update gradle to new version 8.3

- new method 'addChild' to insert a child tree node with a specific given index
- new method 'getChildAt' to get an optional of the child tree node with the given index
- new method 'getChildIndex' to the index from the given child tree node

CHANGELOG.md

@@ -4,7 +4,15 @@
 Version 1.5-SNAPSHOT
 -------------
 
+ADDED:
+
+- new method 'addChild' to insert a child tree node with a specific given index
+- new method 'getChildAt' to get an optional of the child tree node with the given index
+- new method 'getChildIndex' to the index from the given child tree node
+
+CHANGED:
 
+- update gradle to new version 8.3
 
 Version 1.4
 -------------

gradle/wrapper/gradle-wrapper.properties

@@ -1,5 +1,5 @@
 #Wed Feb 19 18:39:09 CET 2020
-distributionUrl=https\://services.gradle.org/distributions/gradle-8.3-rc-4-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-8.3-bin.zip
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
 zipStorePath=wrapper/dists

src/main/java/io/github/astrapi69/tree/api/ITree.java

@@ -27,6 +27,7 @@
 import java.io.Serializable;
 import java.util.Collection;
 import java.util.List;
+import java.util.Optional;
 
 import lombok.NonNull;
 
@@ -49,6 +50,16 @@ public interface ITree<V, T> extends Serializable
 	 */
 	void addChild(final T child);
 
+	/**
+	 * Adds the given child to this tree node
+	 *
+	 * @param child
+	 *            the child
+	 * @param index
+	 *            the index of the child to insert
+	 */
+	void addChild(final T child, int index);
+
 	/**
 	 * Adds all the given children to this tree node
 	 *
@@ -97,6 +108,24 @@ public interface ITree<V, T> extends Serializable
 	 */
 	Collection<T> getChildren();
 
+	/**
+	 * Gets the child tree node from the given index
+	 *
+	 * @param index
+	 *            the index of the child to get
+	 * @return an {@link Optional} object with the child tree node from the given index
+	 */
+	Optional<T> getChildAt(int index);
+
+	/**
+	 * Gets the index of the given child in this tree node
+	 * 
+	 * @param child
+	 *            the child to resolve the index
+	 * @return the index of the given child in this tree node
+	 */
+	int getChildIndex(T child);
+
 	/**
 	 * Sets the children of this tree node
 	 *