BAEL-669 test of an infinite stream (#1126)

* BAEL-669 test of an infinite stream

* BAEL-699 example of custom type infinite stream

* BAEL-699 do..while stream way

* BAEL-669 generate stream of random uuids

core-java/src/main/java/com/baeldung/stream/InfiniteStreams.java

@@ -0,0 +1,27 @@
+package com.baeldung.stream;
+
+
+import java.util.stream.Stream;
+
+public class InfiniteStreams {
+    public static void main(String[] args) {
+        doWhileOldWay();
+
+        doWhileStreamWay();
+
+    }
+
+    private static void doWhileOldWay() {
+
+        int i = 0;
+        while (i < 10) {
+            System.out.println(i);
+            i++;
+        }
+    }
+
+    private static void doWhileStreamWay() {
+        Stream<Integer> integers = Stream.iterate(0, i -> i + 1);
+        integers.limit(10).forEach(System.out::println);
+    }
+}

core-java/src/test/java/com/baeldung/stream/InfiniteStreamTest.java

@@ -0,0 +1,48 @@
+package com.baeldung.stream;
+
+
+import org.junit.Test;
+
+import java.util.Arrays;
+import java.util.List;
+import java.util.Random;
+import java.util.UUID;
+import java.util.function.Supplier;
+import java.util.stream.Collectors;
+import java.util.stream.Stream;
+
+import static org.junit.Assert.assertEquals;
+
+public class InfiniteStreamTest {
+
+    @Test
+    public void givenInfiniteStream_whenUseIntermediateLimitMethod_thenShouldTerminateInFiniteTime() {
+        //given
+        Stream<Integer> infiniteStream = Stream.iterate(0, i -> i + 2);
+
+        //when
+        List<Integer> collect = infiniteStream
+                .limit(10)
+                .collect(Collectors.toList());
+
+        //then
+        assertEquals(collect, Arrays.asList(0, 2, 4, 6, 8, 10, 12, 14, 16, 18));
+    }
+
+    @Test
+    public void givenInfiniteStreamOfRandomInts_whenUseLimit_shouldTerminateInFiniteTime() {
+        //given
+        Supplier<UUID> randomUUIDSupplier = UUID::randomUUID;
+        Stream<UUID> infiniteStreamOfRandomUUID = Stream.generate(randomUUIDSupplier);
+
+        //when
+        List<UUID> randomInts = infiniteStreamOfRandomUUID
+                .skip(10)
+                .limit(10)
+                .collect(Collectors.toList());
+
+        //then
+        assertEquals(randomInts.size(), 10);
+    }
+
+}