Class FilterWriter

java.lang.Object

java.io.Writer

java.io.FilterWriter

All Implemented Interfaces:: Closeable, Flushable, Appendable, AutoCloseable

public abstract class FilterWriter extends Writer

Abstract class for writing filtered character streams. The abstract class FilterWriter itself provides default methods that pass all requests to the contained stream. Subclasses of FilterWriter should override some of these methods and may also provide additional methods and fields.

Since:: 1.1

Field Summary

Modifier and Type	Field	Description
`protected Writer`	`out`	The underlying character-output stream.

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

FilterWriter(Writer out)

Modifier	Constructor	Description
`protected`	Create a new filtered writer.

Method Summary

Modifier and Type	Method	Description
`void`	`close()`	Closes the stream, flushing it first.
`void`	`flush()`	Flushes the 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.

Field Details

out

protected Writer out

The underlying character-output stream.

Constructor Details

FilterWriter

protected FilterWriter(Writer out)

Create a new filtered writer.

Parameters:: out - a Writer object to provide the underlying stream.
Throws:: NullPointerException - if out is null

Method Details

write

public void write(int c) throws IOException

Writes a single character.

Overrides:: write in class Writer
Parameters:: c - int specifying a character to be written
Throws:: IOException - If an I/O error occurs

write

public void write(char[] cbuf, int off, int len) throws IOException

Writes a portion of an array of characters.

Specified by:: write in class Writer
Parameters:: cbuf - Buffer of characters to be written; off - Offset from which to start reading characters; len - Number of characters to be written
Throws:: IndexOutOfBoundsException - If the values of the off and len parameters cause the corresponding method of the underlying Writer to throw an IndexOutOfBoundsException; IOException - If an I/O error occurs

write

public void write(String str, int off, int len) throws IOException

Writes a portion of a string.

Overrides:: write in class Writer
Parameters:: str - String to be written; off - Offset from which to start reading characters; len - Number of characters to be written
Throws:: IndexOutOfBoundsException - If the values of the off and len parameters cause the corresponding method of the underlying Writer to throw an IndexOutOfBoundsException; IOException - If an I/O error occurs

flush

public void flush() throws IOException

Flushes the stream.

Specified by:: flush in interface Flushable
Specified by:: flush in class Writer
Throws:: IOException - If an I/O error occurs

close

public void close() throws IOException

Description copied from class: Writer

Closes the stream, flushing it first. Once the stream has been closed, further write() or flush() invocations will cause an IOException to be thrown. 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 Writer
Throws:: IOException - If an I/O error occurs

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