Java tutorial
/* * Copyright (c) 2015 Spotify AB. * * 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 com.spotify.heroic.metadata; import com.google.common.collect.ImmutableList; import com.google.common.collect.ImmutableSet; import com.spotify.heroic.cluster.ClusterShard; import com.spotify.heroic.common.DateRange; import com.spotify.heroic.common.OptionalLimit; import com.spotify.heroic.filter.Filter; import com.spotify.heroic.metric.RequestError; import com.spotify.heroic.metric.ShardError; import eu.toolchain.async.Collector; import eu.toolchain.async.Transform; import lombok.Data; import java.util.ArrayList; import java.util.HashSet; import java.util.List; import java.util.Set; @Data public class FindKeys { private final List<RequestError> errors; private final Set<String> keys; private final int size; private final int duplicates; public static FindKeys of() { return new FindKeys(ImmutableList.of(), ImmutableSet.of(), 0, 0); } public static FindKeys of(final Set<String> keys, int size, int duplicates) { return new FindKeys(ImmutableList.of(), keys, size, duplicates); } public static Collector<FindKeys, FindKeys> reduce() { return results -> { final List<RequestError> errors = new ArrayList<>(); final Set<String> keys = new HashSet<>(); int size = 0; int duplicates = 0; for (final FindKeys result : results) { errors.addAll(result.errors); for (final String k : result.keys) { if (keys.add(k)) { duplicates += 1; } } duplicates += result.getDuplicates(); size += result.getSize(); } return new FindKeys(errors, keys, size, duplicates); }; } public static Transform<Throwable, FindKeys> shardError(final ClusterShard shard) { return e -> new FindKeys(ImmutableList.of(ShardError.fromThrowable(shard, e)), ImmutableSet.of(), 0, 0); } @Data public static final class Request { private final Filter filter; private final DateRange range; private final OptionalLimit limit; } }