HOMEWORK bobocode-projects#7 – FUNCTIONAL PROGRAMMING

- p2

Author: Andrii Bobrov

5-0-functional-programming/5-1-1-crazy-lambdas/src/main/java/com/bobocode/fp/CrazyLambdas.java

@@ -4,6 +4,7 @@
 
 import java.math.BigDecimal;
 import java.util.Map;
+import java.util.concurrent.ThreadLocalRandom;
 import java.util.function.*;
 
 /**
@@ -21,7 +22,7 @@ public class CrazyLambdas {
      * @return a string supplier
      */
     public static Supplier<String> helloSupplier() {
-        throw new ExerciseNotCompletedException();
+        return () -> "Hello";
     }
 
     /**
@@ -30,7 +31,7 @@ public static Supplier<String> helloSupplier() {
      * @return a string predicate
      */
     public static Predicate<String> isEmptyPredicate() {
-        throw new ExerciseNotCompletedException();
+        return String::isEmpty;
     }
 
     /**
@@ -40,7 +41,7 @@ public static Predicate<String> isEmptyPredicate() {
      * @return function that repeats Strings
      */
     public static BiFunction<String, Integer, String> stringMultiplier() {
-        throw new ExerciseNotCompletedException();
+        return String::repeat;
     }
 
     /**
@@ -50,7 +51,7 @@ public static BiFunction<String, Integer, String> stringMultiplier() {
      * @return function that converts adds dollar sign
      */
     public static Function<BigDecimal, String> toDollarStringFunction() {
-        throw new ExerciseNotCompletedException();
+        return big -> String.format("$%s", big);
     }
 
     /**
@@ -62,7 +63,7 @@ public static Function<BigDecimal, String> toDollarStringFunction() {
      * @return a string predicate
      */
     public static Predicate<String> lengthInRangePredicate(int min, int max) {
-        throw new ExerciseNotCompletedException();
+        return str -> min <= str.length() && str.length() < max;
     }
 
     /**
@@ -71,7 +72,7 @@ public static Predicate<String> lengthInRangePredicate(int min, int max) {
      * @return int supplier
      */
     public static IntSupplier randomIntSupplier() {
-        throw new ExerciseNotCompletedException();
+        return () -> ThreadLocalRandom.current().nextInt();
     }
 
 
@@ -81,7 +82,7 @@ public static IntSupplier randomIntSupplier() {
      * @return int operation
      */
     public static IntUnaryOperator boundedRandomIntSupplier() {
-        throw new ExerciseNotCompletedException();
+        return  bound -> ThreadLocalRandom.current().nextInt(bound);
     }
 
     /**
@@ -90,7 +91,7 @@ public static IntUnaryOperator boundedRandomIntSupplier() {
      * @return square operation
      */
     public static IntUnaryOperator intSquareOperation() {
-        throw new ExerciseNotCompletedException();
+        return len -> len * len;
     }
 
     /**
@@ -99,7 +100,7 @@ public static IntUnaryOperator intSquareOperation() {
      * @return binary sum operation
      */
     public static LongBinaryOperator longSumOperation() {
-        throw new ExerciseNotCompletedException();
+        return Long::sum;
     }
 
     /**
@@ -108,7 +109,7 @@ public static LongBinaryOperator longSumOperation() {
      * @return string to int converter
      */
     public static ToIntFunction<String> stringToIntConverter() {
-        throw new ExerciseNotCompletedException();
+        return Integer::parseInt;
     }
 
     /**
@@ -119,7 +120,7 @@ public static ToIntFunction<String> stringToIntConverter() {
      * @return a function supplier
      */
     public static Supplier<IntUnaryOperator> nMultiplyFunctionSupplier(int n) {
-        throw new ExerciseNotCompletedException();
+        return () -> x -> x * n;
     }
 
     /**
@@ -128,7 +129,7 @@ public static Supplier<IntUnaryOperator> nMultiplyFunctionSupplier(int n) {
      * @return function that composes functions with trim() function
      */
     public static UnaryOperator<Function<String, String>> composeWithTrimFunction() {
-        throw new ExerciseNotCompletedException();
+        return function -> function.compose(String::trim);
     }
 
     /**
@@ -139,7 +140,11 @@ public static UnaryOperator<Function<String, String>> composeWithTrimFunction()
      * @return a thread supplier
      */
     public static Supplier<Thread> runningThreadSupplier(Runnable runnable) {
-        throw new ExerciseNotCompletedException();
+        return () -> {
+            Thread thread = new Thread(runnable);
+            thread.start();
+            return thread;
+        };
     }
 
     /**
@@ -148,7 +153,7 @@ public static Supplier<Thread> runningThreadSupplier(Runnable runnable) {
      * @return a runnable consumer
      */
     public static Consumer<Runnable> newThreadRunnableConsumer() {
-        throw new ExerciseNotCompletedException();
+        return Runnable::run;
     }
 
     /**
@@ -158,7 +163,7 @@ public static Consumer<Runnable> newThreadRunnableConsumer() {
      * @return a function that transforms runnable into a thread supplier
      */
     public static Function<Runnable, Supplier<Thread>> runnableToThreadSupplierFunction() {
-        throw new ExerciseNotCompletedException();
+        return CrazyLambdas::runningThreadSupplier;
     }
 
     /**