Added Java implementation

Added Java implementation

Author: sergfrolov

Diff for: .gitignore

@@ -1,3 +1,7 @@
 node_modules
 *.log
 .DS_Store
+# IntelliJ
+/out/
+/.idea
+*.iml

Diff for: Java/src/1-closure.java

@@ -0,0 +1,19 @@
+import java.util.function.*;
+
+class Closure {
+
+    public static void main(String[] args)  {
+        Function<Double,Function<Double,Double>> createLog = (Double base) -> (Double n) -> log(base, n);
+        Function<Double,Double> lg = createLog.apply(10d);
+        Function<Double,Double> ln = createLog.apply(Math.E);
+        //usage
+        System.out.println(lg.apply(1000d));
+        System.out.println(ln.apply(Math.E * Math.E));
+    }
+
+    private static Double log(Double base, Double n)
+    {
+        return Math.log(n)/ Math.log(base);
+    }
+
+}

Diff for: Java/src/2-lambda.java

@@ -0,0 +1,16 @@
+import java.util.function.Function;
+
+class Lambda {
+    public static void main(String[] args) {
+        Function<Double,Double> lg = (Double n) -> log(10d, n);
+        Function<Double,Double> ln = (Double n) -> log(Math.E, n);
+        //usage
+        System.out.println(lg.apply(1000d));
+        System.out.println(ln.apply(Math.E*Math.E));
+    }
+
+    private static Double log(Double base, Double n)
+    {
+        return Math.log(n)/ Math.log(base);
+    }
+}

Diff for: Java/src/4-curry.java

@@ -0,0 +1,29 @@
+import java.util.function.Function;
+
+class Curry {
+    public static void main(String[] args) {
+        final TriFunction<Integer,Integer,Integer,Integer> add = Curry::sum;
+        Function<Integer, Function<Integer, Function<Integer,Integer>>> uncurry = Curry.curry(add);
+        TriFunction<Integer,Integer,Integer,Integer> curry = Curry.uncurry(uncurry);
+        //usage
+        System.out.println("Curried result : " + curry.apply(1,2,3));
+        System.out.println("Uncurried result : " + uncurry.apply(1).apply(2).apply(3));
+    }
+    private static Integer sum(Integer a, Integer b, Integer c){
+        return a + b + c;
+    }
+
+    private static <A, B, C, D> Function<A, Function<B, Function<C,D>>> curry(final TriFunction<A, B, C, D> f) {
+        return (A a) -> (B b) -> (C c) -> f.apply(a, b, c);
+    }
+
+    private static <A, B, C, D> TriFunction<A,B,C,D> uncurry(Function<A, Function<B, Function<C, D>>> f) {
+        return (A a, B b, C c) -> f.apply(a).apply(b).apply(c);
+    }
+
+    @FunctionalInterface
+    public interface TriFunction<A,B,C,D>{
+        D apply(A a,B b,C c);
+    }
+
+}