Class FileReader

java.lang.Object
java.io.Reader
java.io.InputStreamReader
java.io.FileReader
All Implemented Interfaces:
Closeable, AutoCloseable, Readable
public class FileReader extends InputStreamReader
Reads text from character files using a default buffer size. Decoding from bytes to characters uses either a specified charset or the default charset.

The FileReader is meant for reading streams of characters. For reading streams of raw bytes, consider using a FileInputStream.

Since:
1.1
See Also:

  • 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
    FileReader(File file)
    Creates a new FileReader, given the File to read, using the default charset.
    FileReader(FileDescriptor fd)
    Creates a new FileReader, given the FileDescriptor to read, using the default charset.
    FileReader(File file, Charset charset)
    Creates a new FileReader, given the File to read and the charset.
    FileReader(String fileName)
    Creates a new FileReader, given the name of the file to read, using the default charset.
    FileReader(String fileName, Charset charset)
    Creates a new FileReader, given the name of the file to read and the charset.

  • Method Summary

    Methods declared in class InputStreamReader

    close, getEncoding, read, read, ready
    Modifier and Type
    Method
    Description
    void
    close()
    Closes the stream and releases any system resources associated with it.
    String
    getEncoding()
    Returns the name of the character encoding being used by this stream.
    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.

    Methods declared in class Reader

    mark, markSupported, nullReader, of, read, read, readAllAsString, readAllLines, reset, skip, transferTo
    Modifier and Type
    Method
    Description
    void
    mark(int readAheadLimit)
    Marks the present position in the stream.
    boolean
    markSupported()
    Tells whether this stream supports the mark() operation.
    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.
    void
    reset()
    Resets the stream.
    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()
    Answers a new instance of the same class as the receiver, whose slots have been filled in with the values in the slots of the receiver.
    boolean
    equals(Object o)
    Compares the argument to the receiver, and answers true if they represent the same object using a class specific comparison.
    protected void
    finalize()
    Deprecated, for removal: This API element is subject to removal in a future version.
    May cause performance issues, deadlocks and hangs.
    final Class<? extends Object>
    getClass()
    Answers the unique instance of java.lang.Class which represents the class of the receiver.
    int
    hashCode()
    Answers an integer hash code for the receiver.
    final void
    notify()
    Causes one thread which is waiting on the receiver to be made ready to run.
    final void
    notifyAll()
    Causes all threads which are waiting on the receiver to be made ready to run.
    String
    toString()
    Answers a string containing a concise, human-readable description of the receiver.
    final void
    wait()
    Causes the thread which sent this message to be made not ready to run pending some change in the receiver (as indicated by notify or notifyAll).
    final void
    wait(long time)
    Causes the thread which sent this message to be made not ready to run either pending some change in the receiver (as indicated by notify or notifyAll) or the expiration of the timeout.
    final void
    wait(long time, int frac)
    Causes the thread which sent this message to be made not ready to run either pending some change in the receiver (as indicated by notify or notifyAll) or the expiration of the timeout.

  • Constructor Details

    • FileReader

      public FileReader(String fileName) throws FileNotFoundException
      Creates a new FileReader, given the name of the file to read, using the default charset.
      Parameters:
      fileName - the name of the file to read
      Throws:
      FileNotFoundException - if the named file does not exist, is a directory rather than a regular file, or for some other reason cannot be opened for reading.
      See Also:

    • FileReader

      public FileReader(File file) throws FileNotFoundException
      Creates a new FileReader, given the File to read, using the default charset.
      Parameters:
      file - the File to read
      Throws:
      FileNotFoundException - if the file does not exist, is a directory rather than a regular file, or for some other reason cannot be opened for reading.
      See Also:

    • FileReader

      public FileReader(FileDescriptor fd)
      Creates a new FileReader, given the FileDescriptor to read, using the default charset.
      Parameters:
      fd - the FileDescriptor to read
      See Also:

    • FileReader

      public FileReader(String fileName, Charset charset) throws IOException
      Creates a new FileReader, given the name of the file to read and the charset.
      Parameters:
      fileName - the name of the file to read
      charset - the charset
      Throws:
      IOException - if the named file does not exist, is a directory rather than a regular file, or for some other reason cannot be opened for reading.
      Since:
      11

    • FileReader

      public FileReader(File file, Charset charset) throws IOException
      Creates a new FileReader, given the File to read and the charset.
      Parameters:
      file - the File to read
      charset - the charset
      Throws:
      IOException - if the file does not exist, is a directory rather than a regular file, or for some other reason cannot be opened for reading.
      Since:
      11