Training notes 7.6

7.6

1. Motto

You tell my story, I leave my words, you decide how much I am worth, and I choose where I go.

2. Setting of compiled memory and running memory of java program

2.1 Compile memory settings:

file--->settings--->buildxxxx--->compiler--->内存的设置

2.2 Stack memory and heap memory settings during Java program running

1. The default stack memory is 1M

   -Xss 设置栈内存的容量

2. The default value of the heap memory startup is generally 1/64 of the physical memory, and the maximum size that can be expanded is 1/4 of the physical memory.

3. application---->edit configuration--->VM Options---> -Xss1M  -Xms100M  -Xmx200M
   

4. The jar package operation can also set the memory:

java -jar -Xss1M -Xms100M -Xmx200M xxx.jar

java -cp -Xss1M -Xms100M -Xmx200M xxx.jar 全限定类名

3. Use of Maven automated build tools

3.1 Help us introduce third-party JAR package dependencies into the project, and at the same time solve the transitive dependencies of third-party jar packages

pom.xml file

GAVS坐标 Scope: compile test provided

remote warehouse

local warehouse

3.2 Maven can also help us to automatically compile, test, package, install and deploy projects

4. Java GUI programming

4.1 The top container JFrame

Layout

Azimuth layout

flow layout

absolute layout

table layout

4.2 Child containers

JPanel

JScollPanel

4.3 Components

JLabel

JButton

JTextField

JPasswordField

5. Commonly used email information and SMS information sending API use

QQ mailbox to send messages - javax.mail

Tencent Cloud's SMS API to send SMS

Alibaba Cloud's SMS API to send SMS

<dependency>
  <groupId>com.aliyun</groupId>
  <artifactId>alibabacloud-dysmsapi20170525</artifactId>
  <version>2.0.24</version>
</dependency>