1 files changed, 142 insertions, 0 deletions
diff --git a/common-app-api/src/test/java/org/openecomp/sdc/common/util/StreamUtilsTests.java b/common-app-api/src/test/java/org/openecomp/sdc/common/util/StreamUtilsTests.java
new file mode 100644
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+++ b/common-app-api/src/test/java/org/openecomp/sdc/common/util/StreamUtilsTests.java
@@ -0,0 +1,142 @@
+/*-
+ * ============LICENSE_START=======================================================
+ * SDC
+ * ================================================================================
+ * Copyright (C) 2017 AT&T Intellectual Property. All rights reserved.
+ * ================================================================================
+ * Licensed 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.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.openecomp.sdc.common.util;
+
+import fj.data.Either;
+import static org.junit.Assert.assertEquals;
+import org.junit.Test;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+import java.util.function.Function;
+import java.util.stream.Collectors;
+import java.util.stream.Stream;
+
+import static org.junit.Assert.assertTrue;
+
+public class StreamUtilsTests {
+	@Test
+	public void testTakeWhilePredicateNotMet() {
+		List<Either<Integer, Boolean>> list = buildListWith10Integers();
+
+        assertEquals(10, StreamUtils.takeWhile(list.stream(), Either::isLeft).count());
+	}
+
+	@Test
+	public void testTakeWhilePredicateIsMet() {
+		List<Either<Integer, Boolean>> list = buildListWith10Integers();
+		addToBooleansToList(list);
+
+		final Stream<Either<Integer, Boolean>> takeWhileStream = StreamUtils.takeWhile(list.stream(), Either::isLeft);
+        assertEquals(0, takeWhileStream.filter(Either::isRight).count());
+	}
+
+	@Test
+	public <T> void testTakeErrorEvalOnlyOnce() {
+		List<Integer> bucket = new ArrayList<>();
+		// API
+		Function<Integer, Either<Integer, Boolean>> cons = num -> {
+			Either<Integer, Boolean> ret;
+			bucket.add(num);
+			if (num > 5) {
+				ret = Either.right(false);
+			} else {
+				ret = Either.left(num);
+			}
+			;
+			return ret;
+		};
+
+		List<Integer> num1to10 = Arrays.asList(1, 2, 3, 4, 5, 6, 7, 8, 9, 10);
+		Stream<Either<Integer, Boolean>> streamEithers = num1to10.stream().map(cons::apply);
+		List<Either<Integer, Boolean>> collect = StreamUtils.takeWhilePlusOneNoEval(streamEithers, Either::isLeft)
+				.collect(Collectors.toList());
+		assertTrue(bucket.size() <= 6);
+		assertTrue(collect.size() <= 6);
+        assertEquals(1, collect.stream().filter(Either::isRight).count());
+
+	}
+
+	@Test
+	public void testTakeWhilePlusOnePredicateNotMet() {
+		List<Either<Integer, Boolean>> list = buildListWith10Integers();
+
+        assertEquals(10, StreamUtils.takeWhilePlusOne(list.stream(), Either::isLeft).count());
+	}
+
+	@Test
+	public void testTakeWhilePlusOnePredicateIsMet() {
+		List<Either<Integer, Boolean>> list = buildListWith10Integers();
+		addToBooleansToList(list);
+
+		final Stream<Either<Integer, Boolean>> takeWhilePlusOneStream = StreamUtils.takeWhilePlusOne(list.stream(),
+                Either::isLeft);
+        assertEquals(1, takeWhilePlusOneStream.filter(Either::isRight).count());
+	}
+
+	private void addToBooleansToList(List<Either<Integer, Boolean>> list) {
+		list.add(Either.right(false));
+		list.add(Either.right(false));
+	}
+
+	private List<Either<Integer, Boolean>> buildListWith10Integers() {
+		List<Either<Integer, Boolean>> list = new ArrayList<>();
+		for (int i = 0; i < 10; i++) {
+			list.add(Either.left(i));
+		}
+		return list;
+	}
+
+	@Test
+	public void myTest() {
+		List<Integer> list = new ArrayList<>();
+		for (int i = 0; i < 10; i++) {
+			list.add(i);
+		}
+
+		List<Either<Integer, Boolean>> container = new ArrayList<>();
+		list.stream().map(e -> myBusinessLogic(e, container)).filter(Either::isRight).findAny();
+		// Actual Results are in container
+        assertEquals(6, container.size());
+
+	}
+
+	private Either<Integer, Boolean> myBusinessLogic(int e, List<Either<Integer, Boolean>> cobtainerList) {
+		Either<Integer, Boolean> eitherElement = similuteDBAccess(e);
+		// Keep The results in external List
+		cobtainerList.add(eitherElement);
+
+		return eitherElement;
+	}
+
+	private Either<Integer, Boolean> similuteDBAccess(int e) {
+		Either<Integer, Boolean> eitherElement;
+		if (e < 5) {
+			// DB Success
+			eitherElement = Either.left(e);
+		} else {
+			// DB Fail
+			eitherElement = Either.right(true);
+		}
+		return eitherElement;
+	}
+}