将括号放在文件名周围

Question

This is a correction of my previous question Put brackets around filename for Excel formula

My project is based on Apache POI.I'm trying to use a formula on a cell. My formula is as follows.

sheet7.createRow(0).createCell(0).setCellFormula("+'C:\\Users\\Desktop\\[Test.xlsx]Average_Graph'!A2");

Im using a JFileChooser, which allows users to select the file. Therefore the filepath will be changed every time the program is used.

From the JFileChooser, I'm getting a filepath as follows.

 String filepath= "C:\\Users\\Desktop\\Sheet.xlsx"`

In order to work the formula correctly, the filepath should be in following format.

"C:\\Users\\Desktop\\[Sheet.xlsx]"

How Can I Change the string which I'm getting from the JFileCHooser to run the formula correctly?

In previous question, I mistakenly typed C:\\Users\\Desktop[Sheet.xlsx] instead of C:\\Users\\Desktop\\[Sheet.xlsx] The answers gave me the output which i've mentioned. But I need the Output as C:\\Users\\Desktop\\[Sheet.xlsx]

Please help.

Answer 1

If you want to solve this by directly altering the file path, you may use String#replaceAll :

String filepath = "C:\\Users\\Desktop\\Sheet.xlsx";
filepath = filepath.replaceAll("(?<=\\\\)([^\\\\]+)$", "[$1]");
System.out.println(filepath);

C:\Users\Desktop\[Sheet.xlsx]

Demo

Answer 2

File names won't have \\backslashes in them, so we can assume that our filename begins after the last backslash and ends at the end of the string.

We can use this:

String filepath = "C:\\Users\\Desktop\\Sheet.xlsx";
String dir = filepath.substring(0, filepath.lastIndexOf("\\"+1));
String filename = filepath.substring(filepath.lastIndexOf("\\"+1));

filepath = dir + "[" + filename + "]";

Or a shorter version:

String filepath = "C:\\Users\\Desktop\\Sheet.xlsx";
filepath =  filepath.substring(0, filepath.lastIndexOf("\\"+1)) +
            "[" + filepath.substring(filepath.lastIndexOf("\\"+1)) + "]";