### Kettle summary > ETL (Extract-Transform-Load) is an ETL (Extract-Transform-Load) process for data developers

EsClientRHL EsClientRHL is a encapsulation tool that can be invoked on the ElasticSearch Java client based on SpringBoot. RestHighLeve is recommended by ElasticSearch website

In Java, there are many keywords such as final, static, this, super, public, private, protected, and so on

@[TOC] Recently there is a need to generate a new PDF according to the existing PDF template, the online information is a lot of, mainly summary of my problems and code, the first step to create a template 1 through Adobe Acrobat Pro according to the existing PDF

HashMap is one of the most commonly used data structures in our application development. What problems might occur if we use HashMap with high concurrency? 1. The result is not what we want

Strike while the iron is hot to make a recursive call, which is also the requirement of front and back end docking. The front end page can expand a row in the table, which needs to meet the multi-hierarchy relationship, so it is more convenient to solve the problem and deal with it in a recursive way

Introduce the dictionary implementation in TBOX and GLIB. To create a dictionary, use tb_

Arthas is an open source Java diagnostic tool for Alibaba that developers love. Arthas can help you solve most of your display problems when you are stuck with problems like the following!

Static proxies are the.class files of the proxy class that exist before the program is run. Dynamic proxies are created dynamically by using reflection while the program is running, without manual programming

Read about 2 minutes, Field Injection is not recommended Inspection Info: Spring Team Recommends:"