public class

StringBufferInputStream

extends InputStream
java.lang.Object
   ↳ java.io.InputStream
     ↳ java.io.StringBufferInputStream

This class is deprecated.
Use StringReader

Class Overview

A specialized InputStream that reads bytes from a String in a sequential manner.

Summary

Fields
protected String buffer The source string containing the data to read.
protected int count The total number of characters in the source string.
protected int pos The current position within the source string.
Public Constructors
StringBufferInputStream(String str)
Construct a new StringBufferInputStream with str as source.
Public Methods
synchronized int available()
Returns an estimated number of bytes that can be read or skipped without blocking for more input.
synchronized int read()
Reads a single byte from the source string and returns it as an integer in the range from 0 to 255.
synchronized int read(byte[] buffer, int offset, int length)
Reads at most length bytes from the source string and stores them in the byte array b starting at offset.
synchronized void reset()
Resets this stream to the beginning of the source string.
synchronized long skip(long n)
Skips n characters in the source string.
[Expand]
Inherited Methods
From class java.io.InputStream
From class java.lang.Object
From interface java.io.Closeable

Fields

protected String buffer

Since: API Level 1

The source string containing the data to read.

protected int count

Since: API Level 1

The total number of characters in the source string.

protected int pos

Since: API Level 1

The current position within the source string.

Public Constructors

public StringBufferInputStream (String str)

Since: API Level 1

Construct a new StringBufferInputStream with str as source. The size of the stream is set to the length() of the string.

Parameters
str the source string for this stream.
Throws
NullPointerException if str is null.

Public Methods

public synchronized int available ()

Since: API Level 1

Returns an estimated number of bytes that can be read or skipped without blocking for more input.

Note that this method provides such a weak guarantee that it is not very useful in practice.

Firstly, the guarantee is "without blocking for more input" rather than "without blocking": a read may still block waiting for I/O to complete — the guarantee is merely that it won't have to wait indefinitely for data to be written. The result of this method should not be used as a license to do I/O on a thread that shouldn't be blocked.

Secondly, the result is a conservative estimate and may be significantly smaller than the actual number of bytes available. In particular, an implementation that always returns 0 would be correct. In general, callers should only use this method if they'd be satisfied with treating the result as a boolean yes or no answer to the question "is there definitely data ready?".

Thirdly, the fact that a given number of bytes is "available" does not guarantee that a read or skip will actually read or skip that many bytes: they may read or skip fewer.

It is particularly important to realize that you must not use this method to size a container and assume that you can read the entirety of the stream without needing to resize the container. Such callers should probably write everything they read to a ByteArrayOutputStream and convert that to a byte array. Alternatively, if you're reading from a file, length() returns the current length of the file (though assuming the file's length can't change may be incorrect, reading a file is inherently racy).

The default implementation of this method in InputStream always returns 0. Subclasses should override this method if they are able to indicate the number of bytes available.

Returns
  • the estimated number of bytes available

public synchronized int read ()

Since: API Level 1

Reads a single byte from the source string and returns it as an integer in the range from 0 to 255. Returns -1 if the end of the source string has been reached.

Returns
  • the byte read or -1 if the end of the source string has been reached.

public synchronized int read (byte[] buffer, int offset, int length)

Since: API Level 1

Reads at most length bytes from the source string and stores them in the byte array b starting at offset.

Parameters
buffer the byte array in which to store the bytes read.
offset the initial position in b to store the bytes read from this stream.
length the maximum number of bytes to store in b.
Returns
  • the number of bytes actually read or -1 if the end of the source string has been reached.
Throws
IndexOutOfBoundsException if offset < 0 or length < 0, or if offset + length is greater than the length of b.
NullPointerException if b is null.

public synchronized void reset ()

Since: API Level 1

Resets this stream to the beginning of the source string.

public synchronized long skip (long n)

Since: API Level 1

Skips n characters in the source string. It does nothing and returns 0 if n is negative. Less than n characters are skipped if the end of the source string is reached before the operation completes.

Parameters
n the number of characters to skip.
Returns
  • the number of characters actually skipped.