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Java Exception Handling MCQ Test

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I/O Streams

 Input/Output Streams in Java


In Java, streams represent a sequence of data. Input streams are used for reading data from a source, while output streams are used for writing data to a destination.


Types of Streams:


1. Byte Streams:

   - Operate on bytes.

   - Suitable for binary data.

   - `InputStream` and `OutputStream` are the abstract classes for byte streams.


2. Character Streams:

   - Operate on characters, internally converting them to bytes.

   - Suitable for text data.

   - `Reader` and `Writer` are the abstract classes for character streams.


Commonly Used Byte Streams:


- `FileInputStream` and `FileOutputStream`: For reading/writing from/to files.

- `ByteArrayInputStream` and `ByteArrayOutputStream`: For reading/writing to byte arrays.

- `DataInputStream` and `DataOutputStream`: For reading/writing primitive data types.

- `ObjectInputStream` and `ObjectOutputStream`: For reading/writing Java objects.


Commonly Used Character Streams:


- `FileReader` and `FileWriter`: For reading/writing text files.

- `BufferedReader` and `BufferedWriter`: For reading/writing text with buffering for efficiency.

- `InputStreamReader` and `OutputStreamWriter`: For bridging byte and character streams.


Basic Usage Pattern:


1. Opening Streams:

   - Create a stream object by passing the appropriate source or destination as a parameter to its constructor.


2. Reading/Writing Data:

   - Use methods like `read()`, `write()`, `readLine()`, `writeLine()`, etc., to perform I/O operations.


3. Closing Streams:

   - Always close streams after use to release system resources.

   - Use `close()` method or utilize try-with-resources statement for automatic resource management.


Example:


import java.io.*;

public class StreamExample {

    public static void main(String[] args) {

        try (FileInputStream fis = new FileInputStream("input.txt");

             FileOutputStream fos = new FileOutputStream("output.txt")) {

            

            int byteRead;

            while ((byteRead = fis.read()) != -1) {

                fos.write(byteRead);

            }

        } catch (IOException e) {

            e.printStackTrace();

        }

    }

}



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