Class FileWriter

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

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

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