@Test public void withConstructor(){ List<String> stringList=new ArrayList<>(Arrays.asList("a","b","c")); List<String> copyList = new ArrayList<>(stringList); copyList.set(0,"e"); log.info("{}",stringList); log.
public class MapStructTest { @Test public void fun1() { List<User> list = new ArrayList<>(); list.add(DataUtil.build(User.class)); list.add(DataUtil.build(User.class)); list.add(DataUtil.build(User.class)); PageBean<User> userPageBean = new PageBean<>(); userPageBean.setPages(10)...
java ArrayList<String> shallowCopiedListUsingConstructor = new ArrayList<>(originalList); 3. 如果需要深拷贝,遍历原始ArrayList,并手动复制每个元素到新ArrayList 深拷贝意味着新列表不仅与原列表有不同的引用,而且其元素也是新的、不共享的。对于包含基本数据类型或不可变对象的ArrayList,浅拷贝通...
使用构造函数 ArrayList有个构造函数,可以传入一个集合: publicArrayList(Collection<? extends E> c){ elementData = c.toArray();if((size = elementData.length) !=0) {// c.toArray might (incorrectly) not return Object[] (see 6260652)if(elementData.getClass() != Object[].class) elementData =...
@Testpublic void withConstructor(){List<String> stringList=new ArrayList<>(Arrays.asList("a","b","c"));List<String> copyList = new ArrayList<>(stringList);copyList.set(0,"e");log.info("{}",stringList);log.info("{}",copyList);List<CustBook> objectList=new ArrayList<>(Arrays.as...
@Test public void withConstructor(){ List<String> stringList=new ArrayList<>(Arrays.asList("a","b","c")); List<String> copyList = new ArrayList<>(stringList); copyList.set(0,"e"); log.info("{}",stringList); log.info("{}",copyList); List<CustBook> objectList=new ArrayList<...
@Testpublic void withConstructor(){List<String> stringList=new ArrayList<>(Arrays.asList("a","b","c"));List<String> copyList = new ArrayList<>(stringList);copyList.set(0,"e");log.info("{}",stringList);log.info("{}",copyList);List<CustBook> objectList=new ArrayList<>(Arrays.as...
public void withConstructor(){ List<String> stringList=new ArrayList<>(Arrays.asList("a","b","c"));List<String> copyList = new ArrayList<>(stringList);copyList.set(0,"e");log.info("{}",stringList);log.info("{}",copyList);List<CustBook> objectList=new ArrayList<>(Arrays.asList...
2. Constructor A simple way to copy aListis by using the constructor that takes a collection as its argument: List<Plant> copy =newArrayList<>(list);Copy Since we’re copying references here, and not cloning the objects, every amends made in one element will affect both lists. ...
importjava.util.ArrayList;importjava.util.List;publicclassCopyWithConstructor{publicstaticvoidmain(String[]args){List<String>originalList=newArrayList<>();originalList.add("A");originalList.add("B");// 使用构造函数复制List<String>copiedList=newArrayList<>(originalList);System.out.println("原始列表:...