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 */ 019package org.crsh.lang.groovy.closure; 020 021import groovy.lang.Closure; 022import org.crsh.command.CommandContext; 023import org.crsh.shell.impl.command.spi.CommandInvoker; 024 025import java.io.IOException; 026 027/** @author Julien Viet */ 028public class ClosureInvoker extends CommandInvoker<Object, Object> { 029 030 /** . */ 031 private final Closure closure; 032 033 /** . */ 034 private final Class<?> type; 035 036 /** . */ 037 private CommandContext<? super Object> consumer; 038 039 public ClosureInvoker(Closure closure) { 040 041 // Resolve the closure consumed type 042 final Class<?> type; 043 Class[] parameterTypes = closure.getParameterTypes(); 044 if (parameterTypes != null && parameterTypes.length > 0) { 045 type = parameterTypes[0]; 046 } else { 047 type = Object.class; 048 } 049 050 // 051 this.type = type; 052 this.closure = closure; 053 } 054 055 public Class<Object> getProducedType() { 056 return Object.class; 057 } 058 public Class<Object> getConsumedType() { 059 return Object.class; 060 } 061 public void provide(Object element) throws IOException { 062 if (type.isInstance(element)) { 063 Object ret = closure.call(element); 064 if (ret != null) { 065 consumer.provide(ret); 066 } 067 } 068 } 069 070 public void open(CommandContext<? super Object> consumer) { 071 this.consumer = consumer; 072 ClosureDelegate delegate = new ClosureDelegate(consumer, closure.getOwner()); 073 closure.setResolveStrategy(Closure.DELEGATE_FIRST); 074 closure.setDelegate(delegate); 075 } 076 077 public void flush() throws IOException { 078 consumer.flush(); 079 } 080 081 public void close() { 082 consumer = null; 083 } 084}