| /* |
| * 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.samza.util; |
| |
| import java.util.HashMap; |
| import java.util.Map; |
| import java.util.Set; |
| import org.apache.samza.Partition; |
| import org.apache.samza.system.SystemAdmin; |
| import org.apache.samza.system.SystemStreamMetadata; |
| import org.apache.samza.system.SystemStreamMetadata.SystemStreamPartitionMetadata; |
| import org.apache.samza.system.SystemStreamPartition; |
| |
| /** |
| * A simple helper admin class that defines a single partition (partition 0) for |
| * a given system. The metadata uses null for all offsets, which means that the |
| * stream doesn't support offsets, and will be treated as empty. This class |
| * should be used when a system has no concept of partitioning or offsets, since |
| * Samza needs at least one partition for an input stream, in order to read it. |
| */ |
| public class SinglePartitionWithoutOffsetsSystemAdmin implements SystemAdmin { |
| private static final Map<Partition, SystemStreamPartitionMetadata> fakePartitionMetadata = new HashMap<Partition, SystemStreamPartitionMetadata>(); |
| |
| static { |
| fakePartitionMetadata.put(new Partition(0), new SystemStreamPartitionMetadata(null, null, null)); |
| } |
| |
| @Override |
| public Map<String, SystemStreamMetadata> getSystemStreamMetadata(Set<String> streamNames) { |
| Map<String, SystemStreamMetadata> metadata = new HashMap<String, SystemStreamMetadata>(); |
| |
| for (String streamName : streamNames) { |
| metadata.put(streamName, new SystemStreamMetadata(streamName, fakePartitionMetadata)); |
| } |
| |
| return metadata; |
| } |
| |
| @Override |
| public Map<SystemStreamPartition, String> getOffsetsAfter(Map<SystemStreamPartition, String> offsets) { |
| Map<SystemStreamPartition, String> offsetsAfter = new HashMap<SystemStreamPartition, String>(); |
| |
| for (SystemStreamPartition systemStreamPartition : offsets.keySet()) { |
| offsetsAfter.put(systemStreamPartition, null); |
| } |
| |
| return offsetsAfter; |
| } |
| } |