Flash cards
Review the key moves
What is the main idea behind Java Files?
Lesson checks
Practice each idea before moving on
Short Mimo-style checks built from this lesson's code, terms, and sequence.
Which statement best captures the main point of this lesson?
Complete the missing token from the example code.
import java.io.File; // Import the File ___Put the learning moves in the order that makes the concept easiest to apply.
File handling is an important part of any application.
Java has several methods for creating, reading, updating, and deleting files.
Java File Handling
The File class from the java.io package, allows us to work with files.
To use the File class, create an object of the class, and specify the filename or directory name: Example import java.io.File; // Import the File class File myObj = new File("filename.txt"); // Specify the filename If you don't know what a package is, read our Java Packages Tutorial . The File class has many useful methods for creating and getting information about files. For example: Method Type Description canRead() Boolean Tests whether the file is readable or not canWrite() Boolean Tests whether the file is writable or not createNewFile() Boolean Creates an empty file delete() Boolean Deletes a file exists() Boolean Tests whether the file exists getName() String Returns the name of the file getAbsolutePath() String Returns the absolute pathname of the file length() Long Returns the size of the file in bytes list() String[] Returns an array of the files in the directory mkdir() Boolean Creates a directory You will learn how to create, write, read and delete files in the next chapters:
Example
import java.io.File; // Import the File class
File myObj = new File("filename.txt"); // Specify the filenameIf you don't know what a package is, read our Java Packages Tutorial .
The File class has many useful methods for creating and getting information about files. For example:
| Method | Type | Description |
|---|---|---|
| canRead() | Boolean | Tests whether the file is readable or not |
| canWrite() | Boolean | Tests whether the file is writable or not |
| createNewFile() | Boolean | Creates an empty file |
| delete() | Boolean | Deletes a file |
| exists() | Boolean | Tests whether the file exists |
| getName() | String | Returns the name of the file |
| getAbsolutePath() | String | Returns the absolute pathname of the file |
| length() | Long | Returns the size of the file in bytes |
| list() | String[] | Returns an array of the files in the directory |
| mkdir() | Boolean | Creates a directory |
You will learn how to create, write, read and delete files in the next chapters: