From 67996222ca6fe57caf2753f067e0aa2330f48e48 Mon Sep 17 00:00:00 2001
From: Janus <januslinhc@hotmail.com>
Date: Fri, 15 Oct 2021 00:12:03 +0800
Subject: [PATCH 01/21] Add currying pattern code

---
 currying/pom.xml                              | 43 ++++++++++++
 .../java/com/iluwatar/currying/Staff.java     | 65 +++++++++++++++++++
 pom.xml                                       |  1 +
 3 files changed, 109 insertions(+)
 create mode 100644 currying/pom.xml
 create mode 100644 currying/src/main/java/com/iluwatar/currying/Staff.java

diff --git a/currying/pom.xml b/currying/pom.xml
new file mode 100644
index 000000000000..b86c13c28395
--- /dev/null
+++ b/currying/pom.xml
@@ -0,0 +1,43 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+
+    The MIT License
+    Copyright (c) 2014-2016 Ilkka Seppälä
+
+    Permission is hereby granted, free of charge, to any person obtaining a copy
+    of this software and associated documentation files (the "Software"), to deal
+    in the Software without restriction, including without limitation the rights
+    to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+    copies of the Software, and to permit persons to whom the Software is
+    furnished to do so, subject to the following conditions:
+
+    The above copyright notice and this permission notice shall be included in
+    all copies or substantial portions of the Software.
+
+    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+    IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+    AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+    LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+    OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+    THE SOFTWARE.
+
+-->
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <parent>
+        <artifactId>java-design-patterns</artifactId>
+        <groupId>com.iluwatar</groupId>
+        <version>1.18.0-SNAPSHOT</version>
+    </parent>
+    <modelVersion>4.0.0</modelVersion>
+    <artifactId>currying</artifactId>
+    <dependencies>
+        <dependency>
+            <groupId>junit</groupId>
+            <artifactId>junit</artifactId>
+            <scope>test</scope>
+        </dependency>
+    </dependencies>
+</project>
\ No newline at end of file
diff --git a/currying/src/main/java/com/iluwatar/currying/Staff.java b/currying/src/main/java/com/iluwatar/currying/Staff.java
new file mode 100644
index 000000000000..571c580d7a57
--- /dev/null
+++ b/currying/src/main/java/com/iluwatar/currying/Staff.java
@@ -0,0 +1,65 @@
+package com.iluwatar.currying;
+
+import java.time.LocalDate;
+import java.util.Objects;
+import java.util.function.Function;
+
+public class Staff {
+    private String firstName;
+    private String lastName;
+    private Gender gender;
+    private String email;
+    private LocalDate dateOfBirth;
+
+    public Staff(String firstName, String lastName, Gender gender, String email, LocalDate dateOfBirth) {
+        this.firstName = firstName;
+        this.lastName = lastName;
+        this.gender = gender;
+        this.email = email;
+        this.dateOfBirth = dateOfBirth;
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (o == null || getClass() != o.getClass()) return false;
+        Staff staff = (Staff) o;
+        return firstName.equals(staff.firstName) && lastName.equals(staff.lastName) && gender == staff.gender && email.equals(staff.email) && dateOfBirth.equals(staff.dateOfBirth);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(firstName, lastName, gender, email, dateOfBirth);
+    }
+
+    static Function<String, Function<String, Function<Gender, Function<String, Function<LocalDate, Staff>>>>> CREATOR =
+            firstName -> lastName -> gender -> email -> dateOfBirth -> new Staff(firstName, lastName, gender, email, dateOfBirth);
+
+    static AddFirstName builder() {
+        return firstName -> lastName -> gender -> email -> dateOfBirth -> new Staff(firstName, lastName, gender, email, dateOfBirth);
+    }
+
+    interface AddFirstName {
+        AddLastName withReturnFirstName(String firstName);
+    }
+
+    interface AddLastName {
+        AddGender withReturnLastName(String lastName);
+    }
+
+    interface AddGender {
+        AddEmail withReturnGender(Gender gender);
+    }
+
+    interface AddEmail {
+        AddDateOfBirth withReturnEmail(String email);
+    }
+
+    interface AddDateOfBirth {
+        Staff withReturnDateOfBirth(LocalDate dateOfBirth);
+    }
+
+    enum Gender {
+        Male, Female
+    }
+}
diff --git a/pom.xml b/pom.xml
index f94b9923006a..7eccd94088ed 100644
--- a/pom.xml
+++ b/pom.xml
@@ -152,6 +152,7 @@
         <module>eip-splitter</module>
         <module>eip-aggregator</module>
         <module>retry</module>
+        <module>currying</module>
     </modules>
 
     <dependencyManagement>

From e3b95853a78e9930fc36082e8161038ed09f66bb Mon Sep 17 00:00:00 2001
From: Janus <januslinhc@hotmail.com>
Date: Fri, 15 Oct 2021 00:13:14 +0800
Subject: [PATCH 02/21] Add currying pattern code

---
 .../java/com/iluwatar/currying/StaffTest.java | 38 +++++++++++++++++++
 1 file changed, 38 insertions(+)
 create mode 100644 currying/src/test/java/com/iluwatar/currying/StaffTest.java

diff --git a/currying/src/test/java/com/iluwatar/currying/StaffTest.java b/currying/src/test/java/com/iluwatar/currying/StaffTest.java
new file mode 100644
index 000000000000..8a65bbe727fd
--- /dev/null
+++ b/currying/src/test/java/com/iluwatar/currying/StaffTest.java
@@ -0,0 +1,38 @@
+package com.iluwatar.currying;
+
+import org.junit.Assert;
+import org.junit.Test;
+
+import java.time.LocalDate;
+
+public class StaffTest {
+    private final String firstName = "Janus";
+    private final String lastName = "Lin";
+    private final Staff.Gender gender = Staff.Gender.Male;
+    private final String email = "example@gmail.com";
+    private final LocalDate dateOfBirth = LocalDate.now();
+
+    private final Staff expectedResult = new Staff(firstName, lastName, gender, email, dateOfBirth);
+
+    @Test
+    public void createStaffWithBasicCurrying() {
+        Staff actualResult = Staff.CREATOR
+                .apply(firstName)
+                .apply(lastName)
+                .apply(gender)
+                .apply(email)
+                .apply(dateOfBirth);
+        Assert.assertEquals(expectedResult, actualResult);
+    }
+
+    @Test
+    public void createStaffWithFunctionalInterface() {
+        Staff actualResult = Staff.builder()
+                .withReturnFirstName(firstName)
+                .withReturnLastName(lastName)
+                .withReturnGender(gender)
+                .withReturnEmail(email)
+                .withReturnDateOfBirth(dateOfBirth);
+        Assert.assertEquals(expectedResult, actualResult);
+    }
+}

From 79327dc03222af644f564166cfd63837459a05d8 Mon Sep 17 00:00:00 2001
From: Janus <januslinhc@hotmail.com>
Date: Fri, 15 Oct 2021 00:51:34 +0800
Subject: [PATCH 03/21] Add currying pattern code

---
 currying/src/main/java/com/iluwatar/currying/Staff.java | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/currying/src/main/java/com/iluwatar/currying/Staff.java b/currying/src/main/java/com/iluwatar/currying/Staff.java
index 571c580d7a57..254cd701e9ca 100644
--- a/currying/src/main/java/com/iluwatar/currying/Staff.java
+++ b/currying/src/main/java/com/iluwatar/currying/Staff.java
@@ -32,9 +32,15 @@ public int hashCode() {
         return Objects.hash(firstName, lastName, gender, email, dateOfBirth);
     }
 
+    /**
+     * Use {@link Function} for currying
+     */
     static Function<String, Function<String, Function<Gender, Function<String, Function<LocalDate, Staff>>>>> CREATOR =
             firstName -> lastName -> gender -> email -> dateOfBirth -> new Staff(firstName, lastName, gender, email, dateOfBirth);
 
+    /**
+     * Use functional interfaces for currying
+     */
     static AddFirstName builder() {
         return firstName -> lastName -> gender -> email -> dateOfBirth -> new Staff(firstName, lastName, gender, email, dateOfBirth);
     }

From 7e4bc40f64563babcbe255ba5a9dc06dc1e263ce Mon Sep 17 00:00:00 2001
From: Janus <januslinhc@hotmail.com>
Date: Fri, 15 Oct 2021 00:53:57 +0800
Subject: [PATCH 04/21] Add README for currying

---
 currying/README.md | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)
 create mode 100644 currying/README.md

diff --git a/currying/README.md b/currying/README.md
new file mode 100644
index 000000000000..101c98438a68
--- /dev/null
+++ b/currying/README.md
@@ -0,0 +1,24 @@
+---
+layout: pattern
+title: Currying
+folder: currying
+permalink: /patterns/currying/
+categories: Architectural
+tags:
+- Java
+- Difficulty-Intermediate
+---
+
+## Intent
+Currying pattern is a function that returns another function which only takes 1 parameter at a time.
+
+![alt text](./etc/dao.png "Data Access Object")
+
+## Applicability
+Use the currying pattern in any of the following situations
+
+* when you want to break a function with many arguments into many functions with single argument 
+
+## Credits
+
+* [J2EE Design Patterns](http://www.amazon.com/J2EE-Design-Patterns-William-Crawford/dp/0596004273/ref=sr_1_2)

From a9f875b56e20394bbf4111c2585cd57d8ae66925 Mon Sep 17 00:00:00 2001
From: januslinhc <januslinhc@users.noreply.github.com>
Date: Mon, 18 Oct 2021 23:53:45 +0800
Subject: [PATCH 05/21] Remove wrong credit

---
 currying/README.md | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/currying/README.md b/currying/README.md
index 101c98438a68..636931447af3 100644
--- a/currying/README.md
+++ b/currying/README.md
@@ -18,7 +18,3 @@ Currying pattern is a function that returns another function which only takes 1
 Use the currying pattern in any of the following situations
 
 * when you want to break a function with many arguments into many functions with single argument 
-
-## Credits
-
-* [J2EE Design Patterns](http://www.amazon.com/J2EE-Design-Patterns-William-Crawford/dp/0596004273/ref=sr_1_2)

From 1b902bf128e3a9ac1a18e349dde666eb7c0fc757 Mon Sep 17 00:00:00 2001
From: januslinhc <januslinhc@users.noreply.github.com>
Date: Mon, 18 Oct 2021 23:54:47 +0800
Subject: [PATCH 06/21] fix parent module version

---
 currying/pom.xml | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/currying/pom.xml b/currying/pom.xml
index b86c13c28395..33e2bed1a3b5 100644
--- a/currying/pom.xml
+++ b/currying/pom.xml
@@ -29,7 +29,7 @@
     <parent>
         <artifactId>java-design-patterns</artifactId>
         <groupId>com.iluwatar</groupId>
-        <version>1.18.0-SNAPSHOT</version>
+        <version>1.25.0-SNAPSHOT</version>
     </parent>
     <modelVersion>4.0.0</modelVersion>
     <artifactId>currying</artifactId>
@@ -40,4 +40,4 @@
             <scope>test</scope>
         </dependency>
     </dependencies>
-</project>
\ No newline at end of file
+</project>

From 221e0316d34baf6b243c3e7ca1a9b7949862f5cf Mon Sep 17 00:00:00 2001
From: Janus <januslinhc@hotmail.com>
Date: Tue, 19 Oct 2021 01:20:27 +0800
Subject: [PATCH 07/21] fix style

---
 .../java/com/iluwatar/currying/Staff.java     | 137 +++++++++++-------
 1 file changed, 86 insertions(+), 51 deletions(-)

diff --git a/currying/src/main/java/com/iluwatar/currying/Staff.java b/currying/src/main/java/com/iluwatar/currying/Staff.java
index 254cd701e9ca..9f3539e78d99 100644
--- a/currying/src/main/java/com/iluwatar/currying/Staff.java
+++ b/currying/src/main/java/com/iluwatar/currying/Staff.java
@@ -4,68 +4,103 @@
 import java.util.Objects;
 import java.util.function.Function;
 
+/**
+ * Staff Object for demonstrating how to use currying pattern.
+ */
 public class Staff {
-    private String firstName;
-    private String lastName;
-    private Gender gender;
-    private String email;
-    private LocalDate dateOfBirth;
+  private String firstName;
+  private String lastName;
+  private Gender gender;
+  private String email;
+  private LocalDate dateOfBirth;
 
-    public Staff(String firstName, String lastName, Gender gender, String email, LocalDate dateOfBirth) {
-        this.firstName = firstName;
-        this.lastName = lastName;
-        this.gender = gender;
-        this.email = email;
-        this.dateOfBirth = dateOfBirth;
-    }
+  /**
+   * Contractor.
 
-    @Override
-    public boolean equals(Object o) {
-        if (this == o) return true;
-        if (o == null || getClass() != o.getClass()) return false;
-        Staff staff = (Staff) o;
-        return firstName.equals(staff.firstName) && lastName.equals(staff.lastName) && gender == staff.gender && email.equals(staff.email) && dateOfBirth.equals(staff.dateOfBirth);
-    }
+   * @param firstName first name.
+   * @param lastName last name.
+   * @param gender gender.
+   * @param email email.
+   * @param dateOfBirth date of birth.
+   */
+  public Staff(String firstName,
+               String lastName,
+               Gender gender,
+               String email,
+               LocalDate dateOfBirth) {
+    this.firstName = firstName;
+    this.lastName = lastName;
+    this.gender = gender;
+    this.email = email;
+    this.dateOfBirth = dateOfBirth;
+  }
 
-    @Override
-    public int hashCode() {
-        return Objects.hash(firstName, lastName, gender, email, dateOfBirth);
+  @Override
+  public boolean equals(Object o) {
+    if (this == o) {
+      return true;
+    }
+    if (o == null || getClass() != o.getClass()) {
+      return false;
     }
+    Staff staff = (Staff) o;
+    return firstName.equals(staff.firstName)
+            && lastName.equals(staff.lastName)
+            && gender == staff.gender
+            && email.equals(staff.email)
+            && dateOfBirth.equals(staff.dateOfBirth);
+  }
 
-    /**
-     * Use {@link Function} for currying
-     */
-    static Function<String, Function<String, Function<Gender, Function<String, Function<LocalDate, Staff>>>>> CREATOR =
-            firstName -> lastName -> gender -> email -> dateOfBirth -> new Staff(firstName, lastName, gender, email, dateOfBirth);
+  @Override
+  public int hashCode() {
+    return Objects.hash(firstName, lastName, gender, email, dateOfBirth);
+  }
 
-    /**
-     * Use functional interfaces for currying
-     */
-    static AddFirstName builder() {
-        return firstName -> lastName -> gender -> email -> dateOfBirth -> new Staff(firstName, lastName, gender, email, dateOfBirth);
-    }
+  /**
+   * Use {@link Function} for currying.
+   */
+  static Function<String,
+            Function<String,
+                    Function<Gender,
+                            Function<String,
+                                    Function<LocalDate, Staff>>>>> CREATOR =
+                                        firstName -> lastName
+                                            -> gender -> email
+                                                -> dateOfBirth
+                                                    -> new Staff(firstName, lastName, gender,
+                                                         email, dateOfBirth);
 
-    interface AddFirstName {
-        AddLastName withReturnFirstName(String firstName);
-    }
+  /**
+   * Use functional interfaces for currying.
+   */
+  static AddFirstName builder() {
+    return firstName -> lastName
+        -> gender -> email
+            -> dateOfBirth
+                -> new Staff(firstName, lastName, gender, email, dateOfBirth);
+  }
 
-    interface AddLastName {
-        AddGender withReturnLastName(String lastName);
-    }
+  interface AddFirstName {
+    AddLastName withReturnFirstName(String firstName);
+  }
 
-    interface AddGender {
-        AddEmail withReturnGender(Gender gender);
-    }
+  interface AddLastName {
+    AddGender withReturnLastName(String lastName);
+  }
 
-    interface AddEmail {
-        AddDateOfBirth withReturnEmail(String email);
-    }
+  interface AddGender {
+    AddEmail withReturnGender(Gender gender);
+  }
 
-    interface AddDateOfBirth {
-        Staff withReturnDateOfBirth(LocalDate dateOfBirth);
-    }
+  interface AddEmail {
+    AddDateOfBirth withReturnEmail(String email);
+  }
 
-    enum Gender {
-        Male, Female
-    }
+  interface AddDateOfBirth {
+    Staff withReturnDateOfBirth(LocalDate dateOfBirth);
+  }
+
+  enum Gender {
+    Male, Female
+  }
 }

From b5c50ed57bf755371bd644465df868c9cf1e7619 Mon Sep 17 00:00:00 2001
From: Janus <januslinhc@hotmail.com>
Date: Wed, 20 Oct 2021 00:24:34 +0800
Subject: [PATCH 08/21] add maven-assembly-plugin

---
 currying/pom.xml                              | 19 ++++++++++++
 .../java/com/iluwatar/currying/Staff.java     | 30 +++++++++++++++++++
 2 files changed, 49 insertions(+)

diff --git a/currying/pom.xml b/currying/pom.xml
index 33e2bed1a3b5..14ea821bb78b 100644
--- a/currying/pom.xml
+++ b/currying/pom.xml
@@ -40,4 +40,23 @@
             <scope>test</scope>
         </dependency>
     </dependencies>
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-assembly-plugin</artifactId>
+                <executions>
+                    <execution>
+                        <configuration>
+                            <archive>
+                                <manifest>
+                                    <mainClass>com.iluwatar.dao.App</mainClass>
+                                </manifest>
+                            </archive>
+                        </configuration>
+                    </execution>
+                </executions>
+            </plugin>
+        </plugins>
+    </build>
 </project>
diff --git a/currying/src/main/java/com/iluwatar/currying/Staff.java b/currying/src/main/java/com/iluwatar/currying/Staff.java
index 9f3539e78d99..38e7f3659432 100644
--- a/currying/src/main/java/com/iluwatar/currying/Staff.java
+++ b/currying/src/main/java/com/iluwatar/currying/Staff.java
@@ -103,4 +103,34 @@ interface AddDateOfBirth {
   enum Gender {
     Male, Female
   }
+
+  /**
+   * Main method for maven-assembly-plugin.
+   */
+  public static void main(String[] args) {
+    final String firstName = "Janus";
+    final String lastName = "Lin";
+    final Staff.Gender gender = Staff.Gender.Male;
+    final String email = "example@gmail.com";
+    final LocalDate dateOfBirth = LocalDate.now();
+
+    Staff staff1 = Staff.CREATOR
+            .apply(firstName)
+            .apply(lastName)
+            .apply(gender)
+            .apply(email)
+            .apply(dateOfBirth);
+
+    System.out.println(String.format("Staff created with basic currying: %s", staff1));
+
+    Staff staff2 = Staff.builder()
+            .withReturnFirstName(firstName)
+            .withReturnLastName(lastName)
+            .withReturnGender(gender)
+            .withReturnEmail(email)
+            .withReturnDateOfBirth(dateOfBirth);
+
+    System.out.println(
+            String.format("Staff created with currying and functional interfaces: %s", staff2));
+  }
 }

From 7e4c34c002657dcedfa9f3f17755e98e4ed4f380 Mon Sep 17 00:00:00 2001
From: Janus <januslinhc@hotmail.com>
Date: Wed, 20 Oct 2021 00:28:40 +0800
Subject: [PATCH 09/21] Use Lombok to get rid of boilerplate

---
 .../java/com/iluwatar/currying/Staff.java     | 47 ++-----------------
 1 file changed, 5 insertions(+), 42 deletions(-)

diff --git a/currying/src/main/java/com/iluwatar/currying/Staff.java b/currying/src/main/java/com/iluwatar/currying/Staff.java
index 38e7f3659432..e58f88249d7a 100644
--- a/currying/src/main/java/com/iluwatar/currying/Staff.java
+++ b/currying/src/main/java/com/iluwatar/currying/Staff.java
@@ -1,5 +1,8 @@
 package com.iluwatar.currying;
 
+import lombok.AllArgsConstructor;
+import lombok.Data;
+
 import java.time.LocalDate;
 import java.util.Objects;
 import java.util.function.Function;
@@ -7,6 +10,8 @@
 /**
  * Staff Object for demonstrating how to use currying pattern.
  */
+@AllArgsConstructor
+@Data
 public class Staff {
   private String firstName;
   private String lastName;
@@ -14,48 +19,6 @@ public class Staff {
   private String email;
   private LocalDate dateOfBirth;
 
-  /**
-   * Contractor.
-
-   * @param firstName first name.
-   * @param lastName last name.
-   * @param gender gender.
-   * @param email email.
-   * @param dateOfBirth date of birth.
-   */
-  public Staff(String firstName,
-               String lastName,
-               Gender gender,
-               String email,
-               LocalDate dateOfBirth) {
-    this.firstName = firstName;
-    this.lastName = lastName;
-    this.gender = gender;
-    this.email = email;
-    this.dateOfBirth = dateOfBirth;
-  }
-
-  @Override
-  public boolean equals(Object o) {
-    if (this == o) {
-      return true;
-    }
-    if (o == null || getClass() != o.getClass()) {
-      return false;
-    }
-    Staff staff = (Staff) o;
-    return firstName.equals(staff.firstName)
-            && lastName.equals(staff.lastName)
-            && gender == staff.gender
-            && email.equals(staff.email)
-            && dateOfBirth.equals(staff.dateOfBirth);
-  }
-
-  @Override
-  public int hashCode() {
-    return Objects.hash(firstName, lastName, gender, email, dateOfBirth);
-  }
-
   /**
    * Use {@link Function} for currying.
    */

From 8cd16fef8351cfb882a615a0c2ebc4c639918304 Mon Sep 17 00:00:00 2001
From: Janus <januslinhc@hotmail.com>
Date: Wed, 20 Oct 2021 00:30:15 +0800
Subject: [PATCH 10/21] Update tags in README.md

---
 currying/README.md | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/currying/README.md b/currying/README.md
index 636931447af3..43a2defac25a 100644
--- a/currying/README.md
+++ b/currying/README.md
@@ -5,8 +5,7 @@ folder: currying
 permalink: /patterns/currying/
 categories: Architectural
 tags:
-- Java
-- Difficulty-Intermediate
+- Decoupling
 ---
 
 ## Intent

From 077bd4517ae7949bd0dfccc661472ef08357d9d6 Mon Sep 17 00:00:00 2001
From: Janus <januslinhc@hotmail.com>
Date: Wed, 20 Oct 2021 00:30:59 +0800
Subject: [PATCH 11/21] Update categories in README.md

---
 currying/README.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/currying/README.md b/currying/README.md
index 43a2defac25a..b70b9b6cf141 100644
--- a/currying/README.md
+++ b/currying/README.md
@@ -3,7 +3,7 @@ layout: pattern
 title: Currying
 folder: currying
 permalink: /patterns/currying/
-categories: Architectural
+categories: Functional
 tags:
 - Decoupling
 ---

From bcedc3f3135a34d02d4f36c3d200b30819b4b8cc Mon Sep 17 00:00:00 2001
From: Janus <januslinhc@hotmail.com>
Date: Wed, 20 Oct 2021 00:31:32 +0800
Subject: [PATCH 12/21] add language in README.md

---
 currying/README.md | 1 +
 1 file changed, 1 insertion(+)

diff --git a/currying/README.md b/currying/README.md
index b70b9b6cf141..72c0f57c39df 100644
--- a/currying/README.md
+++ b/currying/README.md
@@ -4,6 +4,7 @@ title: Currying
 folder: currying
 permalink: /patterns/currying/
 categories: Functional
+language: en
 tags:
 - Decoupling
 ---

From 6332fdd7df8315e9cbb5c62e59e250135962b84c Mon Sep 17 00:00:00 2001
From: Janus <januslinhc@hotmail.com>
Date: Wed, 20 Oct 2021 00:52:29 +0800
Subject: [PATCH 13/21] update Tutorials and Credits sections in README.md

---
 currying/README.md | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/currying/README.md b/currying/README.md
index 72c0f57c39df..c7b8c1663503 100644
--- a/currying/README.md
+++ b/currying/README.md
@@ -10,7 +10,7 @@ tags:
 ---
 
 ## Intent
-Currying pattern is a function that returns another function which only takes 1 parameter at a time.
+Currying pattern transforms an arbitrary arity into a sequence of unary functions.
 
 ![alt text](./etc/dao.png "Data Access Object")
 
@@ -18,3 +18,11 @@ Currying pattern is a function that returns another function which only takes 1
 Use the currying pattern in any of the following situations
 
 * when you want to break a function with many arguments into many functions with single argument 
+
+## Tutorials
+
+* [Currying in Java](https://www.baeldung.com/java-currying)
+
+## Credits
+
+* [Baeldung](https://www.baeldung.com/)
\ No newline at end of file

From ab93ab56c7ad9846e3f204192a2a0ea4ad3727db Mon Sep 17 00:00:00 2001
From: Janus <januslinhc@hotmail.com>
Date: Wed, 20 Oct 2021 01:10:37 +0800
Subject: [PATCH 14/21] add test case for main

---
 currying/src/test/java/com/iluwatar/currying/StaffTest.java | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/currying/src/test/java/com/iluwatar/currying/StaffTest.java b/currying/src/test/java/com/iluwatar/currying/StaffTest.java
index 8a65bbe727fd..dc4e6be9edbf 100644
--- a/currying/src/test/java/com/iluwatar/currying/StaffTest.java
+++ b/currying/src/test/java/com/iluwatar/currying/StaffTest.java
@@ -35,4 +35,9 @@ public void createStaffWithFunctionalInterface() {
                 .withReturnDateOfBirth(dateOfBirth);
         Assert.assertEquals(expectedResult, actualResult);
     }
+
+    @Test
+    public void mainTest() {
+        Staff.main(new String[]{});
+    }
 }

From 20466c4aeeffd83401f8da05977f482c21629a08 Mon Sep 17 00:00:00 2001
From: Janus <januslinhc@hotmail.com>
Date: Mon, 25 Oct 2021 00:24:42 +0800
Subject: [PATCH 15/21] fix merge conflict

---
 dao/pom.xml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/dao/pom.xml b/dao/pom.xml
index d9467aeae899..ffe5444e66d8 100644
--- a/dao/pom.xml
+++ b/dao/pom.xml
@@ -56,7 +56,7 @@
             <configuration>
               <archive>
                 <manifest>
-                  <mainClass>com.iluwatar.dao.App</mainClass>
+                  <mainClass>com.iluwatar.currying.Staff</mainClass>
                 </manifest>
               </archive>
             </configuration>

From 4a93b257db1e28edec7fc1ed8208b4a489c81320 Mon Sep 17 00:00:00 2001
From: Janus <januslinhc@hotmail.com>
Date: Mon, 25 Oct 2021 00:31:54 +0800
Subject: [PATCH 16/21] revert dao change

---
 dao/pom.xml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/dao/pom.xml b/dao/pom.xml
index ffe5444e66d8..d9467aeae899 100644
--- a/dao/pom.xml
+++ b/dao/pom.xml
@@ -56,7 +56,7 @@
             <configuration>
               <archive>
                 <manifest>
-                  <mainClass>com.iluwatar.currying.Staff</mainClass>
+                  <mainClass>com.iluwatar.dao.App</mainClass>
                 </manifest>
               </archive>
             </configuration>

From 9928e7071bc2c9e63111e94f200e0e2feff8967d Mon Sep 17 00:00:00 2001
From: Janus <januslinhc@hotmail.com>
Date: Mon, 25 Oct 2021 00:33:44 +0800
Subject: [PATCH 17/21] remove diagram

---
 currying/README.md | 2 --
 1 file changed, 2 deletions(-)

diff --git a/currying/README.md b/currying/README.md
index c7b8c1663503..e5ab7fdf006a 100644
--- a/currying/README.md
+++ b/currying/README.md
@@ -12,8 +12,6 @@ tags:
 ## Intent
 Currying pattern transforms an arbitrary arity into a sequence of unary functions.
 
-![alt text](./etc/dao.png "Data Access Object")
-
 ## Applicability
 Use the currying pattern in any of the following situations
 

From 34e80af0fde10452de87987508fa27a25aab971b Mon Sep 17 00:00:00 2001
From: Janus <januslinhc@hotmail.com>
Date: Mon, 25 Oct 2021 00:46:43 +0800
Subject: [PATCH 18/21] add test cases

---
 .../java/com/iluwatar/currying/StaffTest.java | 19 +++++++++++++++++--
 1 file changed, 17 insertions(+), 2 deletions(-)

diff --git a/currying/src/test/java/com/iluwatar/currying/StaffTest.java b/currying/src/test/java/com/iluwatar/currying/StaffTest.java
index dc4e6be9edbf..f74dfb532bd8 100644
--- a/currying/src/test/java/com/iluwatar/currying/StaffTest.java
+++ b/currying/src/test/java/com/iluwatar/currying/StaffTest.java
@@ -5,6 +5,8 @@
 
 import java.time.LocalDate;
 
+import static org.junit.Assert.*;
+
 public class StaffTest {
     private final String firstName = "Janus";
     private final String lastName = "Lin";
@@ -22,7 +24,7 @@ public void createStaffWithBasicCurrying() {
                 .apply(gender)
                 .apply(email)
                 .apply(dateOfBirth);
-        Assert.assertEquals(expectedResult, actualResult);
+        assertEquals(expectedResult, actualResult);
     }
 
     @Test
@@ -33,11 +35,24 @@ public void createStaffWithFunctionalInterface() {
                 .withReturnGender(gender)
                 .withReturnEmail(email)
                 .withReturnDateOfBirth(dateOfBirth);
-        Assert.assertEquals(expectedResult, actualResult);
+        assertEquals(expectedResult, actualResult);
     }
 
     @Test
     public void mainTest() {
         Staff.main(new String[]{});
     }
+
+    @Test
+    public void hashTest() {
+        expectedResult.hashCode();
+    }
+
+    @Test
+    public void equalTest() {
+        assertTrue(expectedResult.equals(expectedResult));
+        assertFalse(expectedResult.equals(new Integer(1)));
+        Staff o2 = new Staff(firstName, lastName, gender, email, dateOfBirth);
+        assertTrue(expectedResult.equals(o2));
+    }
 }

From b617468d91ee971b27e18cc5a13b89196b789796 Mon Sep 17 00:00:00 2001
From: Janus <januslinhc@hotmail.com>
Date: Mon, 25 Oct 2021 01:21:41 +0800
Subject: [PATCH 19/21] remove unused import

---
 currying/src/main/java/com/iluwatar/currying/Staff.java | 1 -
 1 file changed, 1 deletion(-)

diff --git a/currying/src/main/java/com/iluwatar/currying/Staff.java b/currying/src/main/java/com/iluwatar/currying/Staff.java
index e58f88249d7a..7ad0ddb0ad2e 100644
--- a/currying/src/main/java/com/iluwatar/currying/Staff.java
+++ b/currying/src/main/java/com/iluwatar/currying/Staff.java
@@ -4,7 +4,6 @@
 import lombok.Data;
 
 import java.time.LocalDate;
-import java.util.Objects;
 import java.util.function.Function;
 
 /**

From fa9d7cc5bf3a03fa58c58cbaa8f94db6a07a9634 Mon Sep 17 00:00:00 2001
From: Janus <januslinhc@hotmail.com>
Date: Mon, 25 Oct 2021 01:33:49 +0800
Subject: [PATCH 20/21] improve README.md

---
 currying/README.md | 116 ++++++++++++++++++++++++++++++++++++++++++---
 1 file changed, 109 insertions(+), 7 deletions(-)

diff --git a/currying/README.md b/currying/README.md
index e5ab7fdf006a..c526220eabb1 100644
--- a/currying/README.md
+++ b/currying/README.md
@@ -1,21 +1,123 @@
 ---
-layout: pattern
-title: Currying
-folder: currying
-permalink: /patterns/currying/
-categories: Functional
-language: en
+layout: pattern title: Currying folder: currying permalink: /patterns/currying/ categories: Functional language: en
 tags:
+
 - Decoupling
+
 ---
 
 ## Intent
+
 Currying pattern transforms an arbitrary arity into a sequence of unary functions.
 
+## Explanation
+
+Real-world example
+
+> We have a Staff class for storing employees' information, e.g. firstName, lastName,
+> gender, email, etc. We want to adapt currying pattern to simplify the parameters handling,
+> we don't need to provide all parameters at the same time. We can provide them one by one
+> when we have that data.
+
+In plain words
+
+> It helps you to avoid passing the same variable again and again.
+> It helps to create a higher order function. It extremely helpful in event handling.
+> Little snippets of code can be written and reused with ease.
+
+Wikipedia says
+
+> Currying provides a way for working with functions that take multiple arguments,
+> and using them in frameworks where functions might take only one argument.
+> For example, some analytical techniques can only be applied to functions with a
+> single argument. Practical functions frequently take more arguments than this.
+> Frege showed that it was sufficient to provide solutions for the single argument
+> case, as it was possible to transform a function with multiple arguments into a
+> chain of single-argument functions instead. This transformation is the process
+> now known as currying.
+
+**Programmatic Example**
+
+First, we have the `Staff` class:
+
+```java
+
+@AllArgsConstructor
+@Data
+public class Staff {
+    private String firstName;
+    private String lastName;
+    private Gender gender;
+    private String email;
+    private LocalDate dateOfBirth;
+}
+```
+
+By using @AllArgsConstructor from Lombok library, it will generate a constructor with all attributes. All paramaters
+need to provide at the same time.
+
+Next, we will try to use Curry pattern to transforms an arbitrary arity into a sequence of unary functions.
+
+```java
+static Function<String,
+        Function<String,
+        Function<Gender,
+        Function<String,
+        Function<LocalDate, Staff>>>>>CREATOR=
+        firstName->lastName
+        ->gender->email
+        ->dateOfBirth
+        ->new Staff(firstName,lastName,gender,
+        email,dateOfBirth);
+```
+
+With using this way, we can create Staff object by providing parameters one by one:
+
+```java
+Staff.CREATOR
+        .apply(firstName)
+        .apply(lastName)
+        .apply(gender)
+        .apply(email)
+        .apply(dateOfBirth);
+```
+
+We can also use Functional Interface to implement currying function.
+
+```java
+static AddFirstName builder(){
+        return firstName->lastName
+        ->gender->email
+        ->dateOfBirth
+        ->new Staff(firstName,lastName,gender,email,dateOfBirth);
+        }
+
+interface AddFirstName {
+    AddLastName withReturnFirstName(String firstName);
+}
+
+interface AddLastName {
+    AddGender withReturnLastName(String lastName);
+}
+
+interface AddGender {
+    AddEmail withReturnGender(Gender gender);
+}
+
+interface AddEmail {
+    AddDateOfBirth withReturnEmail(String email);
+}
+
+interface AddDateOfBirth {
+    Staff withReturnDateOfBirth(LocalDate dateOfBirth);
+}
+```
+
 ## Applicability
+
 Use the currying pattern in any of the following situations
 
-* when you want to break a function with many arguments into many functions with single argument 
+* when you want to break a function with many arguments into many functions with single argument
 
 ## Tutorials
 

From 26f4cae685aa0eced910281b546fab96f873a8f1 Mon Sep 17 00:00:00 2001
From: Janus <januslinhc@hotmail.com>
Date: Mon, 25 Oct 2021 01:34:43 +0800
Subject: [PATCH 21/21] fix style

---
 currying/src/main/java/com/iluwatar/currying/Staff.java | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/currying/src/main/java/com/iluwatar/currying/Staff.java b/currying/src/main/java/com/iluwatar/currying/Staff.java
index 7ad0ddb0ad2e..762e0159d550 100644
--- a/currying/src/main/java/com/iluwatar/currying/Staff.java
+++ b/currying/src/main/java/com/iluwatar/currying/Staff.java
@@ -1,10 +1,9 @@
 package com.iluwatar.currying;
 
-import lombok.AllArgsConstructor;
-import lombok.Data;
-
 import java.time.LocalDate;
 import java.util.function.Function;
+import lombok.AllArgsConstructor;
+import lombok.Data;
 
 /**
  * Staff Object for demonstrating how to use currying pattern.