de.caff.io

Class InputStreamLineBuffer

java.lang.Object

de.caff.io.InputStreamLineBuffer

All Implemented Interfaces:

java.lang.Runnable

public class InputStreamLineBuffer
extends java.lang.Object
implements java.lang.Runnable

A sink for data from an input stream which collects the incoming data as text lines.

It is especially useful for handling the outputting streams of Process. Create via startOn(InputStream) or startOn(InputStream, int) which will automatically collect all bytes from the stream in a background thread.

See InputStreamBuffer if you are interested in the raw bytes, InputStreamSink if you are not interested at all in the content of the streams, and InputStreamPipe which forwards all bytes from one stream to another.

Since:

August 10, 2022

Author:

Rammi

Field Summary

Fields

Modifier and Type	Field and Description
static int	DEFAULT_BUFFER_SIZE Default size for line buffers.
static int	MAXIMUM_ARRAY_SIZE This is suggestion from OpenJDK's ArraySupport class which makes sure to work with all Java versions.

Constructor Summary

Constructors

Constructor and Description
InputStreamLineBuffer(java.io.InputStream is, int maxSize) Constructor using the system's default charset.
InputStreamLineBuffer(java.io.InputStream is, int maxSize, java.nio.charset.Charset charset) Constructor.

Method Summary

Modifier and Type	Method and Description
void	clearOutput() Clear the output.
java.io.IOException	getError() Return a possible error which happened during reading the stream when using the run() method.
java.lang.String[]	getLines() Get the collected output lines.
java.lang.String	getOutput() Get the output as text, using the default charset.
long	getTotalByteCount() Get the total number of bytes read by this sink.
void	run() When an object implementing interface Runnable is used to create a thread, starting the thread causes the object's run method to be called in that separately executing thread.
static InputStreamLineBuffer	startOn(java.io.InputStream inStream) Start a sink on the given stream.
static InputStreamLineBuffer	startOn(java.io.InputStream inStream, int bufferSize) Start a sink on the given stream.
Indexable<java.lang.String>	toLineIndexable() Get the buffered lines as an independent indexable.
java.util.List<java.lang.String>	toLineList() Get the buffered lines as an independent indexable.
java.lang.String	toString()
Indexable<java.lang.String>	viewLines() Get a view to the buffered lines.

Methods inherited from class java.lang.Object

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

Field Detail

MAXIMUM_ARRAY_SIZE

public static final int MAXIMUM_ARRAY_SIZE

This is suggestion from OpenJDK's ArraySupport class which makes sure to work with all Java versions.

See Also:

Constant Field Values

DEFAULT_BUFFER_SIZE

public static final int DEFAULT_BUFFER_SIZE

Default size for line buffers.

See Also:

Constant Field Values

Constructor Detail

InputStreamLineBuffer

public InputStreamLineBuffer(@NotNull
                             java.io.InputStream is,
                             int maxSize)

Constructor using the system's default charset.

Note that in most use cases the factory methods startOn(InputStream) and startOn(InputStream, int) are better ways to create an input stream sink.

Parameters:

is - input stream

maxSize - maximum number of buffered lines, implementation might store one line more

InputStreamLineBuffer

public InputStreamLineBuffer(@NotNull
                             java.io.InputStream is,
                             int maxSize,
                             @NotNull
                             java.nio.charset.Charset charset)

Constructor.

Note that in most use cases the factory methods startOn(InputStream) and startOn(InputStream, int) are better ways to create an input stream sink.

Parameters:

is - input stream

maxSize - maximum number of buffered lines, implementation might store one line more

charset - charset used to decode the input stream

Method Detail

getError

@Nullable
public java.io.IOException getError()

Return a possible error which happened during reading the stream when using the run() method.

Returns:

error caught during run() or null, if no error was caught

viewLines

@NotNull
public Indexable<java.lang.String> viewLines()

Get a view to the buffered lines. Note that this does not copy the lines, but has the disadvantage that the view will become invalid as soon as more data is written to this buffer. If the input is not close prefer toLineIndexable(), toLineList(), or getLines().

Returns:

lines

See Also:

toLineIndexable(), toLineList(), getLines()

toLineIndexable

@NotNull
public Indexable<java.lang.String> toLineIndexable()

Get the buffered lines as an independent indexable.

Returns:

buffered lines

See Also:

viewLines(), toLineList(), getLines()

toLineList

@NotNull
public java.util.List<java.lang.String> toLineList()

Get the buffered lines as an independent indexable.

Returns:

buffered lines

See Also:

viewLines(), toLineIndexable(), getLines()

getLines

@NotNull
public java.lang.String[] getLines()

Get the collected output lines.

Returns:

byte array with the collected bytes

See Also:

viewLines(), toLineIndexable(), toLineList()

getOutput

@NotNull
public java.lang.String getOutput()

Get the output as text, using the default charset. Note that due to limited buffer size for multi-byte encodings such as UTF-8 the first characters may be broken.

Returns:

stream output as text

clearOutput

public void clearOutput()

Clear the output. This will remove all cached bytes from the buffer.

getTotalByteCount

public long getTotalByteCount()

Get the total number of bytes read by this sink.

Returns:

total number of bytes read so far

run

public void run()

When an object implementing interface Runnable is used to create a thread, starting the thread causes the object's run method to be called in that separately executing thread.

The general contract of the method run is that it may take any action whatsoever.

Specified by:

run in interface java.lang.Runnable

See Also:

Thread.run()

startOn

@NotNull
public static InputStreamLineBuffer startOn(@NotNull
                                                     java.io.InputStream inStream)

Start a sink on the given stream. This method uses DEFAULT_BUFFER_SIZE as buffer size.

Parameters:

inStream - input stream

Returns:

input stream line buffer based on the given stream

See Also:

startOn(InputStream, int)

startOn

@NotNull
public static InputStreamLineBuffer startOn(@NotNull
                                                     java.io.InputStream inStream,
                                                     int bufferSize)

Start a sink on the given stream.

Parameters:

inStream - input stream

bufferSize - maximum number of cached lines

Returns:

input stream line buffer based on the given stream

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object