Merge pull request onlyliuxin#12 from CheungChanDevCoder/master

zhijiaxinyu · web-flow · commit 88198126dc3a · 2017-02-27T13:13:18.000+08:00
第一次作业，By：584709796，史栋栋
diff --git a/group05/1377699408/.gitignore b/group05/1377699408/.gitignore
@@ -0,0 +1,4 @@
+/bin
+.classpath
+.project
+.settings/
diff --git a/group05/1377699408/作业/20170226/src/list/ArrayList.java b/group05/1377699408/作业/20170226/src/list/ArrayList.java
@@ -0,0 +1,54 @@
+package list;
+
+import java.util.Arrays;
+
+public class ArrayList<E> {
+	private transient static int INITIAL_SIZE = 10;
+	private transient int arrayLength;
+	private transient int size;
+	private transient E[] array;
+	public ArrayList(){
+		array = (E[]) new Object[INITIAL_SIZE];
+		arrayLength = INITIAL_SIZE;
+	}
+	public ArrayList(int size){
+		if(size<=0){
+			throw new IllegalArgumentException("参数不可以小于0");
+		}
+		array = (E[])new Object[size];
+		arrayLength = array.length;
+		ensureCapacity(size);
+		this.size = size;
+	}
+	public int size(){
+		return size;
+	}
+	public void add(E e){
+		ensureCapacity(size+1);
+		array[size] = e;
+		size++;
+	}
+	public E get(int index){
+		if(index<0 || index > size){
+			throw new IllegalArgumentException("索引越界");
+		}
+		return array[index];
+		
+	}
+	public E set(int index, E e){
+		if(index<0 || index>size){
+			throw new IllegalArgumentException("索引越界");
+		}
+		E result = array[index];
+		array[index] = e;
+		return result;
+	}
+	private void ensureCapacity(int size){
+		E[] oldArray = array;
+		int oldSize = arrayLength;
+		while(size>arrayLength){
+			arrayLength = arrayLength + (arrayLength >> 1);
+			array = Arrays.copyOf(oldArray, arrayLength);
+		}
+	}
+}
diff --git a/group05/1377699408/作业/20170226/src/test/ArrayListTest.java b/group05/1377699408/作业/20170226/src/test/ArrayListTest.java
@@ -0,0 +1,59 @@
+package test;
+
+import junit.framework.TestCase;
+import list.ArrayList;
+
+public class ArrayListTest extends TestCase {
+
+	protected void setUp() throws Exception {
+		super.setUp();
+	}
+
+	protected void tearDown() throws Exception {
+		super.tearDown();
+	}
+
+	public void testArrayList() {
+		ArrayList<Integer> a = new ArrayList<Integer>();
+		assertEquals(a.size(), 0);
+	}
+
+	public void testArrayListInt() {
+		ArrayList<Integer> a = new ArrayList<Integer>(9);
+		assertEquals(a.size(), 9);
+	}
+
+	public void testSize() {
+		ArrayList<Integer> a = new ArrayList<Integer>(9);
+		assertEquals(a.size(), 9);
+		ArrayList<Integer> a2 = new ArrayList<Integer>(100);
+		assertEquals(a2.size(), 100);
+	}
+
+	public void testAdd() {
+		ArrayList<Integer> a = new ArrayList<Integer>();
+		for (int i = 0; i < 1000; i++) {
+			a.add(5);
+			assertEquals(a.size(), i+1);
+			assertEquals(a.get(i), new Integer(5));
+		}
+	}
+
+	public void testGet() {
+		ArrayList<Integer> a = new ArrayList<Integer>();
+		a.add(6);
+		assertEquals(a.get(0), new Integer(6));
+		
+	}
+
+	public void testSet() {
+		ArrayList<Integer> a = new ArrayList<Integer>();
+		for (int i = 0; i < 100; i++) {
+			a.add(56);
+		}
+		a.set(5, 66);
+		assertEquals(a.get(5), new Integer(66));
+		assertEquals(a.get(7), new Integer(56));
+	}
+
+}
