Package no.digipost.io

Class LimitedInputStream

java.lang.Object

java.io.InputStream

java.io.FilterInputStream

no.digipost.io.LimitedInputStream

All Implemented Interfaces:

Closeable, AutoCloseable

public final class LimitedInputStream
extends FilterInputStream
implements Closeable

An InputStream which limits how many bytes which can be read.

This class is based on the LimitedInputStream from Apache Commons Fileupload (v1.3.2), which has the license as the Digg library, Apache License 2.0, but also supports to silently treat the limit as EOF without any signal to distinguish between the EOF of the wrapped stream and the limited stream.

Field Summary

Fields

Modifier and Type	Field	Description
static Supplier<Exception>	SILENTLY_EOF_ON_REACHING_LIMIT	Supply this instead of an exception supplier as parameter when contructing a new LimitedInputStream to instruct it to treat the limit as an ordinary EOF, and not throw any exception to signal that the limit was reached during consumption of the stream.

Fields inherited from class java.io.FilterInputStream

in

Constructor Summary

Constructors

Constructor	Description
LimitedInputStream(InputStream inputStream, DataSize maxDataToRead, Supplier<? extends Exception> throwIfTooManyBytes)

Method Summary

Modifier and Type	Method	Description
int	read()	Reads the next byte of data from this input stream.
int	read(byte[] b, int off, int len)	Reads up to len bytes of data from this input stream into an array of bytes.

Methods inherited from class java.io.FilterInputStream

available, close, mark, markSupported, read, reset, skip

Methods inherited from class java.io.InputStream

nullInputStream, readAllBytes, readNBytes, readNBytes, transferTo

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.io.Closeable

close

Field Detail

SILENTLY_EOF_ON_REACHING_LIMIT

public static final Supplier<Exception> SILENTLY_EOF_ON_REACHING_LIMIT

Supply this instead of an exception supplier as parameter when contructing a new LimitedInputStream to instruct it to treat the limit as an ordinary EOF, and not throw any exception to signal that the limit was reached during consumption of the stream.

Invoking get() on this will throw an exception.

Constructor Detail

LimitedInputStream

public LimitedInputStream(InputStream inputStream,
                          DataSize maxDataToRead,
                          Supplier<? extends Exception> throwIfTooManyBytes)

See Also:

DiggIO.limit(InputStream, DataSize, Supplier)

Method Detail

read

public int read()
         throws IOException

Reads the next byte of data from this input stream. The value byte is returned as an int in the range 0 to 255. If no byte is available because the end of the stream has been reached, the value -1 is returned. This method blocks until input data is available, the end of the stream is detected, or an exception is thrown.

This method simply performs in.read() and returns the result.

Overrides:

read in class FilterInputStream

Returns:

the next byte of data, or -1 if the end of the stream is reached.

Throws:

IOException - if an I/O error occurs.

See Also:

FilterInputStream.in

read

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

Reads up to len bytes of data from this input stream into an array of bytes. If len is not zero, the method blocks until some input is available; otherwise, no bytes are read and 0 is returned.

This method simply performs in.read(b, off, len) and returns the result.

Overrides:

read in class FilterInputStream

Parameters:

b - the buffer into which the data is read.

off - The start offset in the destination array b.

len - the maximum number of bytes read.

Returns:

the total number of bytes read into the buffer, or -1 if there is no more data because the end of the stream has been reached.

Throws:

NullPointerException - If b is null.

IndexOutOfBoundsException - If off is negative, len is negative, or len is greater than b.length - off

IOException - if an I/O error occurs.

See Also:

FilterInputStream.in