Commons Collections Apache Commons is a project of the Apache Software Foundation and was once part of the Jakarta project. The purpose of Commons is to provide reusable, open source Java code that solves various practical common problems. Commons consists of three parts: Proper (which are some published projects), Sandbox (which are some projects under […]
Tag: collections
Python data containers – collections and dictionaries
1. Slicing of data container (sequence) 1. The meaning of sequence A type of data container with continuous and ordered content that supports subscript indexing 2. Classification of sequences List, tuple, string 3. Characteristics of sequences In addition to subscript indexing, ordering, repeatability, and support for while loops, the biggest feature is that it supports […]
Collection tools: Collections, Landlord Game
Table of Contents Collections: is a tool class used to operate collections Landlord game Collections: is a tool class used to operate collections Common static methods provided by Collections Collections can only support sorting List collections package com.xinbao.d6_parameter; public class Student implements Comparable<Student>{ private String name; private double score; private int age; @Override public int […]
Python collections (lists, tuples, dictionaries)
Python collections (lists, tuples, dictionaries) Table of contents One: List 1.1 List overview 1.2 Add, delete, modify and check the list 1.2.1 Find elements in a list 1.2.2 Adding elements to the list 1.2.3 Modify elements in the list 1.2.4 Delete elements in the list 1.3 List traversal loop 1.3.1 for loop traverses the list […]
Beautiful JUC Part.8Concurrent collections such as ConcurrentHashMap
[Beautiful JUC Part.8] ConcurrentHashMap and other concurrent collections Overview of concurrent containers, history of collection classes, ConcurrentHashMap (key points, common interview tests) CopyOnWriteArrayList, concurrent queue Queue (blocking queue, non-blocking queue) 1. Overview of concurrent containers ConcurrentHashMap: Thread-safe HashMap CopyOnWriteArrayList: Thread-safe List BlockingQueue: This is an interface that represents a blocking queue, which is very suitable […]
JavaScript implements collections and dictionaries
Javascript implements collections and dictionaries 1. Collection structure 1.1. Introduction A common implementation method for collections is hash table, which is encapsulated using the JavaScript Object class. A set is usually composed of a group of unordered and unrepeatable elements. The elements of a set often referred to in mathematics can be repeated, but the […]
Java three time period collections are merged into one time period collection
If you have three time period collections and want to merge them into one time period collection, you can follow these steps: Combine three time period sets into one large time period set. Sort the merged time period set according to the start time to ensure that they are arranged in chronological order. Check the […]
Java collection tool class Collections
1. Collections tool class With the foundation of variable parameters in the previous article, it will be easier for us to learn about Collections, a tool class, because variable parameters will be used in the methods of this tool class. 1. Overview of Collections tool class java.lang.Collections: It is a collection tool class. Function: Collections […]
Variable parameters and Collections tool class
1. Variable parameters import java.util.Arrays; public class ParameterTest { public static void main(String[] args) { //Features //1.Do not transmit data test(); //2.A data test(1); //3.Multiple data test(1,2,3); //4. Pass in the array test (new int[]{1,2,3,4,5,6}); } //Note 1: There can only be one variable parameter in a formal parameter list //Note 2: Variable parameters must […]
Several traversal methods of collections + intermediate processing
Note: The size of the list created by the Arrays.asList() method is fixed, so we cannot use the add or remove method Change the size of the list. Otherwise an UnsupportedOperationException will be thrown. To be able to add and remove elements, you need to use an ArrayList (or other mutable list type). 1. Use […]