1. Description
2. Field Summary
3. Constructor Summary
4. Method Summary
5. Constructor Details
   1. LineNumberReader(Reader)
   2. LineNumberReader(Reader, int)
6. Method Details
   1. setLineNumber(int)
   2. getLineNumber()
   3. read()
   4. read(char[], int, int)
   5. readLine()
   6. mark(int)
   7. reset()

• 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

  LineNumberReader(Reader in)

  Create a new line-numbering reader, using the default input-buffer size.

  LineNumberReader(Reader in, int sz)

  Create a new line-numbering reader, reading characters into a buffer of the given size.

• Method Summary

  All MethodsInstance MethodsConcrete Methods

  Modifier and Type

  Method

  Description

  int

  getLineNumber()

  Get the current line number.

  void

  mark(int readAheadLimit)

  Mark the present position in the stream.

  int

  read()

  Read a single character.

  int

  read(char[] cbuf, int off, int len)

  Reads characters into a portion of an array.

  String

  readLine()

  Read a line of text.

  void

  reset()

  Reset the stream to the most recent mark.

  void

  setLineNumber(int lineNumber)

  Set the current line number.

  Methods declared in class BufferedReader

  close, lines, markSupported, ready

  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.

  boolean

  markSupported()

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

  boolean

  ready()

  Tells whether this stream is ready to be read.

  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

  • LineNumberReader

    public LineNumberReader(Reader in)

    Create a new line-numbering reader, using the default input-buffer size.

    Parameters: in - A Reader object to provide the underlying stream

  • LineNumberReader

    public LineNumberReader(Reader in, int sz)

    Create a new line-numbering reader, reading characters into a buffer of the given size.

    Parameters: in - A Reader object to provide the underlying stream sz - An int specifying the size of the buffer

• Method Details

  • setLineNumber

    public void setLineNumber(int lineNumber)

    Set the current line number.

    Parameters: lineNumber - An int specifying the line number See Also:

    • getLineNumber()

  • getLineNumber

    public int getLineNumber()

    Get the current line number.

    Returns: The current line number See Also:

    • setLineNumber(int)

  • read

    public int read() throws IOException

    Read a single character. Line terminators are compressed into single newline ('\n') characters. The current line number is incremented whenever a line terminator is read, or when the end of the stream is reached and the last character in the stream is not a line terminator.

    Overrides: read in class BufferedReader 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. This method will block until some input is available, an I/O error occurs, or the end of the stream is reached.

    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.

    Line terminators are compressed into single newline ('\n') characters. The current line number is incremented whenever a line terminator is read, or when the end of the stream is reached and the last character in the stream is not a line terminator.

    Overrides: read in class BufferedReader 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

    Read a line of text. Line terminators are compressed into single newline ('\n') characters. The current line number is incremented whenever a line terminator is read, or when the end of the stream is reached and the last character in the stream is not a line terminator.

    Overrides: readLine in class BufferedReader 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 Throws: IOException - If an I/O error occurs See Also:

    • Files.readAllLines(Path, Charset)

  • mark

    public void mark(int readAheadLimit) throws IOException

    Mark the present position in the stream. Subsequent calls to reset() will attempt to reposition the stream to this point, and will also reset the line number appropriately.

    Overrides: mark in class BufferedReader Parameters: readAheadLimit - Limit on the number of characters that may be read while still preserving the mark. After reading this many characters, attempting to reset the stream may fail. Throws: IOException - If an I/O error occurs

  • reset

    public void reset() throws IOException

    Reset the stream to the most recent mark.

    Overrides: reset in class BufferedReader Throws: IOException - If the stream has not been marked, or if the mark has been invalidated

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