Introduction
The Java.io InputStream is one of the supper class to all types of input streams in java.io package. Generally the input stream acts as a source to the data like file or connection.
Conceptual
figure
Description
The methods inherited mainly from the InputStream class to subclasses are read(), mark() and reset(). All the subclasses to input stream supports all this methods.
Declaration
Java.io InputStream class is declared below:
Public abstract class InputStream extends Object implements closeable Table
| Constructor | Description |
|---|---|
| InputStream() | The function of this constructor is to create the input stream instance. |
Table
| Method | Description |
|---|---|
| void close () | The function of this method is to close the present stream and associated to input stream systems resources are released without any impact. |
| Long skip (long m) | The function of this method is to skip the text or characters in this stream of ' m ' bytes. |
| Boolean markSupported () | The function of this method is to check the represented mark method is supported by this stream or not |
| int read(byte[] b, int off, int n) | By using this method it reads the data up to 'n' bytes from the input stream to an array of the bytes. |
Description
From the following classes, methods are inherited to input stream class.
- Java.io.Object
Examples
Usage of void close() method.
[c]import java.io.FileInputStream;
import java.io.InputStream;
public class InputStream
{
public static void main(String[] args) throws Exception
{
InputStream is = null;
int i=0;
try{
// creating a new input stream
is = new FileInputStream("C://test.txt");
// To invoke available
i = is.available();
// The number of bytes which are available are printed
System.out.println(i);
// It releases any system resources associated with this stream
is.close();
// It throws I/O exception on available() invocation
i = is.available();
System.out.println(i);
}catch(Exception e)
{
// If any I/O error occurs
System.out.print("input stream is closed");
}finally
{
// releases all the system resources associated with this stream
if(is!=null)
is.close();
}
}
}[/c]
Output
The result will be as follows.
[c]input stream is closed[/c]
Usage of Long skpip (Long n) method.
[c]import java.io.FileInputStream;
import java.io.InputStream;
public class InputStream
{
public static void main(String[] args) throws Exception
{
InputStream is = null;
int i ;
char c;
try{
// creating a new input stream
is = new FileInputStream("D://test.txt");
while((i=is.read())!=-1)
{
// To convert integer to character
c=(char)i;
// To print character
System.out.println("Read Character: "+c);
// To skip one byte
is.skip(1);
}
}catch(Exception e)
{
// if any I/O error occurs
e.printStackTrace();
}finally
{
// releases all the system resources associated with this stream
if(is!=null)
is.close();
}
}
}[/c]
Output
Following is the result will be displayed.
[c]
Read Character: o
Read Character: s
Read Character: c
Read Character: m[/c]
Key Points
-
<liThe Java.io InputStream is one of the supper class to all types of input streams in java.io package.
- Generally the Java.io InputStream acts as a source to the data like file or connection.
- The methods inherited mainly from the InputStream class to subclasses are read(), mark() and reset().