org.apache.commons.io.input

Class ChecksumInputStream.Builder

java.lang.Object

org.apache.commons.io.build.AbstractSupplier<T,B>

org.apache.commons.io.build.AbstractOriginSupplier<T,B>

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

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

All Implemented Interfaces:

IOSupplier<ChecksumInputStream>

Enclosing class:

ChecksumInputStream

public static class ChecksumInputStream.Builder
extends AbstractStreamBuilder<ChecksumInputStream,ChecksumInputStream.Builder>

Builds a new ChecksumInputStream.

There is no default Checksum; you MUST provide one.

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();
 

See Also:

get()

Field Summary

Fields

Modifier and Type	Field and Description
private java.util.zip.Checksum	checksum There is no default checksum, you MUST provide one.
private long	countThreshold The count threshold to limit how much input is consumed to update the Checksum before the input stream validates its value.
private long	expectedChecksumValue The expected Checksum value once the stream is exhausted or the count threshold is reached.

Constructor Summary

Constructors

Constructor and Description
Builder()

Method Summary

Modifier and Type	Method and Description
ChecksumInputStream	get() Builds a new ChecksumInputStream.
ChecksumInputStream.Builder	setChecksum(java.util.zip.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 org.apache.commons.io.build.AbstractStreamBuilder

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

Methods inherited from class org.apache.commons.io.build.AbstractOriginSupplier

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

Methods inherited from class org.apache.commons.io.build.AbstractSupplier

asThis

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.commons.io.function.IOSupplier

asSupplier

Field Detail

checksum

private java.util.zip.Checksum 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.

countThreshold

private long countThreshold

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.

expectedChecksumValue

private long expectedChecksumValue

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

Constructor Detail

Builder

public Builder()

Method Detail

get

public ChecksumInputStream get()
                        throws java.io.IOException

Builds a new ChecksumInputStream.

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

This builder use the following aspects:

• AbstractStreamBuilder.getInputStream()
• Checksum
• expectedChecksumValue
• countThreshold

Returns:

a new instance.

Throws:

java.lang.IllegalStateException - if the origin is null.

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

java.io.IOException - if an I/O error occurs.

See Also:

AbstractStreamBuilder.getInputStream()

setChecksum

public ChecksumInputStream.Builder setChecksum(java.util.zip.Checksum checksum)

Sets the Checksum.

Parameters:

checksum - the Checksum.

Returns:

this.

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.

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.