Packages 
Package Description
org.apache.commons.io
This package defines utility classes for working with streams, readers, writers and files.
org.apache.commons.io.comparator
This package provides various Comparator implementations for Files.
org.apache.commons.io.file
This package provides extensions in the realm of java.nio.file.
org.apache.commons.io.file.spi
This package provides extensions in the realm of java.nio.file.spi.
org.apache.commons.io.filefilter
This package defines an interface (IOFileFilter) that combines both FileFilter and FilenameFilter.
org.apache.commons.io.function
This package defines IO-only related functional interfaces for lambda expressions and method references.
org.apache.commons.io.input
This package provides implementations of input classes, such as InputStream and Reader.
org.apache.commons.io.input.buffer
This package provides implementations of buffered input classes, such as CircularBufferInputStream and PeekableInputStream.
org.apache.commons.io.monitor
This package provides a component for monitoring file system events (directory and file create, update and delete events).
org.apache.commons.io.output
This package provides implementations of output classes, such as OutputStream and Writer.
org.apache.commons.io.serialization
This package provides a framework for controlling the deserialization of classes.