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authorHarald Musum <musum@verizonmedia.com>2020-07-17 12:04:07 +0200
committerGitHub <noreply@github.com>2020-07-17 12:04:07 +0200
commit1c69b4e72b3212e3ce989a8675db08ac51b7f79d (patch)
tree3714c4ea91a3e68826e5ddbb73f71daa93105aec /vespajlib
parent174910488e7793d9962775c0325764ed265ea2ce (diff)
Revert "Load platform bundles separately 3"
Diffstat (limited to 'vespajlib')
-rw-r--r--vespajlib/src/main/java/com/yahoo/collections/PredicateSplit.java40
-rw-r--r--vespajlib/src/test/java/com/yahoo/collections/PredicateSplitTestCase.java30
2 files changed, 70 insertions, 0 deletions
diff --git a/vespajlib/src/main/java/com/yahoo/collections/PredicateSplit.java b/vespajlib/src/main/java/com/yahoo/collections/PredicateSplit.java
new file mode 100644
index 00000000000..1b3941df7bf
--- /dev/null
+++ b/vespajlib/src/main/java/com/yahoo/collections/PredicateSplit.java
@@ -0,0 +1,40 @@
+// Copyright 2017 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.collections;
+
+import java.util.List;
+import java.util.ArrayList;
+import java.util.function.Predicate;
+
+/**
+ * Class holding the result of a partition-by-predicate operation.
+ **/
+public class PredicateSplit<E> {
+ public final List<E> falseValues; /// list of values where the predicate returned false
+ public final List<E> trueValues; /// list of values where the predicate returned true
+
+ private PredicateSplit() {
+ falseValues = new ArrayList<E>();
+ trueValues = new ArrayList<E>();
+ }
+
+ /**
+ * Perform a partition-by-predicate operation.
+ * Each value in the input is tested by the predicate and
+ * added to either the falseValues list or the trueValues list.
+ * @param collection The input collection.
+ * @param predicate A test for selecting the target list.
+ * @return Two lists bundled in an object.
+ **/
+ public static <V> PredicateSplit<V> partition(Iterable<V> collection, Predicate<? super V> predicate)
+ {
+ PredicateSplit<V> r = new PredicateSplit<V>();
+ for (V value : collection) {
+ if (predicate.test(value)) {
+ r.trueValues.add(value);
+ } else {
+ r.falseValues.add(value);
+ }
+ }
+ return r;
+ }
+}
diff --git a/vespajlib/src/test/java/com/yahoo/collections/PredicateSplitTestCase.java b/vespajlib/src/test/java/com/yahoo/collections/PredicateSplitTestCase.java
new file mode 100644
index 00000000000..05a719d6a4d
--- /dev/null
+++ b/vespajlib/src/test/java/com/yahoo/collections/PredicateSplitTestCase.java
@@ -0,0 +1,30 @@
+// Copyright 2017 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.collections;
+
+import org.junit.Test;
+
+import java.util.List;
+import java.util.ArrayList;
+
+import static org.junit.Assert.assertEquals;
+
+public class PredicateSplitTestCase {
+ @Test
+ public void requireThatSplitWorks() {
+ List<Integer> l = new ArrayList<Integer>();
+ l.add(1);
+ l.add(6);
+ l.add(2);
+ l.add(4);
+ l.add(5);
+ PredicateSplit<Integer> result = PredicateSplit.partition(l, x -> (x % 2 == 0));
+ assertEquals((long) result.falseValues.size(), 2L);
+ assertEquals((long) result.falseValues.get(0), 1L);
+ assertEquals((long) result.falseValues.get(1), 5L);
+
+ assertEquals((long) result.trueValues.size(), 3L);
+ assertEquals((long) result.trueValues.get(0), 6L);
+ assertEquals((long) result.trueValues.get(1), 2L);
+ assertEquals((long) result.trueValues.get(2), 4L);
+ }
+}