Swagger can help you generate document for your restful API. This blog will show you how to use it. I assume that you have known how to use Spring Boot. The structure of example project is like following.
Use jsonassert framework to compare two json are same or not. It only compare the content of them. The example code is here;
Use \d or \d+ in psql command to show all tables. \d+ will show additional detail of tables;
The annotation @ResponseBody can help you convert object to json. Sometimes if the field of object is null the json returned like following.
Use set command to list all environment variables. They are like following in my computer.
Use du command to show the size of folder. Before testing this command we will create a directory and a file.
In PosgreSQL there are several ways to switch database.
In PostgreSQL there are two ways to list all databases.
When I start tomcat to deploy my application I got the error message like following.
It's easy to use Apache POI read excel file. Let's say you have an excel file. The path of it is D:\test.xlsx. The content is like following.
We can convert list to map easily in Java8 by using stream. The sample code is like following.
Executors.newFixedThreadPool(3) method will create a thread pool with only 3 threads. When we put Runnable or Callable object into the thread pool. The thread pool will create new thread for running task. When the number of threads equals the pool size the new task will be queued. The code below may help you have a better understanding of the the method newFixedThreadPool().
There are several ways to show indexes for a table in MySQL. Let's say you have create the table in your database. The schema of table is here.
Executors.newCachedThreadPool() method will create a thread pool which core pool size is 0 and max pool size is Integer.MAX_VALUE. The detail of constructor function is here:
This series of blog describes mainly how to use common classes of JDK.