1. Description
2. Field Summary
3. Constructor Summary
4. Method Summary
   1. Methods declared in class Reader
   2. Methods declared in class Object
5. Constructor Details
   1. BufferedReader(Reader, int)
   2. BufferedReader(Reader)
6. Method Details
   1. read()
   2. read(char[], int, int)
   3. readLine()
   4. ready()
   5. markSupported()
   6. mark(int)
   7. reset()
   8. close()
   9. lines()

• Field Summary

  Fields declared in class Reader

  lock

  Modifier and Type

  Field

  Description

  protected Object

  lock

  The object used to synchronize operations on this stream.

• Constructor Summary

  Constructors
  Constructor

  Description

  BufferedReader(Reader in)

  Creates a buffering character-input stream that uses a default-sized input buffer.

  BufferedReader(Reader in, int sz)

  Creates a buffering character-input stream that uses an input buffer of the specified size.

• Method Summary

  All MethodsInstance MethodsConcrete Methods

  Modifier and Type

  Method

  Description

  void

  close()

  Closes the stream and releases any system resources associated with it.

  Stream<String>

  lines()

  Returns a Stream, the elements of which are lines read from this BufferedReader.

  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.

  String

  readLine()

  Reads a line of text.

  boolean

  ready()

  Tells whether this stream is ready to be read.

  void

  reset()

  Resets the stream to the most recent mark.

  Methods declared in class Reader

  nullReader, of, read, read, readAllAsString, readAllLines, skip, transferTo

  Modifier and Type

  Method

  Description

  static Reader

  nullReader()

  Returns a new Reader that reads no characters.

  static Reader

  of(CharSequence cs)

  Returns a Reader that reads characters from a CharSequence.

  int

  read(char[] cbuf)

  Reads characters into an array.

  int

  read(CharBuffer target)

  Attempts to read characters into the specified character buffer.

  String

  readAllAsString()

  Reads all remaining characters into a string.

  List<String>

  readAllLines()

  Reads all remaining characters as lines of text.

  long

  skip(long n)

  Skips characters.

  long

  transferTo(Writer out)

  Reads all characters from this reader and writes the characters to the given writer in the order that they are read.

  Methods declared in class Object

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

  Modifier and Type

  Method

  Description

  protected Object

  clone()

  Creates and returns a copy of this object.

  boolean

  equals(Object obj)

  Indicates whether some other object is "equal to" this one.

  protected void

  finalize()

  Deprecated, for removal: This API element is subject to removal in a future version.

  Finalization is deprecated and subject to removal in a future release.

  final Class<?>

  getClass()

  Returns the runtime class of this Object.

  int

  hashCode()

  Returns a hash code value for this object.

  final void

  notify()

  Wakes up a single thread that is waiting on this object's monitor.

  final void

  notifyAll()

  Wakes up all threads that are waiting on this object's monitor.

  String

  toString()

  Returns a string representation of the object.

  final void

  wait()

  Causes the current thread to wait until it is awakened, typically by being notified or interrupted.

  final void

  wait(long timeoutMillis)

  Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.

  final void

  wait(long timeoutMillis, int nanos)

  Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.

• Constructor Details

  • BufferedReader

    public BufferedReader(Reader in, int sz)

    Creates a buffering character-input stream that uses an input buffer of the specified size.

    Parameters: in - A Reader sz - Input-buffer size Throws: IllegalArgumentException - If sz <= 0

  • BufferedReader

    public BufferedReader(Reader in)

    Creates a buffering character-input stream that uses a default-sized input buffer.

    Parameters: in - A Reader

• Method Details

  • read

    public int read() throws IOException

    Reads a single character.

    Overrides: read in class Reader Returns: The character read, as an integer in the range 0 to 65535 (0x00-0xffff), 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.

    This method implements the general contract of the corresponding read method of the Reader class. As an additional convenience, it attempts to read as many characters as possible by repeatedly invoking the read method of the underlying stream. This iterated read continues until one of the following conditions becomes true:

    • The specified number of characters have been read,
    • The read method of the underlying stream returns -1, indicating end-of-file, or
    • The ready method of the underlying stream returns false, indicating that further input requests would block.

    If the first read on the underlying stream returns -1 to indicate end-of-file then this method returns -1. Otherwise this method returns the number of characters actually read.

    Subclasses of this class are encouraged, but not required, to attempt to read as many characters as possible in the same fashion.

    Ordinarily this method takes characters from this stream's character buffer, filling it from the underlying stream as necessary. If, however, the buffer is empty, the mark is not valid, and the requested length is at least as large as the buffer, then this method will read characters directly from the underlying stream into the given array. Thus redundant BufferedReaders will not copy data unnecessarily.

    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

  • readLine

    public String readLine() throws IOException

    Reads a line of text. A line is considered to be terminated by any one of a line feed ('\n'), a carriage return ('\r'), a carriage return followed immediately by a line feed, or by reaching the end-of-file (EOF).

    Returns: A String containing the contents of the line, not including any line-termination characters, or null if the end of the stream has been reached without reading any characters Throws: IOException - If an I/O error occurs See Also:

    • Files.readAllLines(Path, Charset)

  • ready

    public boolean ready() throws IOException

    Tells whether this stream is ready to be read. A buffered character stream is ready if the buffer is not empty, or if the underlying character stream is ready.

    Overrides: ready in class Reader Returns: True if the next read() is guaranteed not to block for input, false otherwise. Note that returning false does not guarantee that the next read will block. Throws: IOException - If an I/O error occurs

  • 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 attempt to 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. An attempt to reset the stream after reading characters up to this limit or beyond may fail. A limit value larger than the size of the input buffer will cause a new buffer to be allocated whose size is no smaller than limit. Therefore large values should be used with care. 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.

    Overrides: reset in class Reader Throws: IOException - If the stream has never been marked, or if the mark has been invalidated

  • close

    public void close() throws IOException

    Description copied from class: Reader

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

    Specified by: close in interface AutoCloseable Specified by: close in interface Closeable Specified by: close in class Reader Throws: IOException - If an I/O error occurs

  • lines

    public Stream<String> lines()

    Returns a Stream, the elements of which are lines read from this BufferedReader. The Stream is lazily populated, i.e., read only occurs during the terminal stream operation.

    The reader must not be operated on during the execution of the terminal stream operation. Otherwise, the result of the terminal stream operation is undefined.

    After execution of the terminal stream operation there are no guarantees that the reader will be at a specific position from which to read the next character or line.

    If an IOException is thrown when accessing the underlying BufferedReader, it is wrapped in an UncheckedIOException which will be thrown from the Stream method that caused the read to take place. This method will return a Stream if invoked on a BufferedReader that is closed. Any operation on that stream that requires reading from the BufferedReader after it is closed, will cause an UncheckedIOException to be thrown.

    Returns: a Stream<String> providing the lines of text described by this BufferedReader Since: 1.8

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