Question

Compare and contrast InputStream/OutputStream based file I/O to Scanner/Printwriter based file I/O:

Answer 1

InputStream/OutputStream based File I/O

A stream can be defined as a sequence of data. There are two kinds of Streams −

• InputStream − The InputStream is used to read data from a source.

• OutputStream − The OutputStream is used for writing data to a destination
  
  Java byte streams are used to perform input and output of 8-bit bytes. Though there are many classes related to byte streams but for File I/O there are FileInputStream and FileOutputStream.

Scanner/PrintWriter based File I/O

The Scanner class is available in Java 5 (JDK 1.5). It provides methods to convert text into appropriate Java types (integer, float, etc). A scanner splits text into a succession of tokens (text representations of data values) according to specific rules.

For example, in the String object "ab*cd 12.34 253", "ab*cd" is a String token, "12.34" is a double token and "253" is an integer token.

Objects of type Scanner are useful for breaking down formatted input into tokens and translating individual tokens according to their data type.

Selected Constructors:
public Scanner(String s): Constructs a new Scanner that produces values scanned from the specified string.
public Scanner(InputStream source): Constructs a new Scanner that produces values scanned from the specif
Selected Methods:
public String nextLine(): Scan the next line of input
public int nextInt(): Scan the next integer
public double nextDouble(): Scan the next double

PrintWiter

public class PrintWriter
extends Writer
Prints formatted representations of objects to a text-output stream. This class implements all of the print methods found in PrintStream. It does not contain methods for writing raw bytes, for which a program should use unencoded byte streams.

Some differences are:-

InputStream/OutputStream based file I/O	Scanner/PrintWriter based file I/O
It provides a convenient means for handling input and output of bytes.	A scanner uses white space to separate tokens. (White space characters include blanks, tabs, and line terminators of character format and PrintWriter is used where it is required to write data in characters.
Throws checked Exception	Doesn't throw checked exceptions
It can read chars, char arrays, and lines	Difficult to read single characters
It provides read() : reads byte of data and write() : Writes byte of data.	It provides public String nextLine(): Scan the next line of input public int nextInt(): Scan the next integer public double nextDouble(): Scan the next double
It is available from beginning of Java	It came in JDK 1.5
These used to perform input and output of 8-bit bytes	These are used to perform input and output for 16-bit unicode.
When we want to send data on network,we use byte stream .	It is suitable for local machine operations..