Scanner scSystemin//KeySystemoutprintln"请输入要查询的学生id:"String id=scnextSystemoutprintlnididSystemoutidname//ValueSystem.out.println("请输入要查询的学生姓名:");String name=sc.next();if(students.containsValue(newStudent(null
在Map中,用containsKey()方法,判断是否包含某个Key值;用containsValue()方法,判断是否包含某个Value值。 以下是MapTest类的部分示例代码: packagecom.test.collection; publicclassMapTest {publicMap<String, Student>students;publicScanner console;publicMapTest() {this.students =newHashMap<String, Student>();th...
可以看到,通过containsKey(Object key)方法比较的结果返回true,是我们想要的结果。通过containsValue(Object value)方法比较的结果返回是false,但是我们确实是有一个名字叫小明的学生啊。为什么呢? 查看containsKey(Object key)和containsValue(Object value)的API说明: containsKey(Object key):Returns true if this map c...
HashSet将元素存放在HashMap中(HashMap的key) contains()方法调用HashMap的containsKey()方法 containsKey()方法调用getEntry()方法。在该方法中,首先根据key计算hash值,然后从HashMap中取出该hash值对应的链表(链表的元素个数将很少),再通过变量该链表判断是否存在给定值。这种实现方式效率将比ArrayList的实现方法效率高...
In this tutorial we will go overHashmapand two of it’s operationboolean containsKey(Object key)andboolean containsValue(Object value). Let’s look at below Java code package com.crunchify.tutorials; import java.util.HashMap; import java.util.Map; ...
Code Issues Pull requests javascript event modal-windows classlist contains keydown Updated Sep 27, 2021 JavaScript Load more… Improve this page Add a description, image, and links to the contains topic page so that developers can more easily learn about it. Curate this topic Add this...
[Android.Runtime.Register("contains", "(Ljava/lang/Object;)Z", "GetContains_Ljava_lang_Object_Handler:Java.Util.ICollectionInvoker, Mono.Android, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null")] public bool Contains(Java.Lang.Object? o); Parameters o Object element whose presence in...
Set the key property: The field/property in the event based on which you want to filter. StringContainsAdvancedFilterwithValues(List<String> values) Set the values property: The set of filter values. Methods inherited fromAdvancedFilter Methods inherited from java.lang.Object ...
key Int32 Potential key in the mapping Returns Boolean true if the key is defined in the mapping Attributes RegisterAttribute Remarks Returns true if the key exists in the array. This is equivalent to#indexOfKey(int)>= 0. Java documentation forandroid.util.SparseArray.contains(int). ...
[Java数据结构]Map的contiansKey和List的contains比较 2019-12-25 10:00 − Map的containskey方法使用哈希算法查找key是否存在,运算时间是常数; List的contains方法是将元素在列表中遍历,运算时间和列表长度有关。 我使用两种不同SQL语句获取两种不同类型的结果集进行比较,发现两者差别很明显。 名称 类型 比较方法 ...