Fix interval flags (fixes #2302)

Core/src/main/java/com/github/intellectualsites/plotsquared/plot/flag/IntervalFlag.java

@@ -1,17 +1,20 @@
 package com.github.intellectualsites.plotsquared.plot.flag;
 
-public class IntervalFlag extends Flag<Integer[]> {
+import lombok.EqualsAndHashCode;
+import lombok.Getter;
+import lombok.RequiredArgsConstructor;
+
+public class IntervalFlag extends Flag<IntervalFlag.Interval> {
 
     public IntervalFlag(String name) {
         super(name);
     }
 
     @Override public String valueToString(Object value) {
-        Integer[] value1 = (Integer[]) value;
-        return value1[0] + " " + value1[1];
+        return value.toString();
     }
 
-    @Override public Integer[] parseValue(String value) {
+    @Override public Interval parseValue(String value) {
         int seconds;
         int amount;
         String[] values = value.split(" ");
@@ -32,10 +35,22 @@ public class IntervalFlag extends Flag<Integer[]> {
         } else {
             return null;
         }
-        return new Integer[] {amount, seconds};
+        return new Interval(amount, seconds);
     }
 
     @Override public String getValueDescription() {
         return "Value(s) must be numeric. /plot set flag <flag> <interval> [amount]";
     }
+
+    @EqualsAndHashCode @RequiredArgsConstructor @Getter public static final class Interval {
+
+        private final int val1;
+        private final int val2;
+
+        public String toString() {
+            return String.format("%d %d", this.val1, this.val2);
+        }
+
+    }
+
 }