arrays lambda example

pdvlp · pdvlp · commit ee0cefda3fc2 · 2015-07-31T02:33:06.000+08:00
diff --git a/src/main/java/com/winterbe/java8/samples/lambda/ArraysLambda.java b/src/main/java/com/winterbe/java8/samples/lambda/ArraysLambda.java
@@ -0,0 +1,59 @@
+package com.winterbe.java8.samples.lambda;
+
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.Comparator;
+import java.util.List;
+import java.util.Optional;
+
+/**
+ * @author Benjamin Winterberg
+ */
+public class ArraysLambda {
+
+    public static void main(String[] args) {
+        List<String> names = Arrays.asList("peter", "anna", "mike", "xenia");
+
+        usualSort(names);
+        lambda1Sort(names);
+		lambda2Sort(names);
+        lambda3Sort(names);
+        System.out.println(names);
+
+        names.sort(Collections.reverseOrder());
+        System.out.println(names);
+
+        List<String> names2 = Arrays.asList("peter", null, "anna", "mike", "xenia");
+        names2.sort(Comparator.nullsLast(String::compareTo));
+        System.out.println(names2);
+
+        
+        List<String> names3 = null;
+        Optional.ofNullable(names3).ifPresent(list -> list.sort(Comparator.naturalOrder()));
+        System.out.println(names3);
+    }
+
+	private static void lambda3Sort(List<String> names) {
+		Collections.sort(names, (a, b) -> b.compareTo(a));
+	}
+
+	private static void lambda2Sort(List<String> names) {
+		Collections.sort(names, (String a, String b) -> b.compareTo(a));
+	}
+
+	private static void lambda1Sort(List<String> names) {
+		Collections.sort(names, (String a, String b) -> {
+            return b.compareTo(a);
+        });
+	}
+
+	private static void usualSort(List<String> names) {
+		Collections.sort(names, new Comparator<String>() {
+            @Override
+            public int compare(String a, String b) {
+                return b.compareTo(a);
+            }
+        });
+	}
+
+}
