From 438ff48c275d1d1dd92bbf3e210b300b422c19d7 Mon Sep 17 00:00:00 2001 From: cror Date: Wed, 16 Jan 2019 17:09:44 +0100 Subject: [PATCH 1/3] BAEL-2546: added Stream.count examples --- .../stream/filter/StreamCountUnitTest.java | 72 +++++++++++++++++++ 1 file changed, 72 insertions(+) create mode 100644 java-streams/src/test/java/com/baeldung/stream/filter/StreamCountUnitTest.java diff --git a/java-streams/src/test/java/com/baeldung/stream/filter/StreamCountUnitTest.java b/java-streams/src/test/java/com/baeldung/stream/filter/StreamCountUnitTest.java new file mode 100644 index 0000000000..1cad710e14 --- /dev/null +++ b/java-streams/src/test/java/com/baeldung/stream/filter/StreamCountUnitTest.java @@ -0,0 +1,72 @@ +package com.baeldung.stream.filter; + +import org.junit.Test; +import org.junit.Before; + +import java.util.Arrays; +import java.util.List; + +import static org.assertj.core.api.Assertions.assertThat; + +public class StreamCountUnitTest { + + private List customers; + + @Before + public void setUp() { + Customer john = new Customer("John P.", 15, "https://images.unsplash.com/photo-1543320485-d0d5a49c2b2e"); + Customer sarah = new Customer("Sarah M.", 200); + Customer charles = new Customer("Charles B.", 150); + Customer mary = new Customer("Mary T.", 1, "https://images.unsplash.com/photo-1543297057-25167dfc180e"); + customers = Arrays.asList(john, sarah, charles, mary); + } + + @Test + public void givenListOfCustomers_whenCount_thenGetListSize() { + long count = customers + .stream() + .count(); + + assertThat(count).isEqualTo(4L); + } + + @Test + public void givenListOfCustomers_whenFilterByPointsOver100AndCount_thenGetTwo() { + long countBigCustomers = customers + .stream() + .filter(c -> c.getPoints() > 100) + .count(); + + assertThat(countBigCustomers).isEqualTo(2L); + } + + @Test + public void givenListOfCustomers_whenFilterByPointsAndNameAndCount_thenGetOne() { + long count = customers + .stream() + .filter(c -> c.getPoints() > 10 && c.getName().startsWith("Charles")) + .count(); + + assertThat(count).isEqualTo(1L); + } + + @Test + public void givenListOfCustomers_whenNoneMatchesFilterAndCount_thenGetZero() { + long count = customers + .stream() + .filter(c -> c.getPoints() > 500) + .count(); + + assertThat(count).isEqualTo(0L); + } + + @Test + public void givenListOfCustomers_whenUsingMethodOverHundredPointsAndCount_thenGetTwo() { + long count = customers + .stream() + .filter(Customer::hasOverThousandPoints) + .count(); + + assertThat(count).isEqualTo(2L); + } +} From 2b7e66a3989bebd92e76d4d116f74b72db2edcc4 Mon Sep 17 00:00:00 2001 From: cror Date: Wed, 16 Jan 2019 17:14:35 +0100 Subject: [PATCH 2/3] renaming method according to content: thousand -> hundred --- .../src/main/java/com/baeldung/stream/filter/Customer.java | 2 +- .../java/com/baeldung/stream/filter/StreamCountUnitTest.java | 2 +- .../java/com/baeldung/stream/filter/StreamFilterUnitTest.java | 4 ++-- 3 files changed, 4 insertions(+), 4 deletions(-) diff --git a/java-streams/src/main/java/com/baeldung/stream/filter/Customer.java b/java-streams/src/main/java/com/baeldung/stream/filter/Customer.java index 49da6e7175..fd4f6021ff 100644 --- a/java-streams/src/main/java/com/baeldung/stream/filter/Customer.java +++ b/java-streams/src/main/java/com/baeldung/stream/filter/Customer.java @@ -32,7 +32,7 @@ public class Customer { return this.points > points; } - public boolean hasOverThousandPoints() { + public boolean hasOverHundredPoints() { return this.points > 100; } diff --git a/java-streams/src/test/java/com/baeldung/stream/filter/StreamCountUnitTest.java b/java-streams/src/test/java/com/baeldung/stream/filter/StreamCountUnitTest.java index 1cad710e14..742e5aedc9 100644 --- a/java-streams/src/test/java/com/baeldung/stream/filter/StreamCountUnitTest.java +++ b/java-streams/src/test/java/com/baeldung/stream/filter/StreamCountUnitTest.java @@ -64,7 +64,7 @@ public class StreamCountUnitTest { public void givenListOfCustomers_whenUsingMethodOverHundredPointsAndCount_thenGetTwo() { long count = customers .stream() - .filter(Customer::hasOverThousandPoints) + .filter(Customer::hasOverHundredPoints) .count(); assertThat(count).isEqualTo(2L); diff --git a/java-streams/src/test/java/com/baeldung/stream/filter/StreamFilterUnitTest.java b/java-streams/src/test/java/com/baeldung/stream/filter/StreamFilterUnitTest.java index cf82802940..29190f7298 100644 --- a/java-streams/src/test/java/com/baeldung/stream/filter/StreamFilterUnitTest.java +++ b/java-streams/src/test/java/com/baeldung/stream/filter/StreamFilterUnitTest.java @@ -62,7 +62,7 @@ public class StreamFilterUnitTest { List customersWithMoreThan100Points = customers .stream() - .filter(Customer::hasOverThousandPoints) + .filter(Customer::hasOverHundredPoints) .collect(Collectors.toList()); assertThat(customersWithMoreThan100Points).hasSize(2); @@ -81,7 +81,7 @@ public class StreamFilterUnitTest { .flatMap(c -> c .map(Stream::of) .orElseGet(Stream::empty)) - .filter(Customer::hasOverThousandPoints) + .filter(Customer::hasOverHundredPoints) .collect(Collectors.toList()); assertThat(customersWithMoreThan100Points).hasSize(2); From 735b0a10b28a9868baeab71807e6ff5ab7e57119 Mon Sep 17 00:00:00 2001 From: Loredana Crusoveanu Date: Thu, 17 Jan 2019 23:25:26 +0200 Subject: [PATCH 3/3] Update StreamFilterUnitTest.java --- .../java/com/baeldung/stream/filter/StreamFilterUnitTest.java | 1 + 1 file changed, 1 insertion(+) diff --git a/java-streams/src/test/java/com/baeldung/stream/filter/StreamFilterUnitTest.java b/java-streams/src/test/java/com/baeldung/stream/filter/StreamFilterUnitTest.java index 29190f7298..5ad875f61e 100644 --- a/java-streams/src/test/java/com/baeldung/stream/filter/StreamFilterUnitTest.java +++ b/java-streams/src/test/java/com/baeldung/stream/filter/StreamFilterUnitTest.java @@ -156,4 +156,5 @@ public class StreamFilterUnitTest { }) .collect(Collectors.toList())).isInstanceOf(RuntimeException.class); } + }