Android RandomAccessFile Guide: Read & Write Files

In Android, the RandomAccessFile class is used to read and write the contents of a file, allowing you to position to any location in the file for read and write operations. Here are some common methods used with RandomAccessFile:

1. Create a RandomAccessFile object:

RandomAccessFile randomAccessFile = new RandomAccessFile("file.txt", "rw");

The first parameter is the file path, and the second parameter is the mode, with “rw” indicating read and write mode.

1. Write data to file.

randomAccessFile.write("Hello, World!".getBytes());

1. Locate the specified position of the file.

randomAccessFile.seek(5); // 定位到文件的第5个字节位置

1. Reading the contents of the file.

byte[] buffer = new byte[10];
randomAccessFile.read(buffer);
String content = new String(buffer);

1. Close the RandomAccessFile object.

randomAccessFile.close();

After using RandomAccessFile, make sure to call the close() method to close the file. Always remember to handle exceptions when using RandomAccessFile, such as file not found or permission denied.