adding spliterator

java-8/spliterator/StudentSpliterator.java

@@ -0,0 +1,67 @@
+package data;
+
+import java.util.List;
+import java.util.Spliterator;
+import java.util.function.Consumer;
+
+public class StudentSpliterator implements Spliterator<Student> {
+    private final List<Student> studentList;
+
+    private int endIndex;
+    private int startIndex;
+
+    public StudentSpliterator(List<Student> studentList) {
+        this(studentList, 0, studentList.size());
+    }
+
+    private StudentSpliterator(List<Student> studentList, int startIndex, int endIndex) {
+        this.studentList = studentList;
+        this.startIndex = startIndex;
+        this.endIndex = endIndex;
+    }
+
+    @Override
+    public boolean tryAdvance(Consumer<? super Student> action) {
+        if (getSize() > 0) {
+            action.accept(studentList.get(startIndex));
+            startIndex++;
+            return true;
+        }
+        return false;
+    }
+
+    @Override
+    public Spliterator<Student> trySplit() {
+
+        if (getSize() == 1) {
+            return null;
+        }
+
+        int newStartIndex;
+        int newEndIndex = endIndex;
+
+        if (getSize() % 2 == 0) {
+            newStartIndex = startIndex + getSize() / 2;
+            this.endIndex -= getSize() / 2;
+        } else {
+            newStartIndex = startIndex + getSize() / 2 + 1;
+            this.endIndex -= getSize() / 2;
+        }
+        return new StudentSpliterator(studentList, newStartIndex, newEndIndex);
+    }
+
+
+    private int getSize() {
+        return endIndex - startIndex;
+    }
+
+    @Override
+    public long estimateSize() {
+        return studentList.size();
+    }
+
+    @Override
+    public int characteristics() {
+        return NONNULL;
+    }
+}