packagecollection;importjava.util.Comparator;publicclassStudentComparatorimplementsComparator<Student> {@Overridepublicintcompare(Student o1, Student o2){// 排序规则描述如下// 按照姓名的长度排序,长度短的排在前面,长度长的排在后面//
o1.getName().compareTo(o2.getName()) : orderByNameLength;int orderByAge = orderByName == 0 ? o1.getAge() - o2.getAge() : orderByName;return orderByAge;}} 然后修改下验证代码中声明studentTreeSet的代码即可: TreeSet<Student> studentTreeSet = new TreeSet<>(new StudentComparator())...
super E> comparator() { return m.comparator(); } //返回第一个元素 public E first() { return m.firstKey(); } //返回最后一个元素 public E last() { return m.lastKey(); } // NavigableSet API methods /** * 返回小于e的最大的元素,没有就返回null */ public E lower(E e) { retu...
* add(int index, E element)在此列表中指定的位置插入指定的元素。 * addFirst(E e) 将指定元素插入此列表的开头。(LinkedList特有的) * addLast(E e)将指定元素添加到此列表的结尾。(LinkedList特有的) * getFirst() 返回此列表的第一个元素。 * getLast() 返回此列表的最后一个元素。 * removeFirst()...
Comparator.comparingInt(Providers::getPriority), CustomAnnotationLiteral.INSTANCE); providers.addAll(getServiceHolders(injectionManager, contract)); LinkedHashSet<ServiceHolder<T>> providersSet = new LinkedHashSet<>(); for (ServiceHolder<T> provider : providers) { if (!providersSet.contains(provider)...
private static Ordering<String> createExplicitComparator(String[] elements) { // Collapse equal elements, which Ordering.explicit() doesn't support, while // maintaining the ordering by first occurrence. Set<String> elementsPlus = Sets.newLinkedHashSet(); elementsPlus.add(BEFORE_FIRST); elementsPl...
type List interface { Get(index int) (interface{}, bool) Remove(index int) Add(values ...interface{}) Contains(values ...interface{}) bool Sort(comparator utils.Comparator) Swap(index1, index2 int) Insert(index int, values ...interface{}) Set(index int, value interface{}) containers....
Remove(1) // 2->b m.Clear() // empty m.Empty() // true m.Size() // 0 } TreeMap A map based on red-black tree. Keys are ordered ordered with respect to the comparator. Implements Map, IteratorWithKey, EnumerableWithKey, JSONSerializer and JSONDeserializer interfaces. package main ...
System.out.println(b);//true//List集合一直返回true,Set出现重复返回falseSystem.out.println(b1);//trueSystem.out.println(c);//[abc, Student [name=张三, age=12]]System.out.println(c.contains("abc"));//true//是否包含c.remove("abc"); ...