BAEL-1078 Stream Indices - Update pom.xml (eugenp#2516)

* Update pom.xml * BAEL-1078 Stream indices
swasb123 · Aug 29, 2017 · b3a291a · b3a291a
1 parent 8da9bee
commit b3a291a
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diff --git a/core-java/pom.xml b/core-java/pom.xml
@@ -196,6 +196,16 @@
             <artifactId>hirondelle-date4j</artifactId>
             <version>${hirondelle-date4j.version}</version>
         </dependency>
+        <dependency>
+            <groupId>com.codepoetics</groupId>
+            <artifactId>protonpack</artifactId>
+            <version>${protonpack.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>one.util</groupId>
+            <artifactId>streamex</artifactId>
+            <version>${streamex.version}</version>
+        </dependency>
     </dependencies>
 
     <build>
@@ -420,6 +430,8 @@
         <fscontext.version>4.6-b01</fscontext.version>
         <joda-time.version>2.9.9</joda-time.version>
         <hirondelle-date4j.version>1.5.1</hirondelle-date4j.version>
+        <protonpack.version>1.13</protonpack.version>
+        <streamex.version>0.6.5</streamex.version>
 
         <!-- testing -->
         <org.hamcrest.version>1.3</org.hamcrest.version>

diff --git a/core-java/src/main/java/com/baeldung/stream/StreamIndices.java b/core-java/src/main/java/com/baeldung/stream/StreamIndices.java
@@ -0,0 +1,37 @@
+package com.baeldung.stream;
+
+import java.util.List;
+import java.util.stream.Collectors;
+import java.util.stream.IntStream;
+
+import com.codepoetics.protonpack.Indexed;
+import com.codepoetics.protonpack.StreamUtils;
+
+public class StreamIndices {
+
+    public static List<String> getEvenIndexedStrings(String[] names) {
+        List<String> evenIndexedNames = IntStream.range(0, names.length)
+          .filter(i -> i % 2 == 0).mapToObj(i -> names[i])
+          .collect(Collectors.toList());
+        return evenIndexedNames;
+    }
+
+    public static List<Indexed<String>> getEvenIndexedStrings(List<String> names) {
+        List<Indexed<String>> list = StreamUtils.zipWithIndex(names.stream())
+          .filter(i -> i.getIndex() % 2 == 0).collect(Collectors.toList());
+        return list;
+    }
+
+    public static List<Indexed<String>> getOddIndexedStrings(List<String> names) {
+        List<Indexed<String>> list = StreamUtils.zipWithIndex(names.stream())
+          .filter(i -> i.getIndex() % 2 == 1).collect(Collectors.toList());
+        return list;
+    }
+
+    public static List<String> getOddIndexedStrings(String[] names) {
+        List<String> oddIndexedNames = IntStream.range(0, names.length)
+          .filter(i -> i % 2 == 1).mapToObj(i -> names[i])
+          .collect(Collectors.toList());
+        return oddIndexedNames;
+    }
+}
diff --git a/core-java/src/test/java/com/baeldung/stream/StreamIndicesTest.java b/core-java/src/test/java/com/baeldung/stream/StreamIndicesTest.java
@@ -0,0 +1,50 @@
+package com.baeldung.stream;
+
+import static org.junit.Assert.assertEquals;
+
+import java.util.Arrays;
+import java.util.List;
+
+import org.junit.Test;
+
+import com.codepoetics.protonpack.Indexed;
+
+public class StreamIndicesTest {
+
+    @Test
+    public void givenArray_whenGetIndexedStrings_thenReturnListOfEvenIndexedStrings() {
+        String[] names = { "Afrim", "Bashkim", "Besim", "Lulzim", "Durim", "Shpetim" };
+        List<String> expectedResult = Arrays.asList("Afrim", "Besim", "Durim");
+        List<String> actualResult = StreamIndices.getEvenIndexedStrings(names);
+
+        assertEquals(expectedResult, actualResult);
+    }
+
+    @Test
+    public void givenArray_whenGetIndexedStrings_thenReturnListOfOddStrings() {
+        String[] names = { "Afrim", "Bashkim", "Besim", "Lulzim", "Durim", "Shpetim" };
+        List<String> expectedResult = Arrays.asList("Bashkim", "Lulzim", "Shpetim");
+        List<String> actualResult = StreamIndices.getOddIndexedStrings(names);
+
+        assertEquals(expectedResult, actualResult);
+    }
+
+    @Test
+    public void givenList_whenGetIndexedStrings_thenReturnListOfEvenIndexedStrings() {
+        List<String> names = Arrays.asList("Afrim", "Bashkim", "Besim", "Lulzim", "Durim", "Shpetim");
+        List<Indexed<String>> expectedResult = Arrays.asList(Indexed.index(0, "Afrim"), Indexed.index(2, "Besim"), Indexed.index(4, "Durim"));
+        List<Indexed<String>> actualResult = StreamIndices.getEvenIndexedStrings(names);
+
+        assertEquals(expectedResult, actualResult);
+    }
+
+    @Test
+    public void givenList_whenGetIndexedStrings_thenReturnListOfOddIndexedStrings() {
+        List<String> names = Arrays.asList("Afrim", "Bashkim", "Besim", "Lulzim", "Durim", "Shpetim");
+        List<Indexed<String>> expectedResult = Arrays.asList(Indexed.index(1, "Bashkim"), Indexed.index(3, "Lulzim"), Indexed.index(5, "Shpetim"));
+        List<Indexed<String>> actualResult = StreamIndices.getOddIndexedStrings(names);
+
+        assertEquals(expectedResult, actualResult);
+    }
+
+}