*/publicclassArrayListTest{publicstaticvoidmain(String[]args){ArrayList<String>list=newArrayList<String>();list.add("Java");list.add("Python");list.add("C++");// 使用for循环遍历元素for(inti=0;i<list.size();i++){Stringelement=list.get(i);System.out.println(element);}// 使用foreach语句遍历元素
AI代码解释 importjava.util.ArrayList;importjava.util.Arrays;publicclassArrayListTest{classHuman{}classMaleextendsHuman{}publicstaticvoidmain(String[]args){ArrayList<Integer>list1=newArrayList<Integer>();list1.add(1);// Appends the specified element to the end of this listlist1.add(2);list1.add(...
public void remove(ArrayList<Integer> list) { Integer in = 1; for (int i = 0; i < list.size(); i++) { Integer s = list.get(i); if ( s.equals(in) ) { list.remove(s); } } } 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 看上去我们的代码很完美,在理论上肯定会达到预...
checkForComodification();returnArrayList.this.elementData(offset +index); } 第二,for循环,以Integer元素为例 Integer value =null;for(Integer integ:list) { value=integ; } 第三,通过迭代器(Iterator)去遍历,以Integer元素为例 Integer value =null; Iterator iter=list.iterator();while(iter.hasNext()) ...
Java ArrayList小记 1.基本用法 ArrayList是一个泛型容器,新建ArrayList需要实例化泛型参数,比如: ArrayList<String> StrList =newArrayList<>(); ArrayList<Integer> intList =newArrayList<>(); ArrayList的主要方法有: //添加元素到末尾publicbooleanadd(E e)//判断是否为空publicbooleanisEmpty()//获取大小public...
* Attempts to allocate larger arrays may result in * OutOfMemoryError: Requested array size exceeds VM limit */ private static final int MAX_ARRAY_SIZE = Integer.MAX_VALUE - 8; 1. 2. 3. 4. 5. 6. 7. 上面这个图其实就是扩容的源码,我们看到其实ArrayList在扩容的时候其实就是看最小容量(...
List<Integer>list=newArrayList<>();list.add(4);list.add(2);list.add(3);list.add(5);for(inti:list) { System.out.println(i); } System.out.println(list); 运行结果: 4235[4,2,3,5] 可以发现ArrayList是按插入顺序存储的,这也不奇怪,每次插入是在elementData[size++]处插入。
voidforEach(Consumer<? superE> action) Performs the given action for each element of theIterableuntil all elements have been processed or the action throws an exception. Eget(int index) Returns the element at the specified position in this list. ...
HashMap<String,Integer>details=newHashMap<>();details.put("keanu",23);details.put("max",24);details.put("john",53);names.addAll(details.keySet());//Adding multiple elements in ArrayList 3. Initialize ArrayList from Java 8 Stream
see 6260652 是JDK bug库的编号,有点像商品sku,bug地址:https://bugs.java.com/bugdatabase/view_bug.do?bug_id=6260652 那这是个什么bug呢,我们来测试下面这段代码; @Test public void t(){ List<Integer> list1 = Arrays.asList(1, 2, 3); ...