/*
* 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.list;
import java.util.List;
import org.apache.geode.cache.Region;
import org.apache.geode.cache.query.Query;
import org.apache.geode.cache.query.SelectResults;
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.RedisDataType;
import org.apache.geode.redis.internal.RedisConstants.ArityDef;
import org.apache.geode.redis.internal.executor.ListQuery;
public class LTrimExecutor extends ListExecutor {
private final String ERROR_KEY_NOT_EXISTS = "The key does not exists on this server";
private final String ERROR_NOT_NUMERIC = "The index provided is not numeric";
private final String SUCCESS = "OK";
@Override
public void executeCommand(Command command, ExecutionHandlerContext context) {
List<byte[]> commandElems = command.getProcessedCommand();
if (commandElems.size() < 4) {
command.setResponse(Coder.getErrorResponse(context.getByteBufAllocator(), ArityDef.LTRIM));
return;
}
ByteArrayWrapper key = command.getKey();
byte[] startArray = commandElems.get(2);
byte[] stopArray = commandElems.get(3);
int redisStart;
int redisStop;
checkDataType(key, RedisDataType.REDIS_LIST, context);
Region keyRegion = getRegion(context, key);
if (keyRegion == null) {
command
.setResponse(Coder.getErrorResponse(context.getByteBufAllocator(), ERROR_KEY_NOT_EXISTS));
return;
}
int listSize = keyRegion.size() - LIST_EMPTY_SIZE;
if (listSize == 0) {
command.setResponse(Coder.getSimpleStringResponse(context.getByteBufAllocator(), SUCCESS));
return;
}
try {
redisStart = Coder.bytesToInt(startArray);
redisStop = Coder.bytesToInt(stopArray);
} catch (NumberFormatException e) {
command.setResponse(Coder.getErrorResponse(context.getByteBufAllocator(), ERROR_NOT_NUMERIC));
return;
}
redisStart = getBoundedStartIndex(redisStart, listSize);
redisStop = getBoundedEndIndex(redisStop, listSize);
redisStart = Math.min(redisStart, listSize - 1);
redisStop = Math.min(redisStop, listSize - 1);
if (redisStart == 0 && redisStop == listSize - 1) {
command.setResponse(Coder.getSimpleStringResponse(context.getByteBufAllocator(), SUCCESS));
return;
} else if (redisStart == 0 && redisStop < redisStart) {
context.getRegionProvider().removeKey(key, RedisDataType.REDIS_LIST);
command.setResponse(Coder.getSimpleStringResponse(context.getByteBufAllocator(), SUCCESS));
return;
}
List<Integer> keepList;
try {
keepList = getRange(context, key, redisStart, redisStop, keyRegion);
} catch (Exception e) {
throw new RuntimeException(e);
}
for (Object keyElement : keyRegion.keySet()) {
if (!keepList.contains(keyElement) && keyElement instanceof Integer)
keyRegion.remove(keyElement);
}
// Reset indexes in meta data region
keyRegion.put("head", keepList.get(0));
keyRegion.put("tail", keepList.get(keepList.size() - 1));
command.setResponse(Coder.getSimpleStringResponse(context.getByteBufAllocator(), SUCCESS));
}
private List<Integer> getRange(ExecutionHandlerContext context, ByteArrayWrapper key, int start,
int stop, Region r) throws Exception {
Query query = getQuery(key, ListQuery.LTRIM, context);
Object[] params = {Integer.valueOf(stop + 1)};
SelectResults<Integer> results = (SelectResults<Integer>) query.execute(params);
if (results == null || results.size() <= start) {
return null;
}
return results.asList().subList(start, results.size());
}
}