Merge pull request #12 from Hipple/master

Master
gqipan · Feb 27, 2017 · 91eeb6e · 91eeb6e
2 parents f8a1eb7 + d5a0650
commit 91eeb6e
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Showing 4 changed files with 77 additions and 3 deletions.
diff --git a/group18/1159828430/20170219/.classpath b/group18/1159828430/20170219/.classpath
@@ -2,6 +2,5 @@
 <classpath>
 	<classpathentry kind="src" path="src"/>
 	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER"/>
-	<classpathentry kind="con" path="org.eclipse.jdt.junit.JUNIT_CONTAINER/4"/>
 	<classpathentry kind="output" path="bin"/>
 </classpath>
diff --git a/group18/1159828430/20170219/src/com/coding/basic/ArrayList.java b/group18/1159828430/20170219/src/com/coding/basic/ArrayList.java
@@ -99,8 +99,9 @@ public boolean isEmpty(){
 		return size == 0;
 	}
 
+	//迭代器
 	public Iterator iterator(){
-		return null;
+		return new ArrayListIterator(this);
 	}
 
 	//动态增加ArrayList大小
@@ -128,6 +129,35 @@ private void fastRemove(int index) {
 		}
 		elementData[--size] = null; 
 	}
+
+	private class ArrayListIterator implements Iterator{
+		private ArrayList list = null;
+		private int cursor = 0;
+		private int lastRet = -1;
+
+		public ArrayListIterator(ArrayList list){
+			this.list = list;
+		}
+		@Override
+		public boolean hasNext() {
+			return cursor != list.size;
+		}
+
+		@Override
+		public Object next() {
+			lastRet = cursor;  
+            Object o = list.get(lastRet);  
+            cursor ++;  
+            return o;  
+		}
+		@Override
+		public void remove() {
+			list.remove(lastRet);  
+			cursor = lastRet;  
+            lastRet = -1; 
+		}
+
+	}
 
 }
 class testArrayList{
@@ -138,8 +168,16 @@ public static void main(String[] args) {
         }
         arrayList.add(5,15);
         arrayList.remove(11);
+        Iterator it = arrayList.iterator();  
+        while(it.hasNext()) {  
+            Integer o = (Integer)it.next();  
+            if(o == 8){  
+                it.remove();  
+            }  
+        }  
         for (int i = 0; i < arrayList.size(); i++) {
             System.out.println("value is "+arrayList.get(i));
         }
+
     }
 }
diff --git a/group18/1159828430/20170219/src/com/coding/basic/Iterator.java b/group18/1159828430/20170219/src/com/coding/basic/Iterator.java
@@ -7,5 +7,6 @@
 public interface Iterator {
 	public boolean hasNext();
 	public Object next();
+	public void remove();
 
 }
diff --git a/group18/1159828430/20170219/src/com/coding/basic/LinkedList.java b/group18/1159828430/20170219/src/com/coding/basic/LinkedList.java
@@ -1,5 +1,6 @@
 package com.coding.basic;
 
+import java.util.ConcurrentModificationException;
 import java.util.NoSuchElementException;
 
 /**
@@ -88,7 +89,7 @@ public Object getFirst() {
     }
 
     public Iterator iterator(){
-        return null;
+        return new LinkedListIterator();
     }
 
     //头部增加节点
@@ -225,6 +226,41 @@ private boolean isPositionIndex(int index) {
         return index >= 0 && index <= size;
     }
 
+    //迭代器
+    private class LinkedListIterator implements Iterator{
+    	private Node lastReturned = null;
+        private Node next;
+        private int nextIndex;
+
+        public boolean hasNext() {
+            return nextIndex < size;
+        }
+
+        public Object next() {
+            if (!hasNext())
+                throw new NoSuchElementException();
+
+            lastReturned = next;
+            next = next.next;
+            nextIndex++;
+            return lastReturned.data;
+        }
+
+        public void remove() {
+            if (lastReturned == null)
+                throw new IllegalStateException();
+
+            Node lastNext = lastReturned.next;
+            unlink(lastReturned);
+            if (next == lastReturned)
+                next = lastNext;
+            else
+                nextIndex--;
+            lastReturned = null;
+        }
+    }
+
+    //节点对象
     private static class Node{
         Object data;
         Node next;