/**
* 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.waveprotocol.wave.client.wavepanel.event;
import org.waveprotocol.wave.client.common.util.KeyCombo;
import java.util.EnumMap;
/**
* A by-key registry of key handlers. At most one handler is permitted for any
* one key combination.
*
*/
public final class KeySignalRouter implements KeySignalHandler {
private final EnumMap<KeyCombo, KeySignalHandler> handlers =
new EnumMap<KeyCombo, KeySignalHandler>(KeyCombo.class);
/**
* Creates a signal router.
*/
static KeySignalRouter create() {
return new KeySignalRouter();
}
/**
* Registers a key handler for a set of keys.
*
* @param keys keys to handle
* @param handler handler for {@code keys}
* @throws IllegalArgumentException if there is already a handler registered
* for any of the keys in {@code keys}.
*/
public void register(Iterable<KeyCombo> keys, KeySignalHandler handler) {
for (KeyCombo key : keys) {
if (handlers.containsKey(key)) {
throw new IllegalArgumentException(
"Feature conflict: multiple handlers registered for key " + key);
}
handlers.put(key, handler);
}
}
@Override
public boolean onKeySignal(KeyCombo key) {
KeySignalHandler handler = handlers.get(key);
return (handler != null) ? handler.onKeySignal(key) : false;
}
}