Question

What class do you use to work with random access files?

Short answer

Answer: The Java class used for working with random access files is java.io.RandomAccessFile. This class allows users to read and write data randomly within a file, such as updating specific records in a file. To use this class, create an instance with a specified file and open mode, and then use its methods (such as read() and write()) to perform random access operations on the file.

Step-by-step solution

Identify the Class

The class used to work with random access files in Java is java.io.RandomAccessFile.

Explanation of the Class

Java's java.io.RandomAccessFile class is used for reading and writing files, allowing users to read and/or modify a specified file with random access. This means you can access any part of the file without reading all the data sequentially. This class is helpful when you need to read or write data randomly within a file, such as updating specific records in a file.

Creating an Instance of the Class

To use the java.io.RandomAccessFile class, you create an instance of the class with a specified file and open mode like this: ``` RandomAccessFile raf = new RandomAccessFile("filename.txt", "rw"); ``` Here, "filename.txt" is the file we want to access and "rw" is the mode in which we want to open it (r = read, w = write).

Reading and Writing using RandomAccessFile

Once you have created an instance of the RandomAccessFile class, you can use its methods to read and write data randomly in a file. Some common methods include: - read(): reads a single byte from the file - read(byte[] b): reads up to b.length bytes from the file into the byte array - write(int b): writes a single byte to the file - write(byte[] b): writes b.length bytes to the file from the byte array Using these methods (and others provided by the class), you can perform random access operations on a file.