How to trim String directory in java

Question

I am trying to trim my directory which is in string format in java . I only want images/filename and want to remove directory before images.

Answer 1

Split

This answer covers both forwardslashed directories and backslash directories.

Sample Input:

C:/hello/myAwesomeImage.png
C:\hello\myAwesomeImage.png

Forwardslashes

String [] myFile = "C:/hello/myAwesomeImage.png".split("/"); // split it
String myFileName = myFile[myFile.length - 1]; // Extract filename

Backslashes

String [] myFile = "C:\hello\myAwesomeImage.png".split("\\"); // split it
String myFileName = myFile[myFile.length - 1]; // Extract filename

Output: "myAwesomeImage.png"

Alternatively, if you don't want to split...

RegEx

Backslash + No Extension

String myFile = "C:\\hello\\myAwesomeImage.png".matches("[ \\w-]+?(?=\\.)");

Output: "myAwesomeImage"

Backslash + Extension

 String myFile = "C:\\hello\\myAwesomeImage.png".matches("[ \w-]+\....");

Output: "myAwesomeImage.png"

Forwardslash + Extension

String myFile = "C:/hello/myAwesomeImage.png".matches("[^\/]+(?=\.*$)");

Output: "myAwesomeImage.png"

Forwardslash + No Extension

String myFile = "C:/hello/myAwesomeImage.png".matches("[^\/]+(?=\..*$)");

Output: "myAwesomeImage"

Answer 2

Java has a powerful built-in File API. java.io.File is particularly useful.

I would recommend using this rather than string manipulation, Advantages include portability across operating systems which may use / or .

File myFile = new File("C:/hello/myAwesomeImage.png");
System.out.println(myFile.getName());
System.out.println(myFile.getParentFile().getName());
System.out.println(myFile.getParentFile().getParent());

Output

myAwesomeImage.png
hello
C: