feat: Add EntityManager interface and Entity class

database/src/main/java/com/georgev22/library/utilities/Entity.java

@@ -0,0 +1,63 @@
+package com.georgev22.library.utilities;
+
+import com.georgev22.library.maps.ConcurrentObjectMap;
+
+import java.util.UUID;
+
+/**
+ * The {@code Entity} interface represents an entity with a unique identifier.
+ * It provides methods for managing custom data associated with the entity.
+ * Custom data can be added, retrieved, and accessed using key-value pairs.
+ */
+public interface Entity {
+
+    /**
+     * Returns the unique identifier of the entity.
+     *
+     * @return the {@link UUID} representing the entity's ID
+     */
+    UUID getId();
+
+    /**
+     * Adds custom data to the entity with the specified key and value.
+     *
+     * @param key   the key of the custom data
+     * @param value the value of the custom data
+     * @return the updated entity with the added custom data
+     */
+    default Entity addCustomData(String key, Object value) {
+        this.getCustomData().append(key, value);
+        return this;
+    }
+
+    /**
+     * Adds custom data to the entity with the specified key and value if the key does not already exist.
+     *
+     * @param key   the key of the custom data
+     * @param value the value of the custom data
+     * @return the updated entity with the added custom data (if the key did not already exist)
+     */
+    default Entity addCustomDataIfNotExists(String key, Object value) {
+        this.getCustomData().appendIfTrue(key, value, this.getCustomData().containsKey(key));
+        return this;
+    }
+
+    /**
+     * Retrieves the value of the custom data associated with the specified key.
+     *
+     * @param key the key of the custom data
+     * @param <T> the type of the value to retrieve
+     * @return the value associated with the specified key, or {@code null} if the key does not exist
+     */
+    default <T> T getCustomData(String key) {
+        return (T) getCustomData().get(key);
+    }
+
+    /**
+     * Retrieves the map of custom data associated with the entity.
+     *
+     * @return the {@link ConcurrentObjectMap} containing the custom data of the entity
+     */
+    ConcurrentObjectMap<String, Object> getCustomData();
+
+}