[BAEL-3147] Java 'protected' modifier (eugenp#7886)

* [BAEL-3147] Java 'protected' modifier

* updated README.md

* Update README.md

* Update SecondGenericClass.java

Author: NickTononi

core-java-modules/core-java-lang-syntax-2/src/main/java/com/baeldung/core/modifiers/FirstClass.java

@@ -0,0 +1,18 @@
+package com.baeldung.core.modifiers;
+
+public class FirstClass {
+
+    protected String name;
+    
+    protected FirstClass(String name) {
+        this.name = name;
+    }
+
+    protected String getName() {
+        return name;
+    }
+
+    protected static class InnerClass {
+        public InnerClass() {}
+    }
+}

core-java-modules/core-java-lang-syntax-2/src/main/java/com/baeldung/core/modifiers/GenericClass.java

@@ -0,0 +1,15 @@
+package com.baeldung.core.modifiers;
+
+public class GenericClass {
+
+    public static void main(String[] args) {
+        // accessing protected constructor
+        FirstClass first = new FirstClass("random name");
+        // using protected method
+        System.out.println("FirstClass name is " + first.getName());
+        // accessing a protected field
+        first.name = "new name";
+        // instantiating protected inner class
+        FirstClass.InnerClass innerClass = new FirstClass.InnerClass();
+    }
+}

core-java-modules/core-java-lang-syntax-2/src/main/java/com/baeldung/core/modifiers/otherpackage/SecondClass.java

@@ -0,0 +1,18 @@
+package com.baeldung.core.modifiers.otherpackage;
+
+import com.baeldung.core.modifiers.FirstClass;
+
+public class SecondClass extends FirstClass {
+    
+    public SecondClass(String name) {
+        // accessing protected constructor
+        super(name);
+        // using protected method
+        System.out.println("SecondClass name is " + this.getName());
+        // accessing a protected field
+        this.name = "new name";
+        // instantiating protected inner class -> add public constructor to InnerClass
+        FirstClass.InnerClass innerClass = new FirstClass.InnerClass();
+    }
+      
+}

core-java-modules/core-java-lang-syntax-2/src/main/java/com/baeldung/core/modifiers/otherpackage/SecondGenericClass.java

@@ -0,0 +1,20 @@
+package com.baeldung.core.modifiers.otherpackage;
+
+import com.baeldung.core.modifiers.FirstClass;
+//import com.baeldung.core.modifiers.FirstClass.InnerClass;
+
+public class SecondGenericClass {
+
+    // uncomment the following lines to see the errors
+    public static void main(String[] args) {
+        // accessing protected constructor
+        // FirstClass first = new FirstClass("random name");
+        // using protected method
+        // System.out.println("FirstClass name is " + first.getName());
+        // accessing a protected field
+        // first.name = "new name";
+        // instantiating protected inner class
+        // FirstClass.InnerClass innerClass = new FirstClass.InnerClass();
+    }
+
+}