/*
* 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.cassandra.index.sasi.analyzer.filter;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Executes all linked Pipeline Tasks serially and returns
* output (if exists) from the executed logic
*/
public class FilterPipelineExecutor
{
private static final Logger logger = LoggerFactory.getLogger(FilterPipelineExecutor.class);
public static <F,T> T execute(FilterPipelineTask<F, T> task, T initialInput)
{
FilterPipelineTask<?, ?> taskPtr = task;
T result = initialInput;
try
{
while (true)
{
FilterPipelineTask<F,T> taskGeneric = (FilterPipelineTask<F,T>) taskPtr;
result = taskGeneric.process((F) result);
taskPtr = taskPtr.next;
if(taskPtr == null)
return result;
}
}
catch (Exception e)
{
logger.info("An unhandled exception to occurred while processing " +
"pipeline [{}]", task.getName(), e);
}
return null;
}
}