Class ChecksumInputStream.Builder

java.lang.Object

org.apache.commons.io.build.AbstractSupplier<ChecksumInputStream, ChecksumInputStream.Builder>

org.apache.commons.io.build.AbstractOriginSupplier<ChecksumInputStream, ChecksumInputStream.Builder>

org.apache.commons.io.build.AbstractStreamBuilder<ChecksumInputStream, ChecksumInputStream.Builder>

org.apache.commons.io.input.ProxyInputStream.AbstractBuilder<ChecksumInputStream, ChecksumInputStream.Builder>

org.apache.commons.io.input.ChecksumInputStream.Builder

All Implemented Interfaces:

IOSupplier<ChecksumInputStream>

Enclosing class:

ChecksumInputStream

public static class ChecksumInputStream.Builder
extends ProxyInputStream.AbstractBuilder<ChecksumInputStream, ChecksumInputStream.Builder>

Builds a new ChecksumInputStream.

There is no default Checksum; you MUST provide one. This avoids any issue with a default Checksum being proven deficient or insecure in the future.

Using NIO

ChecksumInputStream s = ChecksumInputStream.builder()
  .setPath(Paths.get("MyFile.xml"))
  .setChecksum(new CRC32())
  .setExpectedChecksumValue(12345)
  .get();

Using IO

ChecksumInputStream s = ChecksumInputStream.builder()
  .setFile(new File("MyFile.xml"))
  .setChecksum(new CRC32())
  .setExpectedChecksumValue(12345)
  .get();

Validating only part of an InputStream

The following validates the first 100 bytes of the given input.

ChecksumInputStream s = ChecksumInputStream.builder()
  .setPath(Paths.get("MyFile.xml"))
  .setChecksum(new CRC32())
  .setExpectedChecksumValue(12345)
  .setCountThreshold(100)
  .get();

To validate input after the beginning of a stream, build an instance with an InputStream starting where you want to validate.

InputStream inputStream = ...;
inputStream.read(...);
inputStream.skip(...);
ChecksumInputStream s = ChecksumInputStream.builder()
  .setInputStream(inputStream)
  .setChecksum(new CRC32())
  .setExpectedChecksumValue(12345)
  .setCountThreshold(100)
  .get();

Since:

2.16.0

See Also:

• get()

Constructor Summary

Constructors

Constructor	Description
Builder()	Constructs a new builder of ChecksumInputStream.

Method Summary

Modifier and Type	Method	Description
ChecksumInputStream	get()	Builds a new ChecksumInputStream.
ChecksumInputStream.Builder	setChecksum(Checksum checksum)	Sets the Checksum.
ChecksumInputStream.Builder	setCountThreshold(long countThreshold)	Sets the count threshold to limit how much input is consumed to update the Checksum before the input stream validates its value.
ChecksumInputStream.Builder	setExpectedChecksumValue(long expectedChecksumValue)	The expected Checksum value once the stream is exhausted or the count threshold is reached.

Methods inherited from class ProxyInputStream.AbstractBuilder

getAfterRead, setAfterRead

Methods inherited from class AbstractStreamBuilder

getBufferSize, getBufferSizeDefault, getChannel, getCharSequence, getCharset, getCharsetDefault, getFile, getInputStream, getOpenOptions, getOutputStream, getPath, getRandomAccessFile, getReader, getWriter, setBufferSize, setBufferSize, setBufferSizeChecker, setBufferSizeDefault, setBufferSizeMax, setCharset, setCharset, setCharsetDefault, setOpenOptions

Methods inherited from class AbstractOriginSupplier

checkOrigin, getOrigin, hasOrigin, newByteArrayOrigin, newChannelOrigin, newCharSequenceOrigin, newFileOrigin, newFileOrigin, newInputStreamOrigin, newOutputStreamOrigin, newPathOrigin, newPathOrigin, newRandomAccessFileOrigin, newRandomAccessFileOrigin, newReaderOrigin, newURIOrigin, newWriterOrigin, setByteArray, setChannel, setCharSequence, setFile, setFile, setInputStream, setOrigin, setOutputStream, setPath, setPath, setRandomAccessFile, setRandomAccessFile, setReader, setURI, setWriter

Methods inherited from class AbstractSupplier

asThis

Methods inherited from class Object

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

Methods inherited from interface IOSupplier

asSupplier, getUnchecked

Constructor Details

Builder

public Builder()

Constructs a new builder of ChecksumInputStream.

Method Details

get

public ChecksumInputStream get()
                        throws IOException

Builds a new ChecksumInputStream.

You must set an aspect that supports AbstractStreamBuilder.getInputStream(), otherwise, this method throws an exception.

This builder uses the following aspects:

• AbstractStreamBuilder.getInputStream() gets the target aspect.
• Checksum
• expectedChecksumValue
• countThreshold

Returns:

a new instance.

Throws:

IllegalStateException - if the origin is null.

UnsupportedOperationException - if the origin cannot be converted to an InputStream.

IOException - if an I/O error occurs converting to an InputStream using AbstractStreamBuilder.getInputStream().

See Also:

• AbstractStreamBuilder.getInputStream()
• IOSupplier.getUnchecked()

setChecksum

public ChecksumInputStream.Builder setChecksum(Checksum checksum)

Sets the Checksum. There is no default Checksum, you MUST provide one. This avoids any issue with a default Checksum being proven deficient or insecure in the future.

Parameters:

checksum - the Checksum.

Returns:

this instance.

setCountThreshold

public ChecksumInputStream.Builder setCountThreshold(long countThreshold)

Sets the count threshold to limit how much input is consumed to update the Checksum before the input stream validates its value.

By default, all input updates the Checksum.

Parameters:

countThreshold - the count threshold. A negative number means the threshold is unbound.

Returns:

this instance.

setExpectedChecksumValue

public ChecksumInputStream.Builder setExpectedChecksumValue(long expectedChecksumValue)

The expected Checksum value once the stream is exhausted or the count threshold is reached.

Parameters:

expectedChecksumValue - The expected Checksum value.

Returns:

this instance.