Package org.apache.hadoop.io
package org.apache.hadoop.io
Generic i/o code for use when reading and writing data to the network,
to databases, and to files.
-
ClassDescriptionAbstract base class for MapWritable and SortedMapWritable Unlike org.apache.nutch.crawl.MapWritable, this class allows creation of MapWritable<Writable, MapWritable> so the CLASS_TO_ID and ID_TO_CLASS maps travel with the class instead of being static.A dense file-based mapping from integers to values.Provide access to an existing array file.Write a new array file.This is a wrapper class.A Writable for arrays containing instances of a class.Interface supported by
WritableComparabletypes supporting ordering/permutation by a representative set of bytes.This class extendsMapFileand provides very much the same functionality.A WritableComparable for booleans.A Comparator optimized for BooleanWritable.A byte array backed output stream with a limit.A byte sequence that is usable as a key or value.A Comparator optimized for BytesWritable.A WritableComparable for a single byte.A Comparator optimized for ByteWritable.Deprecated.use java.io.CloseableA base-class for Writables which store themselves compressed and lazily inflate on field access.A reusableDataInputimplementation that reads from an in-memory buffer.A reusableDataOutputimplementation that writes to an in-memory buffer.OutputStream implementation that wraps a DataOutput.DefaultStringifier is the default implementation of theStringifierinterface which stringifies the objects using base64 encoding of the serialized version of the objects.Writable for Double values.A Comparator optimized for DoubleWritable.This is a simple ByteBufferPool which just creates ByteBuffers as needed.EnumSetWritable<E extends Enum<E>>A Writable wrapper for EnumSet.A WritableComparable for floats.A Comparator optimized for FloatWritable.A wrapper for Writable instances.A reusableInputStreamimplementation that reads from an in-memory buffer.A WritableComparable for ints.A Comparator optimized for IntWritable.An utility class for I/O related functionality.The /dev/null of OutputStreams.A WritableComparable for longs.A Comparator optimized for LongWritable.A decreasing Comparator optimized for LongWritable.A file-based map from keys to values.Class to merge multiple MapFiles of same Key and Value types to one MapFileProvide access to an existing map.Writes a new map.A Writable Map.A Writable for MD5 hash values.A WritableComparator optimized for MD5Hash keys.Encapsulate a list ofIOExceptioninto anIOExceptionBuild anIOExceptionusingMultipleIOExceptionif there are more than one.Singleton Writable with no data.A Comparator "optimized" for NullWritable.A polymorphic Writable that writes an instance with it's class name.A reusableOutputStreamimplementation that writes to an in-memory buffer.AComparatorthat operates directly on byte representations of objects.Manages a pool of threads which can issue readahead requests on file descriptors.An outstanding readahead request that has been submitted to the pool.This class provides secure APIs for opening and creating files on the local disk.Signals that an attempt to create a file at a given pathname has failed because another file already existed at that path.SequenceFiles are flat files consisting of binary key/value pairs.The compression type used to compress key/value pairs in theSequenceFile.The class encapsulating with the metadata of a file.Reads key/value pairs from a sequence-format file.A tag interface for all of the Reader optionsSorts key/value pairs in a sequence-format file.The interface to iterate over raw keys/values of SequenceFiles.The interface to 'raw' values of SequenceFiles.Write key/value pairs to a sequence-format file.A file-based set of keys.Provide access to an existing set file.Write a new set file.A WritableComparable for shorts.A Comparator optimized for ShortWritable.Sizes of binary values and other some common sizes.SortedMapWritable<K extends WritableComparable<? super K>>A Writable SortedMap.Stringifier<T>Stringifier interface offers two methods to convert an object to a string representation and restore the object given its string representation.This class stores text using standard UTF8 encoding.A WritableComparator optimized for Text keys.A Writable for 2D arrays containing a matrix of instances of a class.Deprecated.replaced by TextA WritableComparator optimized for UTF8 keys.A base class for Writables that provides version checking.Thrown byVersionedWritable.readFields(DataInput)when the version of an object being read does not match the current implementation version as returned byVersionedWritable.getVersion().A WritableComparable for integer values stored in variable-length format.A WritableComparable for longs in a variable-length format.Buffer pool implementation which uses weak references to store buffers in the pool, such that they are garbage collected when there are no references to the buffer during a gc run.A serializable object which implements a simple, efficient, serialization protocol, based onDataInputandDataOutput.AWritablewhich is alsoComparable.A Comparator forWritableComparables.Factories for non-public writables.A factory for a class of Writable.Utility to permit renaming of Writable implementation classes without invalidiating files that contain their class name.