Chapter 11
The java.io Package

StringBufferInputStream

Name

Synopsis

Class Name:

java.io.StringBufferInputStream

Superclass:

java.io.InputStream

Immediate Subclasses:

None

Interfaces Implemented:

None

Availability:

Deprecated as of JDK 1.1

Description

The StringBufferInputStream class represents a byte stream whose data source is a String. This class is similar to the ByteArrayInputStream class, which uses a byte array as its data source.

StringBufferInputStream is deprecated as of JDK 1.1 because it does not correctly convert characters to bytes. The StringReader class should now be used to create a character stream from aString.

Class Summary

public class java.io.StringBufferInputStream extends java.io.InputStream {
  // Variables
  protected String buffer;
  protected int count;
  protected int pos;
  // Constructor
  public StringBufferInputStream(String s);
  // Instance Methods
  public synchronized int available();
  public synchronized int read();
  public synchronized int read(byte[] b, int off, int len); 
  public synchronized void reset();
  public synchronized long skip(long n); 
}

Variables

buffer

protected String buffer

Description: The buffer that stores the data for the input stream.

count

protected int count

Description: The size of the buffer, or in other words, the length of the string.

pos

protected int pos

Description: The current stream position.

Constructors

StringBufferInputStream

public StringBufferInputStream(String s)

Parameters

s: The String to use.

Description

This constructor creates a StringBufferInputStream that uses the given String as its data source. Note that the data is not copied, so changes made to the String affect the data that the StringBufferInputStream returns.

Instance Methods

available

public synchronized int available()

Returns

The number of bytes remaining in the string.

Overrides

InputStream.available()

Description

This method returns the number of bytes that are left in the string. This is the length of the string, count, minus the current stream position, pos.

read

public synchronized int read()

Returns

The next byte of data or -1 if the end of the string is encountered.

Overrides

InputStream.read()

Description

This method returns the next byte from the string. The method takes the next character from the string and returns the low eight bits of that character as a byte, which is not the correct way to convert characters into bytes. The method cannot block.

public synchronized int read(byte b[], int off, int len)

Parameters

b

An array of bytes to be filled from the stream.

off

An offset into the byte array.

len

The number of bytes to read.

Returns

The actual number of bytes read or -1 if the end of the string is encountered immediately.

Overrides

InputStream.read(byte[], int, int)

Description

This method copies bytes from the internal buffer into the given array b, starting at index off and continuing for len bytes. The method takes each character from the string and returns the low eight bits of that character as a byte, which is not the correct way to convert characters into bytes.

reset

public synchronized void reset()

Overrides

InputStream.reset()

Description

This method sets the position of the StringBufferInputStream back to the beginning of the internal buffer.

skip

public synchronized long skip(long n)

Parameters

n: The number of bytes to skip.

Returns

The actual number of bytes skipped.

Overrides

InputStream.skip()

Description

This method skips n bytes of the string. If you try to skip past the end of the string, the stream is positioned at the end of the string.

Inherited Methods

Method	Inherited From	Method	Inherited From
`clone()`	`Object`	`close()`	`InputStream`
`equals(Object)`	`Object`	`finalize()`	`Object`
`getClass()`	`Object`	`hashCode()`	`Object`
`mark(int)`	`InputStream`	`markSupported()`	`InputStream`
`notify()`	`Object`	`notifyAll()`	`Object`
`read(byte[])`	`InputStream`	`toString()`	`Object`
`wait()`	`Object`	`wait(long)`	`Object`
`wait(long, int)`	`Object`