diff --git a/abstract-document/README.md b/abstract-document/README.md
index d9538c0bd..bf28ff999 100644
--- a/abstract-document/README.md
+++ b/abstract-document/README.md
@@ -12,15 +12,20 @@ tags:
## Intent
Achieve flexibility of untyped languages and keep the type-safety
-
+
+
+
+
## Applicability
Use the Abstract Document Pattern when
-* there is a need for dynamic properties
-* you want a better way to organize domain
-* you want loosely coupled system with flexibility of untyped languages
+* there is a need to add new properties on the fly
+* you want a flexible way to organize domain in tree like structure
+* you want more loosely coupled system
-## Real world examples
-* [Speedment](https://github.com/speedment/speedment)
\ No newline at end of file
+## Credits
+
+* [Wikipedia: Abstract Document Pattern](https://en.wikipedia.org/wiki/Abstract_Document_Pattern)
+* [Martin Fowler: Dealing with properties](http://martinfowler.com/apsupp/properties.pdf)
\ No newline at end of file
diff --git a/abstract-document/src/main/java/com/iluwatar/abstractdocument/AbstractDocument.java b/abstract-document/src/main/java/com/iluwatar/abstractdocument/AbstractDocument.java
index 054b6ebfb..4bf8f0d14 100644
--- a/abstract-document/src/main/java/com/iluwatar/abstractdocument/AbstractDocument.java
+++ b/abstract-document/src/main/java/com/iluwatar/abstractdocument/AbstractDocument.java
@@ -1,3 +1,25 @@
+/**
+ * The MIT License
+ * Copyright (c) 2014 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.
+ */
package com.iluwatar.abstractdocument;
import java.util.List;
@@ -7,44 +29,44 @@ import java.util.Optional;
import java.util.function.Function;
import java.util.stream.Stream;
+/**
+ * Abstract implementation of Document interface
+ */
public abstract class AbstractDocument implements Document {
- private final Map properties;
+ private final Map properties;
- protected AbstractDocument(Map properties) {
- Objects.requireNonNull(properties, "properties map is required");
- this.properties = properties;
- }
+ protected AbstractDocument(Map properties) {
+ Objects.requireNonNull(properties, "properties map is required");
+ this.properties = properties;
+ }
- @Override
- public Void put(String key, Object value) {
- properties.put(key, value);
- return null;
- }
+ @Override
+ public Void put(String key, Object value) {
+ properties.put(key, value);
+ return null;
+ }
- @Override
- public Object get(String key) {
- return properties.get(key);
- }
+ @Override
+ public Object get(String key) {
+ return properties.get(key);
+ }
- @Override
- public Stream children(String key, Function