EnumSet complementOf(EnumSet e): 创建一个其元素类型与指定EnumSet里元素类型相同的EnumSet集合,新EnumSet集合包含原EnumSet集合所不包含的、此类枚举类剩下的枚举值(即新EnumSet集合和原EnumSet集合的集合元素加起来是该枚举类的所有枚举值)。 EnumSet copyOf(Collection c): 使用一个普通集合来创建EnumSet集合。 EnumS...
1Exception in thread "main"java.lang.ClassCastException: Err cannot be cast to java.lang.Comparable2at java.util.TreeMap.compare(Unknown Source)3at java.util.TreeMap.put(Unknown Source)4at java.util.TreeSet.add(Unknown Source)5at TreeSetErrorTest.main(TreeSetErrorTest.java:13) 上面程序试图向...
// Java program to iterate TreeSet collection // in descending order import java.io.*; import java.util.*; public class Main { public static void main(String args[]) { TreeSet < Integer > tree = new TreeSet < Integer > (); tree.add(25); tree.add(20); tree.add(35); tree....
Java Collection框架(七)红黑树与TreeNode源码浅析 2018年拍摄于京都平安神宫内。 今天看树型数据结构。 树 上图是一个简单的树形结构,最顶层为一个根节点,向下延伸出树杈和叶子构成一个具有层次关系的集合,例如前端树形插件Ztree,用过的朋友都很熟悉知道这个结构。 一个节点也是一颗树,这个节点就是root根节点,上...
1.Collection接口:单列集合,用来存储一个一个的对象 2.Set接口:存储无序的,不可重复的数据 ,说白了就是高中讲的"集合" 3.HashSet接口:作为Set接口的主要实现类,线程不安全的,可以存储null值 4.LinkedHashSet:作为HashSet的子类,遍历其内部数据时,可以按照添加的顺序进行遍历。
I am familiar with Java Collection Framework which contains basic interfaces: Collection and Map. I am wondering why the Framework doesn’t contain structures as Tree and Graph which are basic collections. Both can be regarded as sub types of Collection. ...
Collection<V>values() Returns a Collection view of the values contained in this map. Methods inherited from class java.util.AbstractMap equals, hashCode, isEmpty, toString Methods inherited from class java.lang.Object finalize, getClass, notify, notifyAll, wait, wait, wait Methods inherited from...
Collection.addAll(Collection) putAll public void putAll(Tree that) Puts all of the nodes in the specified Tree to this Tree (including the ones that are already present). This operation effectively modifies this Tree so that its value is the union of the two Trees. The behavior of this...
1 import java.util.Iterator; 2 import java.util.TreeSet; 3 public class StudentCode { 4 5 public static void main(String []args){ 6 //定义TreeSet对象,并赋值java存在的对象 7 TreeSet ts1=new TreeSet(); 8 ts1.add("java10"); 9 ts1.add("java01"); 10 ts1.add("java08"); 11...
Java Collection, TreeSet Exercises and solution: Write a Java program to retrieve and remove the first element of a tree set.