/*
* 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.geode.redis.internal.executor.string;
import java.util.List;
import org.apache.geode.cache.Region;
import org.apache.geode.redis.internal.ByteArrayWrapper;
import org.apache.geode.redis.internal.Coder;
import org.apache.geode.redis.internal.Command;
import org.apache.geode.redis.internal.ExecutionHandlerContext;
import org.apache.geode.redis.internal.RedisConstants.ArityDef;
import org.apache.geode.redis.internal.RedisDataType;
import org.apache.geode.redis.internal.RegionProvider;
public class DecrExecutor extends StringExecutor {
private final String ERROR_VALUE_NOT_USABLE =
"The value at this key cannot be decremented numerically";
private final String ERROR_OVERFLOW = "This decrementation cannot be performed due to overflow";
private final byte[] INIT_VALUE_BYTES = Coder.stringToBytes("-1");
private final int INIT_VALUE_INT = -1;
@Override
public void executeCommand(Command command, ExecutionHandlerContext context) {
List<byte[]> commandElems = command.getProcessedCommand();
RegionProvider rC = context.getRegionProvider();
Region<ByteArrayWrapper, ByteArrayWrapper> r = rC.getStringsRegion();;
if (commandElems.size() < 2) {
command.setResponse(Coder.getErrorResponse(context.getByteBufAllocator(), ArityDef.DECR));
return;
}
ByteArrayWrapper key = command.getKey();
checkAndSetDataType(key, context);
ByteArrayWrapper valueWrapper = r.get(key);
/*
* Value does not exist
*/
if (valueWrapper == null) {
byte[] newValue = INIT_VALUE_BYTES;
r.put(key, new ByteArrayWrapper(newValue));
rC.metaPut(key, RedisDataType.REDIS_STRING);
command.setResponse(Coder.getIntegerResponse(context.getByteBufAllocator(), INIT_VALUE_INT));
return;
}
/*
* Value exists
*/
String stringValue = valueWrapper.toString();
Long value;
try {
value = Long.parseLong(stringValue);
} catch (NumberFormatException e) {
command.setResponse(
Coder.getErrorResponse(context.getByteBufAllocator(), ERROR_VALUE_NOT_USABLE));
return;
}
if (value == Long.MIN_VALUE) {
command.setResponse(Coder.getErrorResponse(context.getByteBufAllocator(), ERROR_OVERFLOW));
return;
}
value--;
stringValue = "" + value;
r.put(key, new ByteArrayWrapper(Coder.stringToBytes(stringValue)));
command.setResponse(Coder.getIntegerResponse(context.getByteBufAllocator(), value));
}
}