MySQL and Flatfile databases now store and retrieve objects.

src/main/java/us/tastybento/bskyblock/BSkyBlock.java

@@ -2,6 +2,7 @@ package us.tastybento.bskyblock;
 
 import java.util.HashMap;
 import java.util.HashSet;
+import java.util.Map.Entry;
 import java.util.Set;
 import java.util.UUID;
 
@@ -14,7 +15,6 @@ import us.tastybento.bskyblock.config.BSBLocale;
 import us.tastybento.bskyblock.config.PluginConfig;
 import us.tastybento.bskyblock.config.Settings;
 import us.tastybento.bskyblock.database.BSBDatabase;
-import us.tastybento.bskyblock.database.BSBDatabase.DatabaseType;
 import us.tastybento.bskyblock.database.managers.IslandsManager;
 import us.tastybento.bskyblock.database.managers.OfflineHistoryMessages;
 import us.tastybento.bskyblock.database.managers.PlayersManager;
@@ -83,6 +83,7 @@ public class BSkyBlock extends JavaPlugin{
 
                     // Test: Create a random island and save it
                     // TODO: ideally this should be in a test class!
+                    /*
                     UUID owner = UUID.fromString("ddf561c5-72b6-4ec6-a7ea-8b50a893beb2");
                     
                     Island island = islandsManager.createIsland(new Location(getServer().getWorld("world"),0,0,0,0,0), owner);
@@ -109,17 +110,21 @@ public class BSkyBlock extends JavaPlugin{
                     
                     getLogger().info("DEBUG: ************ Finished saving, now loading *************");
                     
-                     
+                     */
                     
                     playersManager.load();
                     islandsManager.load();
-
+                    /*
+                     *DEBUG CODE
                     Island loadedIsland = islandsManager.getIsland(owner);
                     getLogger().info("Island name = " + loadedIsland.getName());
                     getLogger().info("Island locked = " + loadedIsland.getLocked());
                     //getLogger().info("Random set = " + randomSet);
                     getLogger().info("Island coops = " + loadedIsland.getCoops());
-
+                    for (Entry<SettingsFlag, Boolean> flag: loadedIsland.getFlags().entrySet()) {
+                        getLogger().info("Flag " + flag.getKey().name() + " = " + flag.getValue());
+                    }
+                    */
                     // Save islands & players data asynchronously every X minutes
                     Settings.databaseBackupPeriod = 10 * 60 * 20;
                     plugin.getServer().getScheduler().runTaskTimer(plugin, new Runnable() {

src/main/java/us/tastybento/bskyblock/database/flatfile/FlatFileDatabaseHandler.java

@@ -7,18 +7,24 @@ import java.io.FilenameFilter;
 import java.lang.reflect.Field;
 import java.lang.reflect.InvocationTargetException;
 import java.lang.reflect.Method;
+import java.lang.reflect.Type;
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.HashSet;
 import java.util.List;
+import java.util.Map;
+import java.util.Map.Entry;
 import java.util.Set;
 import java.util.UUID;
 
+import org.bukkit.Location;
+import org.bukkit.World;
 import org.bukkit.configuration.file.YamlConfiguration;
 
 import us.tastybento.bskyblock.BSkyBlock;
 import us.tastybento.bskyblock.database.DatabaseConnecter;
 import us.tastybento.bskyblock.database.managers.AbstractDatabaseHandler;
+import us.tastybento.bskyblock.util.Util;
 
 /**
  * Class that creates a list of <T>s filled with values from the corresponding
@@ -53,9 +59,10 @@ public class FlatFileDatabaseHandler<T> extends AbstractDatabaseHandler<T> {
      * @throws IllegalArgumentException 
      * @throws IllegalAccessException 
      * @throws InstantiationException 
+     * @throws ClassNotFoundException 
      */
     @Override
-    public T selectObject(String key) throws InstantiationException, IllegalAccessException, IllegalArgumentException, InvocationTargetException, IntrospectionException  {
+    public T selectObject(String key) throws InstantiationException, IllegalAccessException, IllegalArgumentException, InvocationTargetException, IntrospectionException, ClassNotFoundException  {
         YamlConfiguration config = databaseConnecter.loadYamlFile(type.getSimpleName(), key);
         return createObject(config);
     }
@@ -68,9 +75,10 @@ public class FlatFileDatabaseHandler<T> extends AbstractDatabaseHandler<T> {
      * @throws IllegalArgumentException
      * @throws InvocationTargetException
      * @throws IntrospectionException
+     * @throws ClassNotFoundException 
      */
     @Override
-    public List<T> selectObjects() throws InstantiationException, IllegalAccessException, IllegalArgumentException, InvocationTargetException, IntrospectionException {
+    public List<T> selectObjects() throws InstantiationException, IllegalAccessException, IllegalArgumentException, InvocationTargetException, IntrospectionException, ClassNotFoundException {
         List<T> list = new ArrayList<T>();
         FilenameFilter ymlFilter = new FilenameFilter() {
             @Override
@@ -108,49 +116,73 @@ public class FlatFileDatabaseHandler<T> extends AbstractDatabaseHandler<T> {
      * @throws IntrospectionException
      * @throws IllegalArgumentException
      * @throws InvocationTargetException
+     * @throws ClassNotFoundException 
      */
-    private T createObject(YamlConfiguration config) throws InstantiationException, IllegalAccessException, IntrospectionException, IllegalArgumentException, InvocationTargetException {
+    private T createObject(YamlConfiguration config) throws InstantiationException, IllegalAccessException, IntrospectionException, IllegalArgumentException, InvocationTargetException, ClassNotFoundException {
         T instance = type.newInstance();
 
         for (Field field : type.getDeclaredFields()) {
 
-            /* We assume the table-column-names exactly match the variable-names of T */
+            PropertyDescriptor propertyDescriptor = new PropertyDescriptor(field.getName(), type);
-            // TODO: depending on the data type, it'll need deserializing
+            Method method = propertyDescriptor.getWriteMethod();
-            try {
+            //plugin.getLogger().info("DEBUG: " + field.getName() + ": " + propertyDescriptor.getPropertyType().getTypeName());
+            if (propertyDescriptor.getPropertyType().equals(HashMap.class)) {
 
-                PropertyDescriptor propertyDescriptor = new PropertyDescriptor(field.getName(), type);
+                // Note that we have no idea what type this is
-                Method method = propertyDescriptor.getWriteMethod();
+                List<Type> collectionTypes = Util.getCollectionParameterTypes(method);
-                plugin.getLogger().info("DEBUG: " + field.getName() + ": " + propertyDescriptor.getPropertyType().getTypeName());
+                // collectionTypes should be 2 long
-                if (propertyDescriptor.getPropertyType().equals(HashMap.class)) {
+                Type keyType = collectionTypes.get(0);
-                    plugin.getLogger().info("DEBUG: is HashMap");
+                Type valueType = collectionTypes.get(1);
-                    // TODO: this may not work with all keys. Further serialization may be required.
+                //plugin.getLogger().info("DEBUG: is HashMap<" + keyType.getTypeName() + ", " + valueType.getTypeName() + ">");
-                    HashMap<Object,Object> value = new HashMap<Object, Object>();
+                // TODO: this may not work with all keys. Further serialization may be required.
-                    for (String key : config.getConfigurationSection(field.getName()).getKeys(false)) {
+                HashMap<Object,Object> value = new HashMap<Object, Object>();
-                        value.put(key, config.get(field.getName() + "." + key));
+                for (String key : config.getConfigurationSection(field.getName()).getKeys(false)) {
-                    }
+                    Object mapKey = deserialize(key,Class.forName(keyType.getTypeName()));
-                    method.invoke(instance, value);
+                    Object mapValue = deserialize(config.get(field.getName() + "." + key), Class.forName(valueType.getTypeName()));
-                } else if (propertyDescriptor.getPropertyType().equals(Set.class)) {
+                    value.put(mapKey, mapValue);
-                    plugin.getLogger().info("DEBUG: is Set " + propertyDescriptor.getReadMethod().getGenericReturnType().getTypeName());
-
-                    // TODO: this may not work with all keys. Further serialization may be required.
-                    Set<Object> value = new HashSet((List<Object>) config.getList(field.getName()));
-                    
-                    method.invoke(instance, value);
-                } else if (propertyDescriptor.getPropertyType().equals(UUID.class)) {
-                    plugin.getLogger().info("DEBUG: is UUID");
-                    String uuid = (String)config.get(field.getName());
-                    if (uuid == null || uuid.equals("null")) {
-                        method.invoke(instance, (Object)null); 
-                    } else {
-                        Object value = UUID.fromString(uuid);
-                        method.invoke(instance, value);
-                    }
-                } else {
-                    Object value = config.get(field.getName());
-                    method.invoke(instance, value);
                 }
-            } catch (Exception e) {
+                method.invoke(instance, value);
-                e.printStackTrace();
+            } else if (propertyDescriptor.getPropertyType().equals(Set.class)) {
+                //plugin.getLogger().info("DEBUG: is Set " + propertyDescriptor.getReadMethod().getGenericReturnType().getTypeName());
+                //plugin.getLogger().info("DEBUG: adding a set");
+                // Loop through the collection resultset 
+                // Note that we have no idea what type this is
+                List<Type> collectionTypes = Util.getCollectionParameterTypes(method);
+                // collectionTypes should be only 1 long
+                Type setType = collectionTypes.get(0);
+                //plugin.getLogger().info("DEBUG: is HashSet<" + setType.getTypeName() + ">");
+                Set<Object> value = new HashSet<Object>();
+                //plugin.getLogger().info("DEBUG: collection type argument = " + collectionTypes);
+                //plugin.getLogger().info("DEBUG: setType = " + setType.getTypeName());
+                for (Object listValue: config.getList(field.getName())) {
+                    //plugin.getLogger().info("DEBUG: collectionResultSet size = " + collectionResultSet.getFetchSize());
+                    ((Set<Object>) value).add(deserialize(listValue,Class.forName(setType.getTypeName())));
+                }
+                // TODO: this may not work with all keys. Further serialization may be required.
+                //Set<Object> value = new HashSet((List<Object>) config.getList(field.getName()));                    
+                method.invoke(instance, value);
+            } else if (propertyDescriptor.getPropertyType().equals(ArrayList.class)) {
+                //plugin.getLogger().info("DEBUG: is Set " + propertyDescriptor.getReadMethod().getGenericReturnType().getTypeName());
+                //plugin.getLogger().info("DEBUG: adding a set");
+                // Loop through the collection resultset 
+                // Note that we have no idea what type this is
+                List<Type> collectionTypes = Util.getCollectionParameterTypes(method);
+                // collectionTypes should be only 1 long
+                Type setType = collectionTypes.get(0);
+                List<Object> value = new ArrayList<Object>();
+                //plugin.getLogger().info("DEBUG: collection type argument = " + collectionTypes);
+                //plugin.getLogger().info("DEBUG: setType = " + setType.getTypeName());
+                for (Object listValue: config.getList(field.getName())) {
+                    //plugin.getLogger().info("DEBUG: collectionResultSet size = " + collectionResultSet.getFetchSize());
+                    ((List<Object>) value).add(deserialize(listValue,Class.forName(setType.getTypeName())));
+                }
+                // TODO: this may not work with all keys. Further serialization may be required.
+                //Set<Object> value = new HashSet((List<Object>) config.getList(field.getName()));                    
+                method.invoke(instance, value);
+            } else {
+                // Not a collection
+                Object value = config.get(field.getName());
+                method.invoke(instance, deserialize(value,propertyDescriptor.getPropertyType()));
             }
 
         }
@@ -182,8 +214,8 @@ public class FlatFileDatabaseHandler<T> extends AbstractDatabaseHandler<T> {
             Method method = propertyDescriptor.getReadMethod();
             // Invoke the read method to get the value. We have no idea what type of value it is.
             Object value = method.invoke(instance);
-            plugin.getLogger().info("DEBUG: writing " + field.getName());
+            //plugin.getLogger().info("DEBUG: writing " + field.getName());
-            plugin.getLogger().info("DEBUG: property desc = " + propertyDescriptor.getPropertyType().getTypeName());
+            //plugin.getLogger().info("DEBUG: property desc = " + propertyDescriptor.getPropertyType().getTypeName());
             // Depending on the vale type, it'll need serializing differenty
             // Check if this field is the mandatory UniqueId field. This is used to identify this instantiation of the class
             if (method.getName().equals("getUniqueId")) {
@@ -199,36 +231,98 @@ public class FlatFileDatabaseHandler<T> extends AbstractDatabaseHandler<T> {
                 filename = id;
             }
             // UUID's need special serialization
-            if (propertyDescriptor.getPropertyType().equals(UUID.class)) {
+            if (propertyDescriptor.getPropertyType().equals(HashMap.class) || propertyDescriptor.getPropertyType().equals(Map.class)) {
-                plugin.getLogger().info("DEBUG: writing UUID for " + field.getName());
+                // Maps need to have keys serialized
-                if (value != null) {
+                //plugin.getLogger().info("DEBUG: Map for " + field.getName());
-                    config.set(field.getName(), ((UUID)value).toString());
+                Map<Object, Object> result = new HashMap<Object, Object>();
-                } else {
+                for (Entry<Object, Object> object : ((Map<Object,Object>)value).entrySet()) {
-                    // UUID's can be null, so they need to be saved as the string "null"
+                    // Serialize all key types
-                    config.set(field.getName(), "null");
+                    // TODO: also need to serialize values?
+                    result.put(serialize(object.getKey()), object.getValue());
                 }
+                // Save the list in the config file
+                config.set(field.getName(), result);
             } else if (propertyDescriptor.getPropertyType().equals(Set.class)) {
                 // Sets need to be serialized as string lists
-                plugin.getLogger().info("DEBUG: Set for " + field.getName());
+                //plugin.getLogger().info("DEBUG: Set for " + field.getName());
-
                 List<Object> list = new ArrayList<Object>();
                 for (Object object : (Set<Object>)value) {
-                    if (object instanceof UUID) {
+                    list.add(serialize(object));
-                        list.add(((UUID)object).toString());
-                    }
                 }
                 // Save the list in the config file
                 config.set(field.getName(), list);
             } else {
                 // For all other data that doesn't need special serialization
-                config.set(field.getName(), value);
+                config.set(field.getName(), serialize(value));
             }
         }
         if (filename.isEmpty()) {
-            throw new IllegalArgumentException("No UUID in class");
+            throw new IllegalArgumentException("No uniqueId in class");
         }
         // Save the file in the right folder
         databaseConnecter.saveYamlFile(config, type.getSimpleName(), filename);
 
     }
+
+    /**
+     * Serialize an object if required
+     * @param object
+     * @return
+     */
+    private Object serialize(Object object) {
+        if (object == null) {
+            return "null";
+        }
+        //plugin.getLogger().info("DEBUG: serializing " + object.getClass().getTypeName());
+        if (object instanceof UUID) {
+            return ((UUID)object).toString();
+        }
+        if (object instanceof World) {
+            return ((World)object).getName();
+        }
+        if (object instanceof Location) {
+            return Util.getStringLocation((Location)object);
+        }
+        if (object instanceof Enum) {
+            //Custom enums are a child of the Enum class. Just get the names of each one.
+            return ((Enum<?>)object).name();
+        }
+        return object;
+    }
+
+    private Object deserialize(Object value, Class<? extends Object> clazz) { 
+        //plugin.getLogger().info("DEBUG: deserialize - class is " + clazz.getCanonicalName());
+        if (value instanceof String && value.equals("null")) {
+            // If the value is null as a string, return null 
+            return null;
+        }
+        // Types that need to be deserialized
+        if (clazz.equals(UUID.class)) {
+            value = UUID.fromString((String)value);
+        }
+        // Bukkit Types
+        if (clazz.equals(Location.class)) {
+            // Get Location from String - may be null...
+            value = Util.getLocationString(((String)value));
+        }
+        if (clazz.equals(World.class)) {
+            // Get world by name - may be null...
+            value = plugin.getServer().getWorld((String)value);
+        }
+        // Enums
+        if (clazz.getSuperclass() != null && clazz.getSuperclass().equals(Enum.class)) {
+            //Custom enums are a child of the Enum class.
+            // Find out the value
+            try {
+                Class<Enum> enumClass = (Class<Enum>)clazz;
+                value = Enum.valueOf(enumClass, (String)value);
+            } catch (Exception e) {
+                // Maybe this value does not exist?
+                // TODO return something?
+                e.printStackTrace();
+            }
+        }
+        return value;
+    }
+
 }

src/main/java/us/tastybento/bskyblock/database/managers/AbstractDatabaseHandler.java

@@ -108,8 +108,9 @@ public abstract class AbstractDatabaseHandler<T> {
      * @throws IntrospectionException
      * @throws SecurityException 
      * @throws SQLException 
+     * @throws ClassNotFoundException 
      */
-    protected abstract List<T> selectObjects() throws InstantiationException, IllegalAccessException, IllegalArgumentException, InvocationTargetException, IntrospectionException, SQLException, SecurityException;
+    protected abstract List<T> selectObjects() throws InstantiationException, IllegalAccessException, IllegalArgumentException, InvocationTargetException, IntrospectionException, SQLException, SecurityException, ClassNotFoundException;
 
     /**
      * Creates a <T> filled with values from the corresponding
@@ -122,8 +123,10 @@ public abstract class AbstractDatabaseHandler<T> {
      * @throws IllegalAccessException 
      * @throws InstantiationException 
      * @throws SQLException 
+     * @throws ClassNotFoundException 
+     * @throws SecurityException 
      */
-    protected abstract T selectObject(String uniqueId) throws InstantiationException, IllegalAccessException, IllegalArgumentException, InvocationTargetException, IntrospectionException, SQLException;
+    protected abstract T selectObject(String uniqueId) throws InstantiationException, IllegalAccessException, IllegalArgumentException, InvocationTargetException, IntrospectionException, SQLException, SecurityException, ClassNotFoundException;
 
     /**
      * Inserts T into the corresponding database-table

src/main/java/us/tastybento/bskyblock/database/mysql/MySQLDatabaseHandler.java

@@ -249,29 +249,6 @@ public class MySQLDatabaseHandler<T> extends AbstractDatabaseHandler<T> {
         return columns;
     }
 
-    /**
-     * Get a list of parameter types for the collection argument in this method
-     * @param writeMethod
-     * @return
-     */
-    private List<Type> getCollectionParameterTypes(Method writeMethod) {
-        List<Type> result = new ArrayList<Type>();
-        // Get the return type
-        // This uses a trick to extract what the arguments are of the writeMethod of the field.
-        // In this way, we can deduce what type needs to be written at runtime.
-        Type[] genericParameterTypes = writeMethod.getGenericParameterTypes();
-        // There could be more than one argument, so step through them
-        for (int i = 0; i < genericParameterTypes.length; i++) {
-            // If the argument is a parameter, then do something - this should always be true if the parameter is a collection
-            if( genericParameterTypes[i] instanceof ParameterizedType ) {
-                // Get the actual type arguments of the parameter 
-                Type[] parameters = ((ParameterizedType)genericParameterTypes[i]).getActualTypeArguments();
-                result.addAll(Arrays.asList(parameters));
-            }
-        }
-        return result;
-    }
-
 
     /* (non-Javadoc)
      * @see us.tastybento.bskyblock.database.managers.AbstractDatabaseHandler#createSelectQuery()
@@ -504,12 +481,13 @@ public class MySQLDatabaseHandler<T> extends AbstractDatabaseHandler<T> {
      * @throws IllegalAccessException
      * @throws IntrospectionException
      * @throws InvocationTargetException
+     * @throws ClassNotFoundException 
      */
     @Override
     public List<T> selectObjects() throws SQLException,
     SecurityException, IllegalArgumentException,
     InstantiationException, IllegalAccessException,
-    IntrospectionException, InvocationTargetException {
+    IntrospectionException, InvocationTargetException, ClassNotFoundException {
 
         Connection connection = null;
         Statement statement = null;
@@ -535,7 +513,7 @@ public class MySQLDatabaseHandler<T> extends AbstractDatabaseHandler<T> {
     @Override
     protected T selectObject(String uniqueId) throws InstantiationException,
     IllegalAccessException, IllegalArgumentException,
-    InvocationTargetException, IntrospectionException, SQLException {
+    InvocationTargetException, IntrospectionException, SQLException, SecurityException, ClassNotFoundException {
         Connection connection = null;
         Statement statement = null;
         ResultSet resultSet = null;
@@ -578,13 +556,14 @@ public class MySQLDatabaseHandler<T> extends AbstractDatabaseHandler<T> {
      * @throws IllegalAccessException
      * @throws IntrospectionException
      * @throws InvocationTargetException
+     * @throws ClassNotFoundException 
      */
     @SuppressWarnings("unchecked")
     private List<T> createObjects(ResultSet resultSet)
             throws SecurityException, IllegalArgumentException,
             SQLException, InstantiationException,
             IllegalAccessException, IntrospectionException,
-            InvocationTargetException {
+            InvocationTargetException, ClassNotFoundException {
 
         List<T> list = new ArrayList<T>();
         // The database can return multiple results in one go, e.g., all the islands in the database
@@ -633,7 +612,7 @@ public class MySQLDatabaseHandler<T> extends AbstractDatabaseHandler<T> {
                         //plugin.getLogger().info("DEBUG: adding a set");
                         // Loop through the collection resultset 
                         // Note that we have no idea what type this is
-                        List<Type> collectionTypes = getCollectionParameterTypes(method);
+                        List<Type> collectionTypes = Util.getCollectionParameterTypes(method);
                         // collectionTypes should be only 1 long
                         Type setType = collectionTypes.get(0);
                         value = new HashSet<Object>();
@@ -641,13 +620,13 @@ public class MySQLDatabaseHandler<T> extends AbstractDatabaseHandler<T> {
                         //plugin.getLogger().info("DEBUG: setType = " + setType.getTypeName());
                         while (collectionResultSet.next()) {
                             //plugin.getLogger().info("DEBUG: collectionResultSet size = " + collectionResultSet.getFetchSize());
-                            ((Set<Object>) value).add(deserialize(collectionResultSet.getObject(1),setType.getClass()));
+                            ((Set<Object>) value).add(deserialize(collectionResultSet.getObject(1),Class.forName(setType.getTypeName())));
                         }
                     } else if (propertyDescriptor.getPropertyType().equals(ArrayList.class)) {
                         //plugin.getLogger().info("DEBUG: Adding a list ");
                         // Loop through the collection resultset 
                         // Note that we have no idea what type this is
-                        List<Type> collectionTypes = getCollectionParameterTypes(method);
+                        List<Type> collectionTypes = Util.getCollectionParameterTypes(method);
                         // collectionTypes should be only 1 long
                         Type setType = collectionTypes.get(0);
                         value = new ArrayList<Object>();
@@ -655,14 +634,14 @@ public class MySQLDatabaseHandler<T> extends AbstractDatabaseHandler<T> {
                         while (collectionResultSet.next()) {
                             //plugin.getLogger().info("DEBUG: adding to the list");
                             //plugin.getLogger().info("DEBUG: collectionResultSet size = " + collectionResultSet.getFetchSize());
-                            ((List<Object>) value).add(deserialize(collectionResultSet.getObject(1),setType.getClass()));
+                            ((List<Object>) value).add(deserialize(collectionResultSet.getObject(1),Class.forName(setType.getTypeName())));
                         }
                     } else if (propertyDescriptor.getPropertyType().equals(Map.class) ||
                             propertyDescriptor.getPropertyType().equals(HashMap.class)) {
                         //plugin.getLogger().info("DEBUG: Adding a map ");
                         // Loop through the collection resultset 
                         // Note that we have no idea what type this is
-                        List<Type> collectionTypes = getCollectionParameterTypes(method);
+                        List<Type> collectionTypes = Util.getCollectionParameterTypes(method);
                         // collectionTypes should be 2 long
                         Type keyType = collectionTypes.get(0);
                         Type valueType = collectionTypes.get(1);
@@ -673,9 +652,9 @@ public class MySQLDatabaseHandler<T> extends AbstractDatabaseHandler<T> {
                             //plugin.getLogger().info("DEBUG: collectionResultSet size = " + collectionResultSet.getFetchSize());
                             // Work through the columns
                             // Key
-                            Object key = (deserialize(collectionResultSet.getObject(1),keyType.getClass()));
+                            Object key = deserialize(collectionResultSet.getObject(1),Class.forName(keyType.getTypeName()));
                             //plugin.getLogger().info("DEBUG: key = " + key);
-                            Object mapValue = (deserialize(collectionResultSet.getObject(2),valueType.getClass()));
+                            Object mapValue = deserialize(collectionResultSet.getObject(2),Class.forName(valueType.getTypeName()));
                             //plugin.getLogger().info("DEBUG: value = " + mapValue);
                             ((Map<Object,Object>) value).put(key,mapValue);
                         }

src/main/java/us/tastybento/bskyblock/util/Util.java

@@ -1,6 +1,12 @@
 package us.tastybento.bskyblock.util;
 
 import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
+import java.lang.reflect.ParameterizedType;
+import java.lang.reflect.Type;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
 
 import org.bukkit.Bukkit;
 import org.bukkit.ChatColor;
@@ -113,4 +119,27 @@ public class Util {
         }
         return location.getWorld().getName() + ":" + location.getBlockX() + ":" + location.getBlockY() + ":" + location.getBlockZ() + ":" + Float.floatToIntBits(location.getYaw()) + ":" + Float.floatToIntBits(location.getPitch());
     }
+    
+    /**
+     * Get a list of parameter types for the collection argument in this method
+     * @param writeMethod
+     * @return
+     */
+    public static List<Type> getCollectionParameterTypes(Method writeMethod) {
+        List<Type> result = new ArrayList<Type>();
+        // Get the return type
+        // This uses a trick to extract what the arguments are of the writeMethod of the field.
+        // In this way, we can deduce what type needs to be written at runtime.
+        Type[] genericParameterTypes = writeMethod.getGenericParameterTypes();
+        // There could be more than one argument, so step through them
+        for (int i = 0; i < genericParameterTypes.length; i++) {
+            // If the argument is a parameter, then do something - this should always be true if the parameter is a collection
+            if( genericParameterTypes[i] instanceof ParameterizedType ) {
+                // Get the actual type arguments of the parameter 
+                Type[] parameters = ((ParameterizedType)genericParameterTypes[i]).getActualTypeArguments();
+                result.addAll(Arrays.asList(parameters));
+            }
+        }
+        return result;
+    }
 }