StringReader

public class StringReader extends Reader

A character stream whose source is a string.

Inherited Field Summary

Public Constructor Summary

StringReader(String s)
Creates a new string reader.

Public Method Summary

void
close()
Closes the stream and releases any system resources associated with it.
void
mark(int readAheadLimit)
Marks the present position in the stream.
boolean
markSupported()
Tells whether this stream supports the mark() operation, which it does.
int
read()
Reads a single character.
int
read(char[] cbuf, int off, int len)
Reads characters into a portion of an array.
boolean
ready()
Tells whether this stream is ready to be read.
void
reset()
Resets the stream to the most recent mark, or to the beginning of the string if it has never been marked.
long
skip(long ns)
Skips the specified number of characters in the stream.

Inherited Method Summary

Public Constructors

public StringReader (String s)

Creates a new string reader.

Parameters
s String providing the character stream.

Public Methods

public void close ()

Closes the stream and releases any system resources associated with it. Once the stream has been closed, further read(), ready(), mark(), or reset() invocations will throw an IOException. Closing a previously closed stream has no effect.

public void mark (int readAheadLimit)

Marks the present position in the stream. Subsequent calls to reset() will reposition the stream to this point.

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

public boolean markSupported ()

Tells whether this stream supports the mark() operation, which it does.

Returns
  • true if and only if this stream supports the mark operation.

public int read ()

Reads a single character.

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

public int read (char[] cbuf, int off, int len)

Reads characters into a portion of an array.

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

public boolean ready ()

Tells whether this stream is ready to be read.

Returns
  • True if the next read() is guaranteed not to block for input
Throws
IOException If the stream is closed

public void reset ()

Resets the stream to the most recent mark, or to the beginning of the string if it has never been marked.

Throws
IOException If an I/O error occurs

public long skip (long ns)

Skips the specified number of characters in the stream. Returns the number of characters that were skipped.

The ns parameter may be negative, even though the skip method of the Reader superclass throws an exception in this case. Negative values of ns cause the stream to skip backwards. Negative return values indicate a skip backwards. It is not possible to skip backwards past the beginning of the string.

If the entire string has been read or skipped, then this method has no effect and always returns 0.

Parameters
ns The number of characters to skip
Returns
  • The number of characters actually skipped
Throws
IOException If an I/O error occurs