What is the purpose of the DataInputStream class in Java?Question 4Answera.To read primitive data types from a fileb.To read text from a character-based input streamc.To read serialized objects from a filed.To read binary data from a file

The purpose of the DataInputStream class in Java is to read primitive data types from an input stream in a portable way. It is a filter stream that is often used in combination with a FileInputStream to read data from a file. It can also be used with any other input stream to read data from various sources like network connections, memory, etc.

Here is a step-by-step explanation:

1. DataInputStream is a class in Java that is used for reading primitive data types from an input stream. It is part of the java.io package.

2. It is a filter input stream, which means it is used in combination with another input stream. It cannot read data directly from a file or network connection, but it can read data from another input stream that is connected to the file or network connection.

3. The main purpose of DataInputStream is to provide methods for reading the Java primitive data types (boolean, char, byte, short, int, long, float, and double) from an input stream in a portable way. This means that the data can be read on any machine, regardless of the machine's architecture.

4. The methods provided by DataInputStream for reading primitive data types are readBoolean(), readChar(), readByte(), readShort(), readInt(), readLong(), readFloat(), and readDouble(). These methods read the data in binary format, which is the format used by the Java virtual machine.

5. In addition to reading primitive data types, DataInputStream also provides the method readUTF() for reading strings that have been encoded using the UTF-8 encoding.

6. To read data from a file using DataInputStream, you would typically use a FileInputStream to connect to the file, and then create a DataInputStream that reads from the FileInputStream.