringWriter getBuffer() { 068 return buffer; 069 } 070 071 public boolean isPiped() { 072 return consumedItems != null; 073 } 074 075 public Iterable<C> consume() { 076 if (consumedItems == null) { 077 throw new IllegalStateException("Cannot consume as no pipe operation is involved"); 078 } 079 return consumedItems; 080 } 081 082 public void produce(P product) { 083 if (producedItems.isEmpty()) { 084 producedItems = new LinkedList<P>(); 085 } 086 producedItems.add(product); 087 } 088 089 public ShellPrinter getWriter() { 090 if (writer == null) { 091 buffer = new StringWriter(); 092 writer = new ShellPrinter(new LineFeedWriter(buffer, "\r\n")); 093 } 094 return writer; 095 } 096 }