Programmer Group

enumeration Format of enumeration Permission modifier enum enumeration name{               Example 1, example 2, example 3, example 4; } package com.meiju; public enum Level2 { LOW(1),MEDIUM(50),HIGH(100); private int levelValue; private Level2(int levelValue){ this.levelValue=le ...

IO stream First, we should understand external memory, memory and cache io is divided into input and output: Personal understanding: Output stream: output the file from the idea Input stream: read the file to the idea Input and output can be divided into: Byte stream: the smallest data unit in a data stream is bytes Output: OutputSt ...

Development tool preparation Development tool: idea2017 up Dependency management: Maven 3 or above JDK: above 1.8 Creating a Spring project using Maven Select MavenCheck Create from archetypeSelect Maven archetype QuickStart Created successfully Creating a Spring project using Java Enterprise Default Version generally selects Java ...

preface Now more and more projects begin to use workflow to meet their daily work. Today, let's take a look at the workflow of Activiti. Let's start with BPMN painting Environment installation BPMN documents about processes are mainly integrated through eclipse development tools. The idea is mainly painted by actiBPM, but actiBPM is no long ...

io usage scenarios When we want to store some data in the disk so that the data can be found when the program closes and runs again, we need to write the data out of the program with io stream, write it to the local file, or save it to the database, etc. iO details Check the java API documentation -- java.base -- java.io. It is found ...

Mybatis generator source code learning and modification Required jar package: generator-mybatis-generator-1.3.2.jar Background: The company's database is divided into sub databases. During query, the customerId must be modified, otherwise the query efficiency will become low. The database table 60 +, almost every table of the new projec ...

         There are many methods of virtual machine allocation strategy in cloud computing. Now it is placed in the cloudsim project package with scheduling methods such as Random allocation, first fit, best fit and RoundRobin. The optimization process of virtual machine scheduling problem can also refer t ...

This article is mainly about maven from environment configuration to being used in IDEA. Basically, the problems encountered are also mentioned. If not mentioned, welcome to communicate In Java Web development, we need to manually import a large number of jar packages, and maven helps us import and configure this jar package, 1.maven pro ...

catalogue Article catalog preface 1, Create Maven project 2, POM configuration 1. Configure JDK version and encoding method 2. Set resource file path   3. Add dependency 4. All of POM documents 3, Initialization data   4, Configure mybatis-config.xml 5, Configure config.properties 6, Configure log4j.properties 7, Create t ...

Java classes and objects The main unit of object-oriented programming language is class, and class is a user-defined type. The variables created by class are called objects. Classes and objects are the most common words in object-oriented programming. Three foundations of object orientation: Encapsulation, packaging data types and method ...