play with method references and lambdas

.gitignore

@@ -1,4 +1,5 @@
 *.class
+*.iml
 
 # Mobile Tools for Java (J2ME)
 .mtj.tmp/

src/main/java/hochraldo/LambaMethodReference.java

@@ -0,0 +1,37 @@
+package hochraldo;
+
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Objects;
+import java.util.function.Function;
+import java.util.function.Predicate;
+import java.util.function.Supplier;
+
+public class LambaMethodReference {
+
+
+    public static void main(String... args) {
+
+        // static method reference
+        Predicate<Object> nullCheck = Objects::nonNull;
+        System.out.println(nullCheck.test(null));
+        System.out.println(nullCheck.test(new Object()));
+
+        // constructor reference
+        Supplier<List<Integer>> listSupplier = ArrayList::new;
+        List<Integer> list1 = listSupplier.get();
+        list1.add(1);
+        System.out.println(list1);
+        List<Integer> list2 = listSupplier.get();
+        list2.add(2);
+        list2.add(3);
+        System.out.println(list2);
+
+        // method reference
+        String s = "Foo";
+        Function<Integer, Character> charAt = s::charAt;
+        System.out.println(charAt.apply(0));
+    }
+}
+