toughened up lookAhead

src/main/java/net/markenwerk/commons/iterators/LookAhead.java

@@ -21,6 +21,8 @@
  */
 package net.markenwerk.commons.iterators;
 
+import java.util.NoSuchElementException;
+
 /**
  * A {@link LookAhead} is a simple container that holds the
  * {@link LookAhead#get() current} and the {@link LookAhead#getNext() next}
@@ -30,7 +32,7 @@
  * @since 1.1.6
  *
  * @param <Payload>
- *            The payload type.
+ *           The payload type.
  */
 public interface LookAhead<Payload> {
 
@@ -47,9 +49,12 @@ public interface LookAhead<Payload> {
 	 * {@literal LookAhead#hashCode() next} payload object.
 	 * 
 	 * @return The next payload object. May be {@literal null}.
+	 * 
+	 * @throws NoSuchElementException
+	 *            If this {@link LookAhead} has no {@link LookAhead#getNext()
+	 *            next} payload object.
 	 */
-
-	public Payload getNext();
+	public Payload getNext() throws NoSuchElementException;
 
 	/**
 	 * Returns whether this {@link LookAhead} has a next payload object.

src/main/java/net/markenwerk/commons/iterators/LookAheadIterator.java

@@ -32,7 +32,7 @@
  * the current and the next payload value of the given {@link Iterator}.
  * 
  * @param <Payload>
- *            The payload type.
+ *           The payload type.
  * @author Torsten Krause (tk at markenwerk dot net)
  * @since 1.1.6
  */
@@ -66,8 +66,12 @@ public Payload get() {
 		}
 
 		@Override
-		public Payload getNext() {
-			return next;
+		public Payload getNext() throws NoSuchElementException {
+			if (!nextExists) {
+				throw new NoSuchElementException("LookAhead has no further element");
+			} else {
+				return next;
+			}
 		}
 
 		@Override
@@ -82,7 +86,7 @@ public boolean isLast() {
 
 		@Override
 		public String toString() {
-			return "Ahead [current=" + current + ", next=" + next + ", hasNext=" + nextExists + "]";
+			return "LookAhead [current=" + current + ", next=" + next + ", hasNext=" + nextExists + "]";
 		}
 
 	}
@@ -100,11 +104,11 @@ public String toString() {
 	 * and the given {@link Predicate}.
 	 * 
 	 * @param iterator
-	 *            The {@link Iterator}, around which the new
-	 *            {@link LookAheadIterator} will be wrapped.
+	 *           The {@link Iterator}, around which the new
+	 *           {@link LookAheadIterator} will be wrapped.
 	 * 
 	 * @throws IllegalArgumentException
-	 *             If the given {@link Iterator} is {@literal null}.
+	 *            If the given {@link Iterator} is {@literal null}.
 	 */
 	public LookAheadIterator(Iterator<? extends Payload> iterator) throws IllegalArgumentException {
 		if (null == iterator) {