Use newer Java features in places where it makes sense and more (#1009)

src/main/java/carpet/script/value/AbstractListValue.java

@@ -8,7 +8,7 @@ import java.util.List;
 
 public abstract class AbstractListValue extends Value implements Iterable<Value>
 {
-    public abstract Iterator<Value> iterator();
+    @Override public abstract Iterator<Value> iterator();
     public List<Value> unpack() { return Lists.newArrayList(iterator()); }
     public void fatality() { }
     public void append(Value v)

src/main/java/carpet/script/value/BooleanValue.java

@@ -12,7 +12,7 @@ public class BooleanValue extends NumericValue
 
     boolean boolValue;
     private BooleanValue(boolean boolval) {
-        super(boolval);
+        super(boolval ? 1L : 0L);
         boolValue = boolval;
     }
 

src/main/java/carpet/script/value/EntityValue.java

@@ -412,14 +412,14 @@ public class EntityValue extends Value
             throw new InternalExpressionException("Cannot fetch '"+what+"' with these arguments");
         }
     }
-    private static final Map<String, EquipmentSlot> inventorySlots = new HashMap<String, EquipmentSlot>(){{
-        put("mainhand", EquipmentSlot.MAINHAND);
-        put("offhand", EquipmentSlot.OFFHAND);
-        put("head", EquipmentSlot.HEAD);
-        put("chest", EquipmentSlot.CHEST);
-        put("legs", EquipmentSlot.LEGS);
-        put("feet", EquipmentSlot.FEET);
-    }};
+    private static final Map<String, EquipmentSlot> inventorySlots = Map.of(
+        "mainhand", EquipmentSlot.MAINHAND,
+        "offhand", EquipmentSlot.OFFHAND,
+        "head", EquipmentSlot.HEAD,
+        "chest", EquipmentSlot.CHEST,
+        "legs", EquipmentSlot.LEGS,
+        "feet", EquipmentSlot.FEET
+    );
 
     private static final Map<String, BiFunction<Entity, Value, Value>> featureAccessors = new HashMap<String, BiFunction<Entity, Value, Value>>() {{
         //put("test", (e, a) -> a == null ? Value.NULL : new StringValue(a.getString()));

src/main/java/carpet/script/value/LazyListValue.java

@@ -109,9 +109,9 @@ public abstract class LazyListValue extends AbstractListValue implements Iterato
     {
         return hasNext();
     }
-    public abstract boolean hasNext();
+    @Override public abstract boolean hasNext();
 
-    public abstract Value next();
+    @Override public abstract Value next();
 
     @Override
     public void fatality() {reset();}

src/main/java/carpet/script/value/ListValue.java

@@ -149,6 +149,8 @@ public class ListValue extends AbstractListValue implements ContainerValueInterf
     {
         items.add(v);
     }
+
+    @Override
     public Value subtract(Value other)
     {
         ListValue output = new ListValue();
@@ -182,6 +184,7 @@ public class ListValue extends AbstractListValue implements ContainerValueInterf
     }
 
 
+    @Override
     public Value multiply(Value other)
     {
         ListValue output = new ListValue();
@@ -209,6 +212,8 @@ public class ListValue extends AbstractListValue implements ContainerValueInterf
         }
         return output;
     }
+
+    @Override
     public Value divide(Value other)
     {
         ListValue output = new ListValue();
@@ -272,8 +277,10 @@ public class ListValue extends AbstractListValue implements ContainerValueInterf
         return items;
     }
 
+    @Override
     public Iterator<Value> iterator() { return new ArrayList<>(items).iterator(); } // should be thread safe
 
+    @Override
     public List<Value> unpack()
     {
         return new ArrayList<>(items);

src/main/java/carpet/script/value/NBTSerializableValue.java

@@ -633,26 +633,12 @@ public class NBTSerializableValue extends Value implements ContainerValueInterfa
         return false;
     }
 
-    public static class InventoryLocator
+    public static record InventoryLocator(Object owner, BlockPos position, Inventory inventory, int offset, boolean isEnder)
     {
-        public Object owner;
-        public BlockPos position;
-        public Inventory inventory;
-        public int offset;
-        public boolean isEnder;
         InventoryLocator(Object owner, BlockPos pos, Inventory i, int o)
         {
             this(owner, pos, i, o, false);
         }
-
-        InventoryLocator(Object owner, BlockPos pos, Inventory i, int o, boolean isEnder)
-        {
-            this.owner = owner;
-            position = pos;
-            inventory = i;
-            offset = o;
-            this.isEnder = isEnder;
-        }
     }
 
     private static Map<String, NbtPathArgumentType.NbtPath> pathCache = new HashMap<>();

src/main/java/carpet/script/value/NullValue.java

@@ -33,7 +33,7 @@ public class NullValue extends NumericValue // TODO check nonsingleton code
     {
         return new NullValue();
     }
-    private NullValue() {super(false);}
+    private NullValue() {super(0);}
 
     @Override
     public boolean equals(final Object o)

src/main/java/carpet/script/value/NumericValue.java

@@ -120,6 +120,8 @@ public class NumericValue extends Value
         }
         return super.add(v);
     }
+
+    @Override
     public Value subtract(Value v) {  // TODO test if definintn add(NumericVlaue) woud solve the casting
         if (v instanceof NumericValue nv)
         {
@@ -131,6 +133,8 @@ public class NumericValue extends Value
         }
         return super.subtract(v);
     }
+
+    @Override
     public Value multiply(Value v)
     {
         if (v instanceof NumericValue nv)
@@ -147,6 +151,8 @@ public class NumericValue extends Value
         }
         return new StringValue(StringUtils.repeat(v.getString(), (int) getLong()));
     }
+
+    @Override
     public Value divide(Value v)
     {
         //if (1+2==3) throw new ArithmeticException("Booyah");
@@ -223,17 +229,6 @@ public class NumericValue extends Value
         this.value = (double)value;
     }
 
-    /**
-     * Creates a legacy {@link NumericValue} for a {@code boolean}.
-     * @param boolval The boolean to set 1 or 0 for this {@link NumericValue}
-     * @deprecated Use {@link BooleanValue#of(boolean)} instead
-     */
-    @Deprecated
-    public NumericValue(boolean boolval)
-    {
-        this(boolval?1L:0L);
-    }
-
     @Override
     public int length()
     {