Class FileWriter

java.lang.Object
java.io.Writer
java.io.OutputStreamWriter
java.io.FileWriter
All Implemented Interfaces:
Closeable, Flushable, Appendable, AutoCloseable
public class FileWriter extends OutputStreamWriter
Writes text to character files using a default buffer size. Encoding from characters to bytes uses either a specified charset or the default charset.

Whether or not a file is available or may be created depends upon the underlying platform. Some platforms, in particular, allow a file to be opened for writing by only one FileWriter (or other file-writing object) at a time. In such situations the constructors in this class will fail if the file involved is already open.

The FileWriter is meant for writing streams of characters. For writing streams of raw bytes, consider using a FileOutputStream.

Since:
1.1
See Also:

  • Field Summary

    Fields declared in class Writer

    lock
    Modifier and Type
    Field
    Description
    protected Object
    lock
    The object used to synchronize operations on this stream.

  • Constructor Summary

    Constructors
    Constructor
    Description
    FileWriter(File file)
    Constructs a FileWriter given the File to write, using the default charset
    FileWriter(FileDescriptor fd)
    Constructs a FileWriter given a file descriptor, using the default charset.
    FileWriter(File file, boolean append)
    Constructs a FileWriter given the File to write and a boolean indicating whether to append the data written, using the default charset.
    FileWriter(File file, Charset charset)
    Constructs a FileWriter given the File to write and charset.
    FileWriter(File file, Charset charset, boolean append)
    Constructs a FileWriter given the File to write, charset and a boolean indicating whether to append the data written.
    FileWriter(String fileName)
    Constructs a FileWriter given a file name, using the default charset
    FileWriter(String fileName, boolean append)
    Constructs a FileWriter given a file name and a boolean indicating whether to append the data written, using the default charset.
    FileWriter(String fileName, Charset charset)
    Constructs a FileWriter given a file name and charset.
    FileWriter(String fileName, Charset charset, boolean append)
    Constructs a FileWriter given a file name, charset and a boolean indicating whether to append the data written.

  • Method Summary

    Methods declared in class OutputStreamWriter

    close, flush, getEncoding, write, write, write
    Modifier and Type
    Method
    Description
    void
    close()
    Closes the stream, flushing it first.
    void
    flush()
    Flushes the stream.
    String
    getEncoding()
    Returns the name of the character encoding being used by this stream.
    void
    write(char[] cbuf, int off, int len)
    Writes a portion of an array of characters.
    void
    write(int c)
    Writes a single character.
    void
    write(String str, int off, int len)
    Writes a portion of a string.

    Methods declared in class Writer

    append, append, append, nullWriter, write, write
    Modifier and Type
    Method
    Description
    Writer
    append(char c)
    Appends the specified character to this writer.
    Writer
    append(CharSequence csq)
    Appends the specified character sequence to this writer.
    Writer
    append(CharSequence csq, int start, int end)
    Appends a subsequence of the specified character sequence to this writer.
    static Writer
    nullWriter()
    Returns a new Writer which discards all characters.
    void
    write(char[] cbuf)
    Writes an array of characters.
    void
    write(String str)
    Writes a string.

    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

    • FileWriter

      public FileWriter(String fileName) throws IOException
      Constructs a FileWriter given a file name, using the default charset
      Parameters:
      fileName - String The system-dependent filename.
      Throws:
      IOException - if the named file exists but is a directory rather than a regular file, does not exist but cannot be created, or cannot be opened for any other reason
      See Also:

    • FileWriter

      public FileWriter(String fileName, boolean append) throws IOException
      Constructs a FileWriter given a file name and a boolean indicating whether to append the data written, using the default charset.
      Parameters:
      fileName - String The system-dependent filename.
      append - boolean if true, then data will be written to the end of the file rather than the beginning.
      Throws:
      IOException - if the named file exists but is a directory rather than a regular file, does not exist but cannot be created, or cannot be opened for any other reason
      See Also:

    • FileWriter

      public FileWriter(File file) throws IOException
      Constructs a FileWriter given the File to write, using the default charset
      Parameters:
      file - the File to write.
      Throws:
      IOException - if the file exists but is a directory rather than a regular file, does not exist but cannot be created, or cannot be opened for any other reason
      See Also:

    • FileWriter

      public FileWriter(File file, boolean append) throws IOException
      Constructs a FileWriter given the File to write and a boolean indicating whether to append the data written, using the default charset.
      Parameters:
      file - the File to write
      append - if true, then bytes will be written to the end of the file rather than the beginning
      Throws:
      IOException - if the file exists but is a directory rather than a regular file, does not exist but cannot be created, or cannot be opened for any other reason
      Since:
      1.4
      See Also:

    • FileWriter

      public FileWriter(FileDescriptor fd)
      Constructs a FileWriter given a file descriptor, using the default charset.
      Parameters:
      fd - the FileDescriptor to write.
      See Also:

    • FileWriter

      public FileWriter(String fileName, Charset charset) throws IOException
      Constructs a FileWriter given a file name and charset.
      Parameters:
      fileName - the name of the file to write
      charset - the charset
      Throws:
      IOException - if the named file exists but is a directory rather than a regular file, does not exist but cannot be created, or cannot be opened for any other reason
      Since:
      11

    • FileWriter

      public FileWriter(String fileName, Charset charset, boolean append) throws IOException
      Constructs a FileWriter given a file name, charset and a boolean indicating whether to append the data written.
      Parameters:
      fileName - the name of the file to write
      charset - the charset
      append - a boolean. If true, the writer will write the data to the end of the file rather than the beginning.
      Throws:
      IOException - if the named file exists but is a directory rather than a regular file, does not exist but cannot be created, or cannot be opened for any other reason
      Since:
      11

    • FileWriter

      public FileWriter(File file, Charset charset) throws IOException
      Constructs a FileWriter given the File to write and charset.
      Parameters:
      file - the File to write
      charset - the charset
      Throws:
      IOException - if the file exists but is a directory rather than a regular file, does not exist but cannot be created, or cannot be opened for any other reason
      Since:
      11

    • FileWriter

      public FileWriter(File file, Charset charset, boolean append) throws IOException
      Constructs a FileWriter given the File to write, charset and a boolean indicating whether to append the data written.
      Parameters:
      file - the File to write
      charset - the charset
      append - a boolean. If true, the writer will write the data to the end of the file rather than the beginning.
      Throws:
      IOException - if the file exists but is a directory rather than a regular file, does not exist but cannot be created, or cannot be opened for any other reason
      Since:
      11