1. Description
2. Field Summary
3. Constructor Summary
4. Method Summary
5. Constructor Details
   1. StringReader(String)
6. Method Details
   1. read()
   2. read(char[], int, int)
   3. skip(long)
   4. ready()
   5. markSupported()
   6. mark(int)
   7. reset()
   8. close()

All Implemented Interfaces:

Closeable, AutoCloseable, Readable

• Field Summary

  Fields declared in class java.io.Reader

  lock

• Constructor Summary

  Constructors
  Constructor

  Description

  StringReader(String s)

  Creates a new string reader.

• Method Summary

  All MethodsInstance MethodsConcrete Methods

  Modifier and Type

  Method

  Description

  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 n)

  Skips characters.

  Methods declared in class java.io.Reader

  nullReader, of, read, read, transferTo

  Methods declared in class java.lang.Object

  clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

• Constructor Details

  • StringReader

    public StringReader(String s)

    Creates a new string reader.

    Parameters:

    s - String providing the character stream.

• Method Details

  • read

    public int read() throws IOException

    Reads 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

    Reads characters into a portion of an array.

    If len is zero, then no characters are read and 0 is returned; otherwise, there is an attempt to read at least one character. If no character is available because the stream is at its end, the value -1 is returned; otherwise, at least one character is read and stored into cbuf.

    Specified by:

    read in class Reader

    Parameters:

    cbuf - Destination buffer

    off - Offset at which to start storing 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:

    IndexOutOfBoundsException - If off is negative, or len is negative, or len is greater than cbuf.length - off

    IOException - If an I/O error occurs

  • skip

    public long skip(long n) throws IOException

    Skips characters. If the stream is already at its end before this method is invoked, then no characters are skipped and zero is returned.

    The n parameter may be negative, even though the skip method of the Reader superclass throws an exception in this case. Negative values of n 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.

    Overrides:

    skip in class Reader

    Parameters:

    n - 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

    Tells 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()

    Tells 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

    Marks 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 < 0

    IOException - If an I/O error occurs

  • reset

    public void reset() throws IOException

    Resets 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()

    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. This method will block while there is another thread blocking on the reader.

    Specified by:

    close in interface AutoCloseable

    Specified by:

    close in interface Closeable

    Specified by:

    close in class Reader

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