BAEL-1078 How to iterate over a stream with indices (eugenp#2544)

fatosmorina · Eugen · commit 94d02ed1f6c9 · 2017-09-02T11:42:24.000+03:00
* Add the example with EntryStream

* Add the example with EntryStream

* Add vavr

* Implement the method getOddIndexedStringsVersionTwo

* Implement the method givenArray_whenGetIndexedStrings_thenReturnListOfOddStringsVersionTwo

* BAEL-1078 Code formatting

* Extract tuples using map

* Fix merge conflicts
diff --git a/core-java/src/main/java/com/baeldung/stream/StreamIndices.java b/core-java/src/main/java/com/baeldung/stream/StreamIndices.java
@@ -1,72 +1,62 @@
 package com.baeldung.stream;
 
-import java.util.ArrayList;
 import java.util.List;
 import java.util.stream.Collectors;
 import java.util.stream.IntStream;
 
 import com.codepoetics.protonpack.Indexed;
 import com.codepoetics.protonpack.StreamUtils;
 
-import io.vavr.Tuple2;
 import io.vavr.collection.Stream;
 import one.util.streamex.EntryStream;
 
 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());
+        List<String> evenIndexedNames = IntStream.range(0, names.length)
+            .filter(i -> i % 2 == 0)
+            .mapToObj(i -> names[i])
+            .collect(Collectors.toList());
         return evenIndexedNames;
     }
 
     public List<String> getEvenIndexedStringsVersionTwo(List<String> names) {
-        List<String> evenIndexedNames = EntryStream
-          .of(names)
-          .filterKeyValue((index, name) -> index % 2 == 0)
-          .values()
-          .toList();
+        List<String> evenIndexedNames = EntryStream.of(names)
+            .filterKeyValue((index, name) -> index % 2 == 0)
+            .values()
+            .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());
+        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());
+        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());
+        List<String> oddIndexedNames = IntStream.range(0, names.length)
+            .filter(i -> i % 2 == 1)
+            .mapToObj(i -> names[i])
+            .collect(Collectors.toList());
         return oddIndexedNames;
     }
 
     public static List<String> getOddIndexedStringsVersionTwo(String[] names) {
-        List<Tuple2<String, Integer>> tuples = Stream
-          .of(names)
-          .zipWithIndex()
-          .filter(tuple -> tuple._2 % 2 == 1)
-          .toJavaList();
-        List<String> oddIndexedNames = new ArrayList<String>();
-        tuples.forEach(tuple -> {
-            oddIndexedNames.add(tuple._1);
-        });
+        List<String> oddIndexedNames = Stream.of(names)
+            .zipWithIndex()
+            .filter(tuple -> tuple._2 % 2 == 1)
+            .map(tuple -> tuple._1)
+            .toJavaList();
         return oddIndexedNames;
     }
+
 }
