There are a lot of APIs regarding files and IO in Java. Some of the basics will be discussed here.
- BufferedInputStream
- BufferedOutputStream
- DataInputStream
- DataOutputStream
First let us differentiate all these.
1. BufferedInputStream : kind of inputStream that buffers the input data in order to optimize the speed access to the data.
2. BufferedOutputStream : kind of outputStream that buffers bytes.
3. DataInputStream : is a kind of InputStream used to read data as primitive data types from an underlying input stream.
4.DataOutputStream : kinf of outputStream that allows user to write data as primitive data types.
Examples:
Using DataInputStream in reading boolean data type
import java.io.DataInputStream;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
public class DataInputStreamReadBoolean {
public static void main(String[] args){
String file = "C://tutorialpointph//booleanfile.txt";
try
{
//Get the file to read using BufferedInputStream
FileInputStream fin = new FileInputStream(file);
/*
* DataInputStream(InputStream in) constructor.
*/
DataInputStream din = new DataInputStream(fin);
/*
* readBoolean() method reads a byte from the file
* and return true if the byte is not zero and
* false if byte is zero.
*/
boolean b = din.readBoolean();
System.out.println("Value on text file : " + b);
din.close();
}
catch(FileNotFoundException e)
{
System.out.println("File not found on path : " + e);
}
catch(IOException ie)
{
System.out.println("Exception while reading : " + ie);
}
}
}
Using DataInputStream in reading byte data type
import java.io.DataInputStream;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
public class DataInputStreamReadByte {
public static void main(String[] args){
String file = "C://tutorialpointph//bytefile.txt";
try
{
//Get the file to read using BufferedInputStream
FileInputStream fin = new FileInputStream(file);
/*
* DataInputStream(InputStream in) constructor.
*/
DataInputStream din = new DataInputStream(fin);
/*
* readByte() method reads a byte from the file
*/
byte b = din.readByte();
System.out.println("Value on text file : " + b);
din.close();
}
catch(FileNotFoundException e)
{
System.out.println("File not found on path : " + e);
}
catch(IOException ie)
{
System.out.println("Exception while reading : " + ie);
}
}
}
Using DataInputStream in reading int data type
import java.io.DataInputStream;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
public class DataInputStreamReadInt {
public static void main(String[] args){
String file = "C://tutorialpointph//intfile.txt";
try
{
//Get the file to read using BufferedInputStream
FileInputStream fin = new FileInputStream(file);
/*
* DataInputStream(InputStream in) constructor.
*/
DataInputStream din = new DataInputStream(fin);
/*
* readInt() method reads an integer primitive
* from the file
*/
int i = din.readInt();
System.out.println("Value on text file : " + i);
din.close();
}
catch(FileNotFoundException e)
{
System.out.println("File not found on path : " + e);
}
catch(IOException ie)
{
System.out.println("Exception while reading : " + ie);
}
}
}
