[JAVA-621] core-java-lang-oop-types module

* Creation

* Moved code from https://www.baeldung.com/java-marker-interfaces

* Moved code from https://www.baeldung.com/java-abstract-class

* Moved code from https://www.baeldung.com/java-this

* Moved code from https://www.baeldung.com/java-nested-classes

* Moved code from https://www.baeldung.com/java-inner-interfaces

* Moved code from https://www.baeldung.com/java-classes-objects

* Moved article references to the new README.md

core-java-modules/core-java-lang-oop-3/README.md

@@ -5,9 +5,5 @@ This module contains articles about Object-oriented programming (OOP) in Java
 ### Relevant Articles: 
 - [Pass-By-Value as a Parameter Passing Mechanism in Java](https://www.baeldung.com/java-pass-by-value-or-pass-by-reference)
 - [Guide to the super Java Keyword](https://www.baeldung.com/java-super)
-- [Guide to the this Java Keyword](https://www.baeldung.com/java-this)
-- [Nested Classes in Java](https://www.baeldung.com/java-nested-classes)
-- [A Guide to Inner Interfaces in Java](https://www.baeldung.com/java-inner-interfaces)
-- [Java Classes and Objects](https://www.baeldung.com/java-classes-objects)
 - [Java Interfaces](https://www.baeldung.com/java-interfaces)
 - [[<-- Prev]](/core-java-modules/core-java-lang-oop-2)[[More -->]](/core-java-modules/core-java-lang-oop-4)

core-java-modules/core-java-lang-oop-3/src/main/java/com/baeldung/keyword/KeywordDemo.java

@@ -1,7 +1,6 @@
 package com.baeldung.keyword;
 
 import com.baeldung.keyword.superkeyword.SuperSub;
-import com.baeldung.keyword.thiskeyword.KeywordUnitTest;
 
 /**
  * Created by Gebruiker on 5/14/2018.
@@ -9,8 +8,6 @@ import com.baeldung.keyword.thiskeyword.KeywordUnitTest;
 public class KeywordDemo {
 
     public static void main(String[] args) {
-        KeywordUnitTest keyword = new KeywordUnitTest();
-
         SuperSub child = new SuperSub("message from the child class");
     }
 }

core-java-modules/core-java-lang-oop-modules/core-java-lang-oop-types/README.md

@@ -0,0 +1,11 @@
+## Core Java Lang OOP - Types
+
+This module contains articles about types in Java
+
+### Relevant Articles: 
+- [Java Classes and Objects](https://www.baeldung.com/java-classes-objects)
+- [Guide to the this Java Keyword](https://www.baeldung.com/java-this)
+- [Abstract Classes in Java](https://www.baeldung.com/java-abstract-class)
+- [Nested Classes in Java](https://www.baeldung.com/java-nested-classes)
+- [A Guide to Inner Interfaces in Java](https://www.baeldung.com/java-inner-interfaces)
+- [Marker Interfaces in Java](https://www.baeldung.com/java-marker-interfaces)

core-java-modules/core-java-lang-oop-modules/core-java-lang-oop-types/pom.xml

@@ -0,0 +1,28 @@
+<?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">
+    <parent>
+        <artifactId>core-java-lang-oop-modules</artifactId>
+        <groupId>com.baeldung.core-java-lang-oop-modules</groupId>
+        <version>1.0.0-SNAPSHOT</version>
+    </parent>
+    <modelVersion>4.0.0</modelVersion>
+
+    <artifactId>core-java-lang-oop-types</artifactId>
+    <name>core-java-lang-oop-types</name>
+    <packaging>jar</packaging>
+
+    <dependencies>
+        <dependency>
+            <groupId>org.assertj</groupId>
+            <artifactId>assertj-core</artifactId>
+            <version>${assertj-core.version}</version>
+            <scope>test</scope>
+        </dependency>
+    </dependencies>
+
+    <properties>
+        <assertj-core.version>3.10.0</assertj-core.version>
+    </properties>
+</project>

core-java-modules/core-java-lang-oop-modules/core-java-lang-oop-types/src/main/resources/files/test.txt

@@ -0,0 +1,10 @@
+This is line 1
+This is line 2
+This is line 3
+This is line 4
+This is line 5
+This is line 6
+This is line 7
+This is line 8
+This is line 9
+This is line 10

core-java-modules/core-java-lang-oop-modules/pom.xml

@@ -19,5 +19,6 @@
         <module>core-java-lang-oop-patterns</module>
         <module>core-java-lang-oop-generics</module>
         <module>core-java-lang-oop-modifiers</module>
+        <module>core-java-lang-oop-types</module>
     </modules>
 </project>