Good blog good material record link

Preface

This article is used to record some good blogs seen on the Internet , To facilitate daily check .

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1、JavaSE relevant

1、Java Tool class ：HttpUtil（HttpClient Realization http Request , Get a response ）

2、Bigdecimal Addition, subtraction, multiplication and division 、 Compare the size 、 Round up and down and Bigdecimal Set accumulation of

3、Java Generate a payment QR code and return it to the front end

4、Java Judge whether the last character of the string is a comma , And remove the comma

2、MySQL relevant

1、 Going to the bathroom , understand MySQL Transaction isolation level

3、Spring relevant

1、@Valid and @Validated Explain in detail the usage of notes

2、@NotBlank、@NotNull 、@NotEmpty Distinguish and use

3、 solve maven pack

4、Linux relevant

1、Linux install maven

2、XShell Set copy and paste shortcuts

5、 front end

1、HTML+JS Realize web page Export pdf（ Code example ）