Merge pull request #19 from kemitix/upgrade-kemitix-parent-to-2.1.0

Upgrade kemitix-parent to 2.1.0

LICENSE.txt

@@ -1,3 +1,4 @@
+/*
 The MIT License (MIT)
 
 Copyright (c) 2016 Paul Campbell
@@ -19,3 +20,4 @@ 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.
+*/

pom.xml

@@ -11,7 +11,7 @@
     <parent>
         <groupId>net.kemitix</groupId>
         <artifactId>kemitix-parent</artifactId>
-        <version>2.0.0</version>
+        <version>2.1.0</version>
     </parent>
 
     <properties>

src/main/java/net/kemitix/node/AbstractNodeItem.java

@@ -1,3 +1,27 @@
+/*
+The MIT License (MIT)
+
+Copyright (c) 2016 Paul Campbell
+
+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 net.kemitix.node;
 
 import lombok.NonNull;
@@ -11,23 +35,31 @@ import java.util.Set;
  * An abstract node item, providing default implementations for most read-only
  * operations.
  *
- * @author Paul Campbell
- *
  * @param <T> the type of data stored in each node
+ *
+ * @author Paul Campbell (pcampbell@kemitix.net)
  */
 abstract class AbstractNodeItem<T> implements Node<T> {
 
+    private final Set<Node<T>> children;
+
     private T data;
 
     private String name;
 
     private Node<T> parent;
 
-    private final Set<Node<T>> children;
+    /**
-
+     * Constructor.
+     *
+     * @param data     the data of the node
+     * @param name     the name of the node
+     * @param parent   the parent of the node, or null for a root node
+     * @param children the children of the node - must not be null
+     */
     protected AbstractNodeItem(
-            final T data, final String name, final Node<T> parent,
+            final T data, final String name, final Node<T> parent, @NonNull final Set<Node<T>> children
-            final Set<Node<T>> children) {
+                              ) {
         this.data = data;
         this.name = name;
         this.parent = parent;
@@ -68,16 +100,18 @@ abstract class AbstractNodeItem<T> implements Node<T> {
      */
     @Override
     public Optional<Node<T>> findChild(@NonNull final T child) {
-        return children.stream().filter(node -> {
+        return children.stream()
-            final Optional<T> d = node.getData();
+                       .filter(node -> {
-            return d.isPresent() && d.get().equals(child);
+                           final Optional<T> d = node.getData();
-        }).findAny();
+                           return d.isPresent() && d.get()
+                                                    .equals(child);
+                       })
+                       .findAny();
     }
 
     @Override
     public Node<T> getChild(final T child) {
-        return findChild(child).orElseThrow(
+        return findChild(child).orElseThrow(() -> new NodeException("Child not found"));
-                () -> new NodeException("Child not found"));
     }
 
     /**
@@ -89,8 +123,7 @@ abstract class AbstractNodeItem<T> implements Node<T> {
      */
     @Override
     public boolean isDescendantOf(final Node<T> node) {
-        return parent != null && (node.equals(parent) || parent.isDescendantOf(
+        return parent != null && (node.equals(parent) || parent.isDescendantOf(node));
-                node));
     }
 
     /**
@@ -106,14 +139,9 @@ abstract class AbstractNodeItem<T> implements Node<T> {
             return Optional.empty();
         }
         Node<T> current = this;
-        for (T item : path) {
+        for (int i = 0, pathSize = path.size(); i < pathSize && current != null; i++) {
-            final Optional<Node<T>> child = current.findChild(item);
+            current = current.findChild(path.get(i))
-            if (child.isPresent()) {
+                             .orElse(null);
-                current = child.get();
-            } else {
-                current = null;
-                break;
-            }
         }
         return Optional.ofNullable(current);
     }
@@ -121,14 +149,14 @@ abstract class AbstractNodeItem<T> implements Node<T> {
     @Override
     public Optional<Node<T>> findChildByName(@NonNull final String named) {
         return children.stream()
-                       .filter(n -> n.getName().equals(named))
+                       .filter(n -> n.getName()
+                                     .equals(named))
                        .findAny();
     }
 
     @Override
     public Node<T> getChildByName(final String named) {
-        return findChildByName(named).orElseThrow(
+        return findChildByName(named).orElseThrow(() -> new NodeException("Named child not found"));
-                () -> new NodeException("Named child not found"));
     }
 
     @Override

src/main/java/net/kemitix/node/ImmutableNodeItem.java

@@ -1,3 +1,27 @@
+/*
+The MIT License (MIT)
+
+Copyright (c) 2016 Paul Campbell
+
+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 net.kemitix.node;
 
 import java.util.List;
@@ -11,28 +35,50 @@ import java.util.Set;
  * getData()} they could then modify the original data within the node. This
  * wouldn't affect the integrity of the node tree structure, however.</p>
  *
- * @author Paul Campbell
- *
  * @param <T> the type of data stored in each node
+ *
+ * @author Paul Campbell (pcampbell@kemitix.net)
  */
 final class ImmutableNodeItem<T> extends AbstractNodeItem<T> {
 
     private static final String IMMUTABLE_OBJECT = "Immutable object";
 
     private ImmutableNodeItem(
-            final T data, final String name, final Node<T> parent,
+            final T data, final String name, final Node<T> parent, final Set<Node<T>> children
-            final Set<Node<T>> children) {
+                             ) {
         super(data, name, parent, children);
     }
 
+    /**
+     * Creates a new immutable root node.
+     *
+     * @param data     the data of the node
+     * @param name     the name of the node
+     * @param children the children of the node
+     * @param <T>      the type of the data in the node
+     *
+     * @return the new node tree's root node
+     */
     static <T> ImmutableNodeItem<T> newRoot(
-            final T data, final String name, final Set<Node<T>> children) {
+            final T data, final String name, final Set<Node<T>> children
+                                           ) {
         return new ImmutableNodeItem<>(data, name, null, children);
     }
 
+    /**
+     * Creates a new immutable subtree from this child.
+     *
+     * @param data     the data of the node
+     * @param name     the name of the node
+     * @param parent   the mutable parent of the node
+     * @param children the children of the node
+     * @param <T>      the type of the data in the node
+     *
+     * @return the new immutable node
+     */
     static <T> ImmutableNodeItem<T> newChild(
-            final T data, final String name, final Node<T> parent,
+            final T data, final String name, final Node<T> parent, final Set<Node<T>> children
-            final Set<Node<T>> children) {
+                                            ) {
         return new ImmutableNodeItem<>(data, name, parent, children);
     }
 
@@ -73,8 +119,7 @@ final class ImmutableNodeItem<T> extends AbstractNodeItem<T> {
 
     @Override
     public Node<T> findOrCreateChild(final T child) {
-        return findChild(child).orElseThrow(
+        return findChild(child).orElseThrow(() -> new UnsupportedOperationException(IMMUTABLE_OBJECT));
-                () -> new UnsupportedOperationException(IMMUTABLE_OBJECT));
     }
 
     @Override

src/main/java/net/kemitix/node/Node.java

@@ -1,3 +1,27 @@
+/*
+The MIT License (MIT)
+
+Copyright (c) 2016 Paul Campbell
+
+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 net.kemitix.node;
 
 import java.util.List;
@@ -7,9 +31,9 @@ import java.util.Set;
 /**
  * An interface for tree node items.
  *
- * @author Paul Campbell
- *
  * @param <T> the type of data held in each node
+ *
+ * @author Paul Campbell (pcampbell@kemitix.net)
  */
 public interface Node<T> {
 
@@ -32,8 +56,7 @@ public interface Node<T> {
     /**
      * Fetch the data held within the node.
      *
-     * @return an Optional containing the node's data, or empty if the node has
+     * @return an Optional containing the node's data, or empty if the node has none
-     * none
      */
     Optional<T> getData();
 
@@ -114,8 +137,7 @@ public interface Node<T> {
      *
      * @return the found or created child node
      *
-     * @deprecated use {@code node.findChild(child).orElseGet(() ->
+     * @deprecated use {@code node.findChild(child).orElseGet(() -> node.createChild(child))};
-     * node.createChild(child))};
      */
     @Deprecated
     Node<T> findOrCreateChild(T child);
@@ -135,8 +157,6 @@ public interface Node<T> {
      * @param child the child's data to search for
      *
      * @return the child node if found
-     *
-     * @throws NodeException if the node is not found
      */
     Node<T> getChild(T child);
 
@@ -183,8 +203,6 @@ public interface Node<T> {
      * @param name the name of the child
      *
      * @return the node
-     *
-     * @throws NodeException if the node is not found
      */
     Node<T> getChildByName(String name);
 

src/main/java/net/kemitix/node/NodeException.java

@@ -1,9 +1,33 @@
+/*
+The MIT License (MIT)
+
+Copyright (c) 2016 Paul Campbell
+
+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 net.kemitix.node;
 
 /**
  * Represents an error within the tree node.
  *
- * @author pcampbell
+ * @author Paul Campbell (pcampbell@kemitix.net)
  */
 @SuppressWarnings("serial")
 public class NodeException extends RuntimeException {

src/main/java/net/kemitix/node/NodeItem.java

@@ -1,3 +1,27 @@
+/*
+The MIT License (MIT)
+
+Copyright (c) 2016 Paul Campbell
+
+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 net.kemitix.node;
 
 import lombok.NonNull;
@@ -12,16 +36,16 @@ import java.util.Set;
 /**
  * Represents a tree of nodes.
  *
- * @author Paul Campbell
- *
  * @param <T> the type of data stored in each node
+ *
+ * @author Paul Campbell (pcampbell@kemitix.net)
  */
 class NodeItem<T> implements Node<T> {
 
-    private T data;
-
     private final Set<Node<T>> children = new HashSet<>();
 
+    private T data;
+
     private Node<T> parent;
 
     private String name;
@@ -100,6 +124,24 @@ class NodeItem<T> implements Node<T> {
         return Optional.ofNullable(parent);
     }
 
+    /**
+     * Make the current node a direct child of the parent.
+     *
+     * @param parent the new parent node
+     */
+    @Override
+    public final void setParent(@NonNull final Node<T> parent) {
+        if (this.equals(parent) || parent.isDescendantOf(this)) {
+            throw new NodeException("Parent is a descendant");
+        }
+        if (this.parent != null) {
+            this.parent.getChildren()
+                       .remove(this);
+        }
+        this.parent = parent;
+        parent.addChild(this);
+    }
+
     @Override
     public Set<Node<T>> getChildren() {
         return children;
@@ -117,20 +159,20 @@ class NodeItem<T> implements Node<T> {
         children.add(child);
         // update the child's parent if they don't have one or it is not this
         val childParent = child.getParent();
-        if (!childParent.isPresent() || !childParent.get().equals(this)) {
+        if (!childParent.isPresent() || !childParent.get()
+                                                    .equals(this)) {
             child.setParent(this);
         }
     }
 
     private void verifyChildWithSameNameDoesNotAlreadyExist(
-            final @NonNull Node<T> child) {
+            final @NonNull Node<T> child
+                                                           ) {
         if (child.isNamed()) {
-            findChildByName(child.getName())
+            findChildByName(child.getName()).filter(existingChild -> existingChild != child)
-                    .filter(existingChild -> existingChild != child)
+                                            .ifPresent(existingChild -> {
-                    .ifPresent(existingChild -> {
+                                                throw new NodeException("Node with that name already exists here");
-                        throw new NodeException(
+                                            });
-                                "Node with that name already exists here");
-                    });
         }
     }
 
@@ -169,8 +211,7 @@ class NodeItem<T> implements Node<T> {
     @Override
     public void createDescendantLine(@NonNull final List<T> descendants) {
         if (!descendants.isEmpty()) {
-            findOrCreateChild(descendants.get(0)).createDescendantLine(
+            findOrCreateChild(descendants.get(0)).createDescendantLine(descendants.subList(1, descendants.size()));
-                    descendants.subList(1, descendants.size()));
         }
     }
 
@@ -182,8 +223,7 @@ class NodeItem<T> implements Node<T> {
      *
      * @return the found or created child node
      *
-     * @deprecated use node.findChild(child).orElseGet(() -> node.createChild
+     * @deprecated use node.findChild(child).orElseGet(() -> node.createChild (child));
-     * (child));
      */
     @Override
     @Deprecated
@@ -200,10 +240,13 @@ class NodeItem<T> implements Node<T> {
      */
     @Override
     public Optional<Node<T>> findChild(@NonNull final T child) {
-        return children.stream().filter(node -> {
+        return children.stream()
-            final Optional<T> d = node.getData();
+                       .filter(node -> {
-            return d.isPresent() && d.get().equals(child);
+                           final Optional<T> d = node.getData();
-        }).findAny();
+                           return d.isPresent() && d.get()
+                                                    .equals(child);
+                       })
+                       .findAny();
     }
 
     @Override
@@ -224,25 +267,7 @@ class NodeItem<T> implements Node<T> {
      */
     @Override
     public boolean isDescendantOf(final Node<T> node) {
-        return parent != null && (node.equals(parent) || parent.isDescendantOf(
+        return parent != null && (node.equals(parent) || parent.isDescendantOf(node));
-                node));
-    }
-
-    /**
-     * Make the current node a direct child of the parent.
-     *
-     * @param parent the new parent node
-     */
-    @Override
-    public final void setParent(@NonNull final Node<T> parent) {
-        if (this.equals(parent) || parent.isDescendantOf(this)) {
-            throw new NodeException("Parent is a descendant");
-        }
-        if (this.parent != null) {
-            this.parent.getChildren().remove(this);
-        }
-        this.parent = parent;
-        parent.addChild(this);
     }
 
     /**
@@ -258,14 +283,9 @@ class NodeItem<T> implements Node<T> {
             return Optional.empty();
         }
         Node<T> current = this;
-        for (T item : path) {
+        for (int i = 0, pathSize = path.size(); i < pathSize && current != null; i++) {
-            final Optional<Node<T>> child = current.findChild(item);
+            current = current.findChild(path.get(i))
-            if (child.isPresent()) {
+                             .orElse(null);
-                current = child.get();
-            } else {
-                current = null;
-                break;
-            }
         }
         return Optional.ofNullable(current);
     }
@@ -276,10 +296,8 @@ class NodeItem<T> implements Node<T> {
             insertChild(nodeItem);
         } else {
             val item = path[0];
-            findChildByName(item)
+            findChildByName(item).orElseGet(() -> new NodeItem<>(null, item, this))
-                    .orElseGet(() -> new NodeItem<>(null, item, this))
+                                 .insertInPath(nodeItem, Arrays.copyOfRange(path, 1, path.length));
-                    .insertInPath(nodeItem,
-                            Arrays.copyOfRange(path, 1, path.length));
         }
     }
 
@@ -299,10 +317,10 @@ class NodeItem<T> implements Node<T> {
             val existing = childByName.get();
             if (existing.isEmpty()) {
                 // place any data in the new node into the existing empty node
-                nodeItem.getData().ifPresent(existing::setData);
+                nodeItem.getData()
+                        .ifPresent(existing::setData);
             } else {
-                throw new NodeException("A non-empty node named '"
+                throw new NodeException("A non-empty node named '" + nodeItem.getName() + "' already exists here");
-                        + nodeItem.getName() + "' already exists here");
             }
         } else {
             // nothing with the same name exists
@@ -313,8 +331,9 @@ class NodeItem<T> implements Node<T> {
     @Override
     public Optional<Node<T>> findChildByName(@NonNull final String named) {
         return children.stream()
-                .filter((Node<T> t) -> t.getName().equals(named))
+                       .filter((Node<T> t) -> t.getName()
-                .findAny();
+                                               .equals(named))
+                       .findAny();
     }
 
     @Override

src/main/java/net/kemitix/node/Nodes.java

@@ -1,3 +1,27 @@
+/*
+The MIT License (MIT)
+
+Copyright (c) 2016 Paul Campbell
+
+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 net.kemitix.node;
 
 import java.util.Optional;
@@ -7,7 +31,7 @@ import java.util.stream.Collectors;
 /**
  * Utility class for {@link Node} items.
  *
- * @author pcampbell
+ * @author Paul Campbell (pcampbell@kemitix.net)
  */
 public final class Nodes {
 
@@ -63,7 +87,8 @@ public final class Nodes {
      * @return the new node
      */
     public static <T> Node<T> namedChild(
-            final T data, final String name, final Node<T> parent) {
+            final T data, final String name, final Node<T> parent
+                                        ) {
         return new NodeItem<>(data, name, parent);
     }
 
@@ -76,12 +101,13 @@ public final class Nodes {
      * @return the immutable copy of the tree
      */
     public static <T> Node<T> asImmutable(final Node<T> root) {
-        if (root.getParent().isPresent()) {
+        if (root.getParent()
+                .isPresent()) {
             throw new IllegalArgumentException("source must be the root node");
         }
         final Set<Node<T>> children = getImmutableChildren(root);
-        return ImmutableNodeItem.newRoot(root.getData().orElse(null),
+        return ImmutableNodeItem.newRoot(root.getData()
-                root.getName(), children);
+                                             .orElse(null), root.getName(), children);
     }
 
     private static <T> Set<Node<T>> getImmutableChildren(final Node<T> source) {
@@ -92,15 +118,16 @@ public final class Nodes {
     }
 
     private static <T> Node<T> asImmutableChild(
-            final Node<T> source) {
+            final Node<T> source
+                                               ) {
         final Optional<Node<T>> sourceParent = source.getParent();
         if (sourceParent.isPresent()) {
-            return ImmutableNodeItem.newChild(source.getData().orElse(null),
+            return ImmutableNodeItem.newChild(source.getData()
-                    source.getName(), sourceParent.get(),
+                                                    .orElse(null), source.getName(), sourceParent.get(),
-                    getImmutableChildren(source));
+                                              getImmutableChildren(source)
+                                             );
         } else {
-            throw new IllegalArgumentException(
+            throw new IllegalArgumentException("source must not be the root node");
-                    "source must not be the root node");
         }
     }
 

src/main/java/net/kemitix/node/package-info.java

@@ -1,4 +1,28 @@
+/*
+The MIT License (MIT)
+
+Copyright (c) 2016 Paul Campbell
+
+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.
+*/
 /**
  * Tree Node implementation.
  */
+
 package net.kemitix.node;