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 package org.crsh.lang;
020
021 import org.crsh.lang.impl.script.ScriptCompiler;
022 import org.crsh.lang.spi.Compiler;
023 import org.crsh.lang.spi.Language;
024 import org.crsh.plugin.PluginContext;
025 import org.crsh.plugin.ResourceKind;
026 import org.crsh.shell.impl.command.spi.Command;
027 import org.crsh.shell.impl.command.spi.CommandException;
028 import org.crsh.shell.impl.command.spi.CommandResolver;
029 import org.crsh.lang.spi.CommandResolution;
030 import org.crsh.util.TimestampedObject;
031 import org.crsh.vfs.Resource;
032
033 import java.util.HashMap;
034 import java.util.LinkedHashMap;
035 import java.util.Map;
036 import java.util.concurrent.ConcurrentHashMap;
037
038 /**
039 * A shell command resolver for languages.
040 *
041 * @author Julien Viet
042 */
043 public class LanguageCommandResolver implements CommandResolver {
044
045 /** . */
046 private final Map<String, TimestampedObject<CommandResolution>> commandCache = new ConcurrentHashMap<String, TimestampedObject<CommandResolution>>();
047
048 /** . */
049 final HashMap<String, Compiler> activeCompilers = new HashMap<String, Compiler>();
050
051 /** . */
052 final PluginContext context;
053
054 public LanguageCommandResolver(PluginContext context) {
055
056 //
057 activeCompilers.put("script", ScriptCompiler.getInstance());
058
059 //
060 for (Language lang : context.getPlugins(Language.class)) {
061 if (lang.isActive()) {
062 Compiler compiler = lang.getCompiler();
063 if (compiler != null) {
064 for (String ext : compiler.getExtensions()) {
065 activeCompilers.put(ext, compiler);
066 }
067 }
068 }
069 }
070
071 this.context = context;
072 }
073
074 public Compiler getCompiler(String name) {
075 return activeCompilers.get(name);
076 }
077
078 @Override
079 public Iterable<Map.Entry<String, String>> getDescriptions() {
080 LinkedHashMap<String, String> commands = new LinkedHashMap<String, String>();
081 for (String resourceName : context.listResources(ResourceKind.COMMAND)) {
082 int index = resourceName.indexOf('.');
083 String name = resourceName.substring(0, index);
084 String ext = resourceName.substring(index + 1);
085 if (activeCompilers.containsKey(ext)) {
086 try {
087 CommandResolution resolution = resolveCommand2(name);
088 commands.put(name, resolution.getDescription());
089 }
090 catch (CommandException e) {
091 //
092 }
093 }
094 }
095 return commands.entrySet();
096 }
097
098 @Override
099 public Command<?> resolveCommand(String name) throws CommandException, NullPointerException {
100 CommandResolution resolution = resolveCommand2(name);
101 return resolution != null ? resolution.getCommand() : null;
102 }
103
104 private CommandResolution resolveCommand2(String name) throws CommandException, NullPointerException {
105 for (Compiler manager : activeCompilers.values()) {
106 for (String ext : manager.getExtensions()) {
107 Iterable<Resource> resources = context.loadResources(name + "." + ext, ResourceKind.COMMAND);
108 for (Resource resource : resources) {
109 CommandResolution resolution = resolveCommand(manager, name, resource);
110 if (resolution != null) {
111 return resolution;
112 }
113 }
114 }
115 }
116 return null;
117 }
118
119 private CommandResolution resolveCommand(org.crsh.lang.spi.Compiler manager, String name, Resource script) throws CommandException {
120 TimestampedObject<CommandResolution> ref = commandCache.get(name);
121 if (ref != null) {
122 if (script.getTimestamp() != ref.getTimestamp()) {
123 ref = null;
124 }
125 }
126 CommandResolution command;
127 if (ref == null) {
128 command = manager.compileCommand(name, script.getContent());
129 if (command != null) {
130 commandCache.put(name, new TimestampedObject<CommandResolution>(script.getTimestamp(), command));
131 }
132 } else {
133 command = ref.getObject();
134 }
135 return command;
136 }
137
138 }