/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package org.apache.karaf.shell.console.completer;
import java.lang.reflect.Field;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashSet;
import java.util.List;
import java.util.Set;
import org.apache.felix.gogo.commands.basic.AbstractCommand;
import org.apache.felix.service.command.CommandProcessor;
import org.apache.felix.service.command.CommandSession;
import org.apache.felix.service.command.Function;
import org.apache.karaf.shell.console.Completer;
import org.apache.karaf.shell.console.jline.CommandSessionHolder;
import org.osgi.framework.BundleContext;
import org.osgi.framework.FrameworkUtil;
import org.osgi.framework.ServiceEvent;
import org.osgi.framework.ServiceListener;
import org.osgi.framework.ServiceReference;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Like the {@link org.apache.karaf.shell.console.completer.CommandsCompleter} but does not use OSGi but is
* instead used from the non-OSGi {@link org.apache.karaf.shell.console.Main}
*/
public class CommandsCompleter implements Completer {
public static final String COMMANDS = ".commands";
private static final Logger LOGGER = LoggerFactory.getLogger(CommandsCompleter.class);
private CommandSession session;
private final List<Completer> completers = new ArrayList<Completer>();
private final Set<String> commands = new HashSet<String>();
public CommandsCompleter() {
this(CommandSessionHolder.getSession());
}
public CommandsCompleter(CommandSession session) {
this.session = session;
try {
new CommandTracker();
} catch (Throwable t) {
// Ignore in case we're not in OSGi
}
}
public int complete(String buffer, int cursor, List<String> candidates) {
if (session == null) {
session = CommandSessionHolder.getSession();
}
checkData();
int res;
synchronized (this) {
res = new AggregateCompleter(completers).complete(buffer, cursor, candidates);
}
Collections.sort(candidates);
return res;
}
protected void checkData() {
// Copy the set to avoid concurrent modification exceptions
// TODO: fix that in gogo instead
Set<String> names;
boolean update;
synchronized (this) {
names = new HashSet<String>((Set<String>) session.get(COMMANDS));
update = !names.equals(commands);
}
if (update) {
// get command aliases
Set<String> aliases = this.getAliases();
Set<String> commands = new HashSet<String>();
List<Completer> completers = new ArrayList<Completer>();
completers.add(new StringsCompleter(aliases));
// add argument completers for each command
for (String command : names) {
Function function = (Function) session.get(command);
function = unProxy(function);
if (function instanceof AbstractCommand) {
try {
completers.add(new ArgumentCompleter(session, (AbstractCommand) function, command));
} catch (Throwable t) {
LOGGER.debug("Unable to create completers for command '" + command + "'", t);
}
}
commands.add(command);
}
synchronized (this) {
this.commands.clear();
this.completers.clear();
this.commands.addAll(commands);
this.completers.addAll(completers);
}
}
}
/**
* Get the aliases defined in the console session.
*
* @return the aliases set
*/
private Set<String> getAliases() {
Set<String> vars = (Set<String>) session.get(null);
Set<String> aliases = new HashSet<String>();
for (String var : vars) {
Object content = session.get(var);
if (content != null && "org.apache.felix.gogo.runtime.Closure".equals(content.getClass().getName())) {
aliases.add(var);
}
}
return aliases;
}
protected Function unProxy(Function function) {
try {
if ("org.apache.felix.gogo.runtime.CommandProxy".equals(function.getClass().getName())) {
Field contextField = function.getClass().getDeclaredField("context");
Field referenceField = function.getClass().getDeclaredField("reference");
contextField.setAccessible(true);
referenceField.setAccessible(true);
BundleContext context = (BundleContext) contextField.get(function);
ServiceReference reference = (ServiceReference) referenceField.get(function);
Object target = context != null ? context.getService(reference) : null;
try {
if (target instanceof Function) {
function = (Function) target;
}
} finally {
if (context != null) {
context.ungetService(reference);
}
}
}
} catch (Throwable t) {
}
return function;
}
private class CommandTracker {
public CommandTracker() throws Exception {
BundleContext context = FrameworkUtil.getBundle(getClass()).getBundleContext();
if (context == null) {
throw new IllegalStateException("Bundle is stopped");
}
ServiceListener listener = new ServiceListener() {
public void serviceChanged(ServiceEvent event) {
synchronized (CommandsCompleter.this) {
commands.clear();
}
}
};
context.addServiceListener(listener,
String.format("(&(%s=*)(%s=*))",
CommandProcessor.COMMAND_SCOPE,
CommandProcessor.COMMAND_FUNCTION));
}
}
}