issue iluwatar#335 review changes

monad/index.md

@@ -17,7 +17,7 @@ together step by step. Binding functions can be described as passing one's outpu
 basing on the 'same type' contract. Formally, monad consists of a type constructor M and two
 operations:
 bind - that takes monadic object and a function from plain object to monadic value and returns monadic value
-return - that takse plain type object and returns this object wrapped in a monadic value.
+return - that takes plain type object and returns this object wrapped in a monadic value.
 
 ![alt text](./etc/monad.png "Monad")
 

monad/src/main/java/com/iluwatar/monad/App.java

@@ -1,7 +1,23 @@
 package com.iluwatar.monad;
 
 import java.util.Objects;
+import java.util.function.Function;
+import java.util.function.Predicate;
 
+/**
+ * The Monad pattern defines a monad structure, that enables chaining operations
+ * in pipelines and processing data step by step.
+ * Formally, monad consists of a type constructor M and two operations:
+ * <br>bind - that takes monadic object and a function from plain object to the
+ * monadic value and returns monadic value.
+ * <br>return - that takes plain type object and returns this object wrapped in a monadic value.
+ * <p>
+ * In the given example, the Monad pattern is represented as a {@link Validator} that takes an instance
+ * of a plain object with {@link Validator#of(Object)}
+ * and validates it {@link Validator#validate(Function, Predicate, String)} against given predicates.
+ * <p>As a validation result {@link Validator#get()} it either returns valid object {@link Validator#t}
+ * or throws a list of exceptions {@link Validator#exceptions} collected during validation.
+ */
 public class App {
 
   /**

monad/src/test/java/com/iluwatar/monad/MonadTest.java

@@ -24,19 +24,19 @@ public void testForInvalidName() {
   public void testForInvalidAge() {
     thrown.expect(IllegalStateException.class);
     User john = new User("John", 17, Sex.MALE, "[email protected]");
-    Validator.of(tom).validate(User::getName, Objects::nonNull, "name cannot be null")
+    Validator.of(john).validate(User::getName, Objects::nonNull, "name cannot be null")
         .validate(User::getAge, age -> age > 21, "user is underaged")
         .get();
   }
 
   @Test
   public void testForValid() {
     User sarah = new User("Sarah", 42, Sex.FEMALE, "[email protected]");
-    User validated = Validator.of(tom).validate(User::getName, Objects::nonNull, "name cannot be null")
+    User validated = Validator.of(sarah).validate(User::getName, Objects::nonNull, "name cannot be null")
         .validate(User::getAge, age -> age > 21, "user is underaged")
         .validate(User::getSex, sex -> sex == Sex.FEMALE, "user is not female")
         .validate(User::getEmail, email -> email.contains("@"), "email does not contain @ sign")
         .get();
-    Assert.assertSame(validated, tom);
+    Assert.assertSame(validated, sarah);
   }
 }