docs: update .all-contributorsrc [skip ci]

* #1310 Implemented registry pattern

* fixed parent pom version

* added empty line in registry.urm.puml

Co-authored-by: Subhrodip Mohanta <subhrodipmohanta@gmail.com>

.all-contributorsrc

@@ -1296,6 +1296,33 @@
       "contributions": [
         "doc"
       ]
+    },
+    {
+      "login": "omk13",
+      "name": "Omar Karazoun",
+      "avatar_url": "https://avatars0.githubusercontent.com/u/59054172?v=4",
+      "profile": "https://github.com/omk13",
+      "contributions": [
+        "code"
+      ]
+    },
+    {
+      "login": "jeff303",
+      "name": "Jeff Evans",
+      "avatar_url": "https://avatars0.githubusercontent.com/u/3521562?v=4",
+      "profile": "https://github.com/jeff303",
+      "contributions": [
+        "code"
+      ]
+    },
+    {
+      "login": "viveksb007",
+      "name": "Vivek Singh",
+      "avatar_url": "https://avatars1.githubusercontent.com/u/12713808?v=4",
+      "profile": "https://viveksb007.github.io",
+      "contributions": [
+        "code"
+      ]
     }
   ],
   "contributorsPerLine": 4,

README.md

@@ -10,7 +10,7 @@
 [![Coverage](https://sonarcloud.io/api/project_badges/measure?project=iluwatar_java-design-patterns&metric=coverage)](https://sonarcloud.io/dashboard?id=iluwatar_java-design-patterns)
 [![Join the chat at https://gitter.im/iluwatar/java-design-patterns](https://badges.gitter.im/Join%20Chat.svg)](https://gitter.im/iluwatar/java-design-patterns?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge)
 <!-- ALL-CONTRIBUTORS-BADGE:START - Do not remove or modify this section -->
-[![All Contributors](https://img.shields.io/badge/all_contributors-142-orange.svg?style=flat-square)](#contributors-)
+[![All Contributors](https://img.shields.io/badge/all_contributors-145-orange.svg?style=flat-square)](#contributors-)
 <!-- ALL-CONTRIBUTORS-BADGE:END -->
 
 # Introduction
@@ -282,6 +282,11 @@ This project is licensed under the terms of the MIT license.
   <tr>
     <td align="center"><a href="https://ibrahimalii.github.io/"><img src="https://avatars2.githubusercontent.com/u/21141301?v=4" width="100px;" alt=""/><br /><sub><b>Ibrahim ali abdelghany</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/pulls?q=is%3Apr+reviewed-by%3AibrahimAlii" title="Reviewed Pull Requests">👀</a></td>
     <td align="center"><a href="https://github.com/gkulkarni2020"><img src="https://avatars3.githubusercontent.com/u/5161548?v=4" width="100px;" alt=""/><br /><sub><b>Girish Kulkarni</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=gkulkarni2020" title="Documentation">📖</a></td>
+    <td align="center"><a href="https://github.com/omk13"><img src="https://avatars0.githubusercontent.com/u/59054172?v=4" width="100px;" alt=""/><br /><sub><b>Omar Karazoun</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=omk13" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/jeff303"><img src="https://avatars0.githubusercontent.com/u/3521562?v=4" width="100px;" alt=""/><br /><sub><b>Jeff Evans</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=jeff303" title="Code">💻</a></td>
+  </tr>
+  <tr>
+    <td align="center"><a href="https://viveksb007.github.io"><img src="https://avatars1.githubusercontent.com/u/12713808?v=4" width="100px;" alt=""/><br /><sub><b>Vivek Singh</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=viveksb007" title="Code">💻</a></td>
   </tr>
 </table>
 

pom.xml

@@ -195,6 +195,7 @@
         <module>strangler</module>
         <module>arrange-act-assert</module>
         <module>transaction-script</module>
+        <module>registry</module>
         <module>filterer</module>
         <module>factory</module>
         <module>separated-interface</module>

registry/README.md

@@ -0,0 +1,86 @@
+---
+layout: pattern
+title: Registry
+folder: registry
+permalink: /patterns/registry/
+categories: Creational
+tags:
+ - Instantiation
+---
+
+## Intent
+Stores the objects of a single class and provide a global point of access to them. 
+Similar to Multiton pattern, only difference is that in a registry there is no restriction on the number of objects.
+
+## Explanation
+
+In Plain Words
+
+> Registry is a well-known object that other objects can use to find common objects and services.
+
+**Programmatic Example**
+Below is a `Customer` Class
+
+```java
+public class Customer {
+
+  private final String id;
+  private final String name;
+
+  public Customer(String id, String name) {
+    this.id = id;
+    this.name = name;
+  }
+
+  public String getId() {
+    return id;
+  }
+
+  public String getName() {
+    return name;
+  }
+
+}
+```
+
+This registry of the `Customer` objects is `CustomerRegistry`
+```java
+public final class CustomerRegistry {
+
+  private static final CustomerRegistry instance = new CustomerRegistry();
+
+  public static CustomerRegistry getInstance() {
+    return instance;
+  }
+
+  private final Map<String, Customer> customerMap;
+
+  private CustomerRegistry() {
+    customerMap = new ConcurrentHashMap<>();
+  }
+
+  public Customer addCustomer(Customer customer) {
+    return customerMap.put(customer.getId(), customer);
+  }
+
+  public Customer getCustomer(String id) {
+    return customerMap.get(id);
+  }
+
+}
+```
+
+## Class diagram
+![Registry](./etc/registry.png)
+
+## Applicability
+Use Registry pattern when 
+
+* client wants reference of some object, so client can lookup for that object in the object's registry.
+
+## Consequences
+Large number of bulky objects added to registry would result in a lot of memory consumption as objects in the registry are not garbage collected.
+
+## Credits
+* https://www.martinfowler.com/eaaCatalog/registry.html
+* https://wiki.c2.com/?RegistryPattern

registry/etc/registry.urm.puml

@@ -0,0 +1,21 @@
+@startuml
+package com.iluwatar.registry {
+  class App {
+    - LOGGER : Logger {static}
+    + App()
+    + main(args : String[]) {static}
+  }
+  class Customer {
+    - id : String
+    - name : String
+    + getId() : String
+    + getName() : String
+    + toString() : String
+  }
+  class CustomerRegistry {
+    + addCustomer(customer : Customer)
+    + getCustomer(id : String)
+  }
+}
+Customer --> "-addCustomer" CustomerRegistry
+@enduml

registry/pom.xml

@@ -0,0 +1,46 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<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">
+  <modelVersion>4.0.0</modelVersion>
+
+  <parent>
+    <groupId>com.iluwatar</groupId>
+    <artifactId>java-design-patterns</artifactId>
+    <version>1.24.0-SNAPSHOT</version>
+  </parent>
+  <artifactId>registry</artifactId>
+
+  <dependencies>
+    <dependency>
+      <groupId>org.junit.jupiter</groupId>
+      <artifactId>junit-jupiter-engine</artifactId>
+      <scope>test</scope>
+    </dependency>
+    <dependency>
+      <groupId>junit</groupId>
+      <artifactId>junit</artifactId>
+    </dependency>
+  </dependencies>
+
+  <build>
+    <plugins>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-assembly-plugin</artifactId>
+        <executions>
+          <execution>
+            <configuration>
+              <archive>
+                <manifest>
+                  <mainClass>com.iluwatar.registry.App</mainClass>
+                </manifest>
+              </archive>
+            </configuration>
+          </execution>
+        </executions>
+      </plugin>
+    </plugins>
+  </build>
+
+</project>

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

@@ -0,0 +1,27 @@
+package com.iluwatar.registry;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public class App {
+
+  private static final Logger LOGGER = LoggerFactory.getLogger(App.class);
+
+  /**
+   * Program entry point.
+   *
+   * @param args command line args
+   */
+  public static void main(String[] args) {
+    CustomerRegistry customerRegistry = CustomerRegistry.getInstance();
+    var john = new Customer("1", "John");
+    customerRegistry.addCustomer(john);
+
+    var julia = new Customer("2", "Julia");
+    customerRegistry.addCustomer(julia);
+
+    LOGGER.info("John {}", customerRegistry.getCustomer("1"));
+    LOGGER.info("Julia {}", customerRegistry.getCustomer("2"));
+  }
+
+}

registry/src/main/java/com/iluwatar/registry/Customer.java

@@ -0,0 +1,28 @@
+package com.iluwatar.registry;
+
+public class Customer {
+
+  private final String id;
+  private final String name;
+
+  public Customer(String id, String name) {
+    this.id = id;
+    this.name = name;
+  }
+
+  public String getId() {
+    return id;
+  }
+
+  public String getName() {
+    return name;
+  }
+
+  @Override
+  public String toString() {
+    return "Customer{"
+        + "id='" + id + '\''
+        + ", name='" + name + '\''
+        + '}';
+  }
+}

registry/src/main/java/com/iluwatar/registry/CustomerRegistry.java

@@ -0,0 +1,28 @@
+package com.iluwatar.registry;
+
+import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
+
+public final class CustomerRegistry {
+
+  private static final CustomerRegistry instance = new CustomerRegistry();
+
+  public static CustomerRegistry getInstance() {
+    return instance;
+  }
+
+  private final Map<String, Customer> customerMap;
+
+  private CustomerRegistry() {
+    customerMap = new ConcurrentHashMap<>();
+  }
+
+  public Customer addCustomer(Customer customer) {
+    return customerMap.put(customer.getId(), customer);
+  }
+
+  public Customer getCustomer(String id) {
+    return customerMap.get(id);
+  }
+
+}

registry/src/test/java/com/iluwatar/registry/CustomerRegistryTest.java

@@ -0,0 +1,44 @@
+package com.iluwatar.registry;
+
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertNull;
+
+public class CustomerRegistryTest {
+
+  private static CustomerRegistry customerRegistry;
+
+  @BeforeAll
+  public static void setUp() {
+    customerRegistry = CustomerRegistry.getInstance();
+  }
+
+  @Test
+  public void shouldBeAbleToAddAndQueryCustomerObjectFromRegistry() {
+    Customer john = new Customer("1", "john");
+    Customer julia = new Customer("2", "julia");
+
+    customerRegistry.addCustomer(john);
+    customerRegistry.addCustomer(julia);
+
+    Customer customerWithId1 = customerRegistry.getCustomer("1");
+    assertNotNull(customerWithId1);
+    assertEquals("1", customerWithId1.getId());
+    assertEquals("john", customerWithId1.getName());
+
+    Customer customerWithId2 = customerRegistry.getCustomer("2");
+    assertNotNull(customerWithId2);
+    assertEquals("2", customerWithId2.getId());
+    assertEquals("julia", customerWithId2.getName());
+  }
+
+  @Test
+  public void shouldReturnNullWhenQueriedCustomerIsNotInRegistry() {
+    Customer customerWithId5 = customerRegistry.getCustomer("5");
+    assertNull(customerWithId5);
+  }
+
+}