[NO ISSUE][HYR] Add collectors for Int/Long2Object maps
Change-Id: I35ca867f31bd666a53a0da5b506424b22a0ffa74
Reviewed-on: https://asterix-gerrit.ics.uci.edu/c/asterixdb/+/8243
Integration-Tests: Jenkins <jenkins@fulliautomatix.ics.uci.edu>
Tested-by: Jenkins <jenkins@fulliautomatix.ics.uci.edu>
Reviewed-by: Michael Blow <mblow@apache.org>
Reviewed-by: Hussain Towaileb <hussainht@gmail.com>
diff --git a/hyracks-fullstack/hyracks/hyracks-util/pom.xml b/hyracks-fullstack/hyracks/hyracks-util/pom.xml
index b69d509..4993443 100644
--- a/hyracks-fullstack/hyracks/hyracks-util/pom.xml
+++ b/hyracks-fullstack/hyracks/hyracks-util/pom.xml
@@ -99,6 +99,10 @@
<groupId>com.google.guava</groupId>
<artifactId>guava</artifactId>
</dependency>
+ <dependency>
+ <groupId>it.unimi.dsi</groupId>
+ <artifactId>fastutil</artifactId>
+ </dependency>
</dependencies>
</project>
diff --git a/hyracks-fullstack/hyracks/hyracks-util/src/main/java/org/apache/hyracks/util/fastutil/Collectors.java b/hyracks-fullstack/hyracks/hyracks-util/src/main/java/org/apache/hyracks/util/fastutil/Collectors.java
new file mode 100644
index 0000000..b15154b
--- /dev/null
+++ b/hyracks-fullstack/hyracks/hyracks-util/src/main/java/org/apache/hyracks/util/fastutil/Collectors.java
@@ -0,0 +1,131 @@
+/*
+ * 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.hyracks.util.fastutil;
+
+import java.util.Collections;
+import java.util.Objects;
+import java.util.Set;
+import java.util.function.BiConsumer;
+import java.util.function.BinaryOperator;
+import java.util.function.Function;
+import java.util.function.Supplier;
+import java.util.stream.Collector;
+import java.util.stream.Collector.Characteristics;
+
+import it.unimi.dsi.fastutil.ints.Int2ObjectMap;
+import it.unimi.dsi.fastutil.ints.Int2ObjectOpenHashMap;
+import it.unimi.dsi.fastutil.longs.Long2ObjectMap;
+import it.unimi.dsi.fastutil.longs.Long2ObjectOpenHashMap;
+
+public class Collectors {
+
+ private static final Set<Characteristics> IDENTITY_CHARACTERISTICS =
+ Collections.singleton(Characteristics.IDENTITY_FINISH);
+
+ private Collectors() {
+ throw new AssertionError("do not instantiate");
+ }
+
+ public static <T> Collector<Int2ObjectMap.Entry<T>, Int2ObjectMap<T>, Int2ObjectMap<T>> toInt2ObjectMap() {
+ return new Collector<Int2ObjectMap.Entry<T>, Int2ObjectMap<T>, Int2ObjectMap<T>>() {
+ @Override
+ public Supplier<Int2ObjectMap<T>> supplier() {
+ return Int2ObjectOpenHashMap::new;
+ }
+
+ @Override
+ public BiConsumer<Int2ObjectMap<T>, Int2ObjectMap.Entry<T>> accumulator() {
+ return (map, element) -> {
+ int key = element.getIntKey();
+ T value = Objects.requireNonNull(element.getValue());
+ T oldValue = map.putIfAbsent(key, value);
+ if (oldValue != null)
+ throw duplicateKey(key, oldValue, value);
+ };
+ }
+
+ @Override
+ public BinaryOperator<Int2ObjectMap<T>> combiner() {
+ return (map1, map2) -> {
+ for (Int2ObjectMap.Entry<T> e : map2.int2ObjectEntrySet()) {
+ accumulator().accept(map1, e);
+ }
+ return map1;
+ };
+ }
+
+ @Override
+ public Function<Int2ObjectMap<T>, Int2ObjectMap<T>> finisher() {
+ return Function.identity();
+ }
+
+ @Override
+ public Set<Characteristics> characteristics() {
+ return IDENTITY_CHARACTERISTICS;
+ }
+
+ };
+ }
+
+ public static <T> Collector<Long2ObjectMap.Entry<T>, Long2ObjectMap<T>, Long2ObjectMap<T>> toLong2ObjectMap() {
+ return new Collector<Long2ObjectMap.Entry<T>, Long2ObjectMap<T>, Long2ObjectMap<T>>() {
+ @Override
+ public Supplier<Long2ObjectMap<T>> supplier() {
+ return Long2ObjectOpenHashMap::new;
+ }
+
+ @Override
+ public BiConsumer<Long2ObjectMap<T>, Long2ObjectMap.Entry<T>> accumulator() {
+ return (map, element) -> {
+ long key = element.getLongKey();
+ T value = Objects.requireNonNull(element.getValue());
+ T oldValue = map.putIfAbsent(key, value);
+ if (oldValue != null)
+ throw duplicateKey(key, oldValue, value);
+ };
+ }
+
+ @Override
+ public BinaryOperator<Long2ObjectMap<T>> combiner() {
+ return (map1, map2) -> {
+ for (Long2ObjectMap.Entry<T> e : map2.long2ObjectEntrySet()) {
+ accumulator().accept(map1, e);
+ }
+ return map1;
+ };
+ }
+
+ @Override
+ public Function<Long2ObjectMap<T>, Long2ObjectMap<T>> finisher() {
+ return Function.identity();
+ }
+
+ @Override
+ public Set<Characteristics> characteristics() {
+ return IDENTITY_CHARACTERISTICS;
+ }
+
+ };
+ }
+
+ private static IllegalStateException duplicateKey(Object key, Object oldValue, Object newValue) {
+ return new IllegalStateException("Duplicate key " + key + " (old: " + oldValue + ", new: " + newValue + ")");
+ }
+
+}