java.io
Class StringReader

java.lang.Object
  extended byjava.io.Reader
      extended byjava.io.StringReader

public class StringReader
extends Reader

A character stream whose source is a string.

Since:
JDK1.1
Author:
Mark Reinhold

Field Summary
private  int length
           
private  int mark
           
private  int next
           
private  String str
           
 
Fields inherited from class java.io.Reader
lock
 
Constructor Summary
StringReader(String s)
          Create a new string reader.
 
Method Summary
 void close()
          Close the stream.
private  void ensureOpen()
          Check to make sure that the stream has not been closed
 void mark(int readAheadLimit)
          Mark the present position in the stream.
 boolean markSupported()
          Tell whether this stream supports the mark() operation, which it does.
 int read()
          Read a single character.
 int read(char[] cbuf, int off, int len)
          Read characters into a portion of an array.
 boolean ready()
          Tell whether this stream is ready to be read.
 void reset()
          Reset the stream to the most recent mark, or to the beginning of the string if it has never been marked.
 long skip(long ns)
          Skip characters.
 
Methods inherited from class java.io.Reader
read
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Field Detail

str

private String str

length

private int length

next

private int next

mark

private int mark
Constructor Detail

StringReader

public StringReader(String s)
Create a new string reader.

Parameters:
s - String providing the character stream.
Method Detail

ensureOpen

private void ensureOpen()
                 throws IOException
Check to make sure that the stream has not been closed

Throws:
IOException

read

public int read()
         throws IOException
Read a single character.

Overrides:
read in class Reader
Returns:
The character read, or -1 if the end of the stream has been reached
Throws:
IOException - If an I/O error occurs

read

public int read(char[] cbuf,
                int off,
                int len)
         throws IOException
Read characters into a portion of an array.

Specified by:
read in class Reader
Parameters:
cbuf - Destination buffer
off - Offset at which to start writing characters
len - Maximum number of characters to read
Returns:
The number of characters read, or -1 if the end of the stream has been reached
Throws:
IOException - If an I/O error occurs

skip

public long skip(long ns)
          throws IOException
Skip characters.

Overrides:
skip in class Reader
Parameters:
ns - The number of characters to skip
Returns:
The number of characters actually skipped
Throws:
IOException - If an I/O error occurs

ready

public boolean ready()
              throws IOException
Tell whether this stream is ready to be read.

Overrides:
ready in class Reader
Returns:
True if the next read() is guaranteed not to block for input
Throws:
IOException - If the stream is closed

markSupported

public boolean markSupported()
Tell whether this stream supports the mark() operation, which it does.

Overrides:
markSupported in class Reader
Returns:
true if and only if this stream supports the mark operation.

mark

public void mark(int readAheadLimit)
          throws IOException
Mark the present position in the stream. Subsequent calls to reset() will reposition the stream to this point.

Overrides:
mark in class Reader
Parameters:
readAheadLimit - Limit on the number of characters that may be read while still preserving the mark. Because the stream's input comes from a string, there is no actual limit, so this argument must not be negative, but is otherwise ignored.
Throws:
IllegalArgumentException - If readAheadLimit is < 0
IOException - If an I/O error occurs

reset

public void reset()
           throws IOException
Reset the stream to the most recent mark, or to the beginning of the string if it has never been marked.

Overrides:
reset in class Reader
Throws:
IOException - If an I/O error occurs

close

public void close()
Close the stream.

Specified by:
close in class Reader