Check out example codes for "java create folder". It will help you in understanding the concepts better.

Code Example 1

new File("pathToFile").mkdir();

Code Example 2

package com.mkyong.file;

import java.io.File;

public class CreateDirectoryExample {

    public static void main(String[] args) {

        File file = new File("C:\\Directory1");
        if (!file.exists()) {
            if (file.mkdir()) {
                System.out.println("Directory is created!");
            } else {
                System.out.println("Failed to create directory!");
            }
        }

        File files = new File("C:\\Directory2\\Sub2\\Sub-Sub2");
        if (!files.exists()) {
            if (files.mkdirs()) {
                System.out.println("Multiple directories are created!");
            } else {
                System.out.println("Failed to create multiple directories!");
            }
        }

    }

}

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