@@ -26,6 +26,7 @@ of this software and associated documentation files (the "Software"), to deal
 
 import org.json.stream.JSONStreamReader.ParseState;
 import org.json.util.JSONPointerUtils;
+import org.json.util.SizedIterable;
 
 /**
  * Filtering for structures during a parse. Provided by the {@link BuilderLimits}
@@ -46,7 +47,7 @@ public interface LimitFilter {
      * @return {@code true} to allow the value to be created, otherwise
      * {@code false} to skip the value
      */
-    boolean acceptIndex(int index, ParseState state, Iterable<StructureBuilder> stack);
+    boolean acceptIndex(int index, ParseState state, SizedIterable<StructureBuilder> stack);
 
     /**
      * Determine whether to accept or reject a value within an object.
@@ -58,6 +59,6 @@ public interface LimitFilter {
      * @return {@code true} to allow the value to be created, otherwise
      * {@code false} to skip the value
      */
-    boolean acceptField(String fieldName, ParseState state, Iterable<StructureBuilder> stack);
+    boolean acceptField(String fieldName, ParseState state, SizedIterable<StructureBuilder> stack);
 
 }
@@ -35,7 +35,7 @@ of this software and associated documentation files (the "Software"), to deal
  * @author JSON.org
  * @version 2016-6-30
  */
-public final class ALStack<E> implements Iterable<E> {
+public final class ALStack<E> implements SizedIterable<E> {
     private final ArrayList<E> elements;
 
     /**
@@ -97,6 +97,7 @@ public E peek() throws EmptyStackException {
      *
      * @return {@code true} if the stack is empty, otherwise {@code false}
      */
+    @Override
     public boolean isEmpty() {
         return elements.isEmpty();
     }
@@ -106,6 +107,7 @@ public boolean isEmpty() {
      *
      * @return the number of elements on the stack
      */
+    @Override
     public int size() {
         return elements.size();
     }
 
@@ -0,0 +1,16 @@
+package org.json.util;
+
+/**
+ * Adds size information to an {@code Iterable}. For when a {@code Collection}
+ * has too big a contract.
+ *
+ * @author JSON.org
+ * @version 2016-08-07
+ */
+public interface SizedIterable<T> extends Iterable<T> {
+
+    int size();
+
+    boolean isEmpty();
+
+}
Original file line number	Diff line number	Diff line change
`@@ -35,7 +35,7 @@ of this software and associated documentation files (the "Software"), to deal`
`35`	`35`	`* @author JSON.org`
`36`	`36`	`* @version 2016-6-30`
`37`	`37`	`*/`
`38`		`-public final class ALStack<E> implements Iterable<E> {`
	`38`	`+public final class ALStack<E> implements SizedIterable<E> {`
`39`	`39`	`private final ArrayList<E> elements;`
`40`	`40`
`41`	`41`	`/**`
`@@ -97,6 +97,7 @@ public E peek() throws EmptyStackException {`
`97`	`97`	`*`
`98`	`98`	`* @return {@code true} if the stack is empty, otherwise {@code false}`
`99`	`99`	`*/`
	`100`	`+ @Override`
`100`	`101`	`public boolean isEmpty() {`
`101`	`102`	`return elements.isEmpty();`
`102`	`103`	`}`
`@@ -106,6 +107,7 @@ public boolean isEmpty() {`
`106`	`107`	`*`
`107`	`108`	`* @return the number of elements on the stack`
`108`	`109`	`*/`
	`110`	`+ @Override`
`109`	`111`	`public int size() {`
`110`	`112`	`return elements.size();`
`111`	`113`	`}`