Package io.undertow.servlet.spec

Class ServletOutputStreamImpl

java.lang.Object

java.io.OutputStream

jakarta.servlet.ServletOutputStream

io.undertow.servlet.spec.ServletOutputStreamImpl

All Implemented Interfaces:

BufferWritableOutputStream, Closeable, Flushable, AutoCloseable

public class ServletOutputStreamImpl
extends ServletOutputStream
implements BufferWritableOutputStream

This stream essentially has two modes. When it is being used in standard blocking mode then it will buffer in the pooled buffer. If the stream is closed before the buffer is full it will set a content-length header if one has not been explicitly set.

If a content-length header was present when the stream was created then it will automatically close and flush itself once the appropriate amount of data has been written.

Once the listener has been set it goes into async mode, and writes become non blocking. Most methods have two different code paths, based on if the listener has been set or not

Once the write listener has been set operations must only be invoked on this stream from the write listener callback. Attempting to invoke from a different thread will result in an IllegalStateException.

Async listener tasks are queued in the AsyncContextImpl. At most one listener can be active at one time, which simplifies the thread safety requirements.

Author:

Stuart Douglas

Constructor Summary

Constructors

Constructor	Description
ServletOutputStreamImpl(ServletRequestContext servletRequestContext)	Construct a new instance.
ServletOutputStreamImpl(ServletRequestContext servletRequestContext, int bufferSize)	Construct a new instance.

Method Summary

Modifier and Type	Method	Description
void	close()
void	closeAsync()	Closes the channel, and flushes any data out using async IO
void	flush()
void	flushInternal()
boolean	isClosed()
boolean	isReady()	Returns true if data can be written without blocking else returns false.
void	resetBuffer()
void	setBufferSize(int size)
void	setWriteListener(WriteListener writeListener)	Instructs the ServletOutputStream to invoke the provided WriteListener when it is possible to write
void	transferFrom(FileChannel source)
void	write(byte[] b)
void	write(byte[] b, int off, int len)
void	write(int b)
void	write(ByteBuffer byteBuffer)
void	write(ByteBuffer[] buffers)

Methods inherited from class jakarta.servlet.ServletOutputStream

print, print, print, print, print, print, print, println, println, println, println, println, println, println, println

Methods inherited from class java.io.OutputStream

nullOutputStream

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

ServletOutputStreamImpl

public ServletOutputStreamImpl(ServletRequestContext servletRequestContext)

Construct a new instance. No write timeout is configured.

ServletOutputStreamImpl

public ServletOutputStreamImpl(ServletRequestContext servletRequestContext,
 int bufferSize)

Construct a new instance. No write timeout is configured.

Method Details

write

public void write(int b)
           throws IOException

Specified by:

write in class OutputStream

Throws:

IOException

write

public void write(byte[] b)
           throws IOException

Overrides:

write in class OutputStream

Throws:

IOException

write

public void write(byte[] b,
 int off,
 int len)
           throws IOException

Overrides:

write in class OutputStream

Throws:

IOException

write

public void write(ByteBuffer[] buffers)
           throws IOException

Specified by:

write in interface BufferWritableOutputStream

Throws:

IOException

write

public void write(ByteBuffer byteBuffer)
           throws IOException

Specified by:

write in interface BufferWritableOutputStream

Throws:

IOException

flush

public void flush()
           throws IOException

Specified by:

flush in interface Flushable

Overrides:

flush in class OutputStream

Throws:

IOException

flushInternal

public void flushInternal()
                   throws IOException

Throws:

IOException

transferFrom

public void transferFrom(FileChannel source)
                  throws IOException

Specified by:

transferFrom in interface BufferWritableOutputStream

Throws:

IOException

close

public void close()
           throws IOException

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

Overrides:

close in class OutputStream

Throws:

IOException

closeAsync

public void closeAsync()
                throws IOException

Closes the channel, and flushes any data out using async IO

This is used in two situations, if an output stream is not closed when a request is done, and when performing a close on a stream that is in async mode

Throws:

IOException

resetBuffer

public void resetBuffer()

setBufferSize

public void setBufferSize(int size)

isClosed

public boolean isClosed()

isReady

public boolean isReady()

Description copied from class: ServletOutputStream

Returns true if data can be written without blocking else returns false.

If this method returns false and a WriteListener has been set with ServletOutputStream.setWriteListener(WriteListener), then container will subsequently invoke WriteListener.onWritePossible() once a write operation becomes possible without blocking. Other than the initial call, WriteListener.onWritePossible() will only be called if and only if this method is called and returns false.

Specified by:

isReady in class ServletOutputStream

Returns:

true if data can be written without blocking, otherwise returns false.

See Also:

• WriteListener

setWriteListener

public void setWriteListener(WriteListener writeListener)

Description copied from class: ServletOutputStream

Instructs the ServletOutputStream to invoke the provided WriteListener when it is possible to write

Specified by:

setWriteListener in class ServletOutputStream

Parameters:

writeListener - the WriteListener that should be notified when it's possible to write