diff --git a/src/BodyLinkedList.java b/src/BodyLinkedList.java index 454dbf7..e568efe 100644 --- a/src/BodyLinkedList.java +++ b/src/BodyLinkedList.java @@ -6,8 +6,8 @@ import java.util.Iterator; */ public class BodyLinkedList implements Iterable { private int size = 0; - private BodyLinkedListItem first; - private BodyLinkedListItem last; + private Item first; + private Item last; /** * Initializes 'this' as an empty list. @@ -35,11 +35,11 @@ public class BodyLinkedList implements Iterable { */ public void addFirst(Body body) { if (first == null) { - first = new BodyLinkedListItem(body); + first = new Item(body); last = first; } else { - first.setPrev(new BodyLinkedListItem(body)); - first = first.prev(); + first.setPrev(new Item(body)); + first = first.prev; } size++; } @@ -49,11 +49,11 @@ public class BodyLinkedList implements Iterable { */ public void addLast(Body body) { if (last == null) { - last = new BodyLinkedListItem(body); + last = new Item(body); first = last; } else { - last.setNext(new BodyLinkedListItem(body)); - last = last.next(); + last.setNext(new Item(body)); + last = last.next; } size++; } @@ -63,7 +63,7 @@ public class BodyLinkedList implements Iterable { * Returns 'null' if the list is empty. */ public Body getLast() { - return (last != null) ? last.body() : null; + return (last != null) ? last.body : null; } /** @@ -71,7 +71,7 @@ public class BodyLinkedList implements Iterable { * Returns 'null' if the list is empty. */ public Body getFirst() { - return (first != null) ? first.body() : null; + return (first != null) ? first.body : null; } /** @@ -82,8 +82,8 @@ public class BodyLinkedList implements Iterable { if (first == null) { return null; } - Body b = first.body(); - first = first.next(); + Body b = first.body; + first = first.next; if (first != null) first.setPrev(null); size--; return b; @@ -97,8 +97,8 @@ public class BodyLinkedList implements Iterable { if (last == null) { return null; } - Body b = last.body(); - last = last.prev(); + Body b = last.body; + last = last.prev; if (last != null) last.setNext(null); size--; return b; @@ -117,28 +117,28 @@ public class BodyLinkedList implements Iterable { return; } - BodyLinkedListItem item = first; + Item item = first; for (int j = 0; j < i; j++) { - item = item.next(); + item = item.next; } - item.prev().setNext(new BodyLinkedListItem(body)); - item.setPrev(item.prev().next()); + item.prev.setNext(new Item(body)); + item.setPrev(item.prev.next); size++; } - private Body removeItem(BodyLinkedListItem item) { + private Body removeItem(Item item) { if (item == first) { - first = item.next(); + first = item.next; if (first != null) first.setPrev(null); } else if (item == last) { - last = item.prev(); + last = item.prev; if (last != null) last.setNext(null); } else { - item.next().setPrev(item.prev()); + item.next.setPrev(item.prev); } size--; - return item.body(); + return item.body; } /** @@ -146,19 +146,19 @@ public class BodyLinkedList implements Iterable { * Precondition: i >= 0 && i < size(). */ public Body get(int i) { - BodyLinkedListItem item; + Item item; if (i < size / 2) { item = first; for (int j = 0; j < i; j++) { - item = item.next(); + item = item.next; } } else { item = last; for (int j = size - 1; j > i; j--) { - item = item.prev(); + item = item.prev; } } - return item.body(); + return item.body; } /** @@ -170,12 +170,12 @@ public class BodyLinkedList implements Iterable { return -1; } - BodyLinkedListItem item = first; + Item item = first; for (int i = 0; i < size; i++) { - if (item.body() == body) { + if (item.body == body) { return i; } - item = item.next(); + item = item.next; } return -1; @@ -187,8 +187,8 @@ public class BodyLinkedList implements Iterable { */ public BodyLinkedList removeCollidingWith(Body body) { BodyLinkedList removed = new BodyLinkedList(); - for (BodyLinkedListItem item = first; item != null; item = item.next()) { - if (body != item.body() && body.collidesWith(item.body())) { + for (Item item = first; item != null; item = item.next) { + if (body != item.body && body.collidesWith(item.body)) { removed.addLast(this.removeItem(item)); } } @@ -205,57 +205,45 @@ public class BodyLinkedList implements Iterable { @Override public Iterator iterator() { return new Iterator<>() { - BodyLinkedListItem ptr = first; + Item ptr = first; boolean yieldedFirst = false; @Override public boolean hasNext() { - return ptr != null && (!yieldedFirst || ptr.next() != null); + return ptr != null && (!yieldedFirst || ptr.next != null); } @Override public Body next() { if (!yieldedFirst) { yieldedFirst = true; - return ptr.body(); + return ptr.body; } - ptr = ptr.next(); - return ptr.body(); + ptr = ptr.next; + return ptr.body; } }; } -} -class BodyLinkedListItem { - private final Body body; - private BodyLinkedListItem prev; - private BodyLinkedListItem next; + private class Item { + private final Body body; + private Item prev; + private Item next; - public BodyLinkedListItem(Body body) { - this.body = body; - this.prev = null; - this.next = null; - } + public Item(Body body) { + this.body = body; + this.prev = null; + this.next = null; + } - public Body body() { - return body; - } + public void setPrev(Item prev) { + this.prev = prev; + if (prev != null) prev.next = this; + } - public BodyLinkedListItem prev() { - return prev; - } - - public void setPrev(BodyLinkedListItem prev) { - this.prev = prev; - if (prev != null) prev.next = this; - } - - public BodyLinkedListItem next() { - return next; - } - - public void setNext(BodyLinkedListItem next) { - this.next = next; - if (next != null) next.prev = this; + public void setNext(Item next) { + this.next = next; + if (next != null) next.prev = this; + } } }