Get current working directory

Get current working directory
The current working directory means the root folder of your current Java project, it can be retrieved by using the following system property function.
There are two ways to get current working directory.
String workingDir = System.getProperty("user.dir");
FileSystems.getDefault().getPath("").toAbsolutePath().toString()

Create directory

1. Create Directory – Java NIO
1.1 We can use Files.createDirectory to create a directory.

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  If the parent directories not exist, throws NoSuchFileException.
  
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  If the directory exists, throws FileAlreadyExistsException.
  
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  If IO errors, throws IOException.
  

1.2 We can use Files.createDirectories creates a directory including all nonexistent parent directories.

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  If the parent directories not exist, create it first.
  
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  If the directory exists, no exception thrown.
  
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  If IO errors, throws IOException
  

2. Create Directory – Legacy IO

For legacy IO java.io.File, the similar methods are file.mkdir() to create a directory, and file.mkdirs() to create a directory including all nonexistent parent directories.
Both file.mkdir() and file.mkdirs() returns a boolean, true if success to create the directory, fail otherwise, no exception thrown.

8. Learn Data Structures and Algorithms

What is a Stack?

A stack is an ordered list in which insertion and deletion are done at one end, called a top. The last element inserted is the first one to be deleted. Hence, it is called the Last in First out (LIFO) or First in Last out (FILO) list.
Stack – bu tartiblangan ro’yxat hisoblanadi.

Stack Operations

The following operations make a stack an Abstract Data Type.

Lets first familiar with few concepts that are used in stack implementation.

Stack Concepts

1.