it.unimi.dsi.io

Class OfflineIterable<T,U extends T>

java.lang.Object

it.unimi.dsi.io.OfflineIterable<T,U>

All Implemented Interfaces:

SafelyCloseable, Closeable, AutoCloseable, Iterable<U>

public class OfflineIterable<T,U extends T>
extends Object
implements Iterable<U>, SafelyCloseable

An iterable that offers elements that were previously stored offline using specialized serialization methods. At construction, you provide a serializer that establishes how elements are written offline; after that, you can add elements one at a time or in a bulk way. At any moment, you can get an OfflineIterator on this object that returns all the elements added so far. Note that the returned iterator caches the current number of elements, so each iterator will return just the elements added at the time of its creation.

Warning: The store object provided at construction time is shared by all iterators.

Closing

Both OfflineIterable and OfflineIterator are SafelyCloseable (the latter will close its input stream when hasNext() returns false), but for better resource management you should close them after usage.

Store reuse

Since:

0.9.2

Author:

Sebastiano Vigna

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	OfflineIterable.OfflineIterator<A,B extends A> An iterator returned by an OfflineIterable.
static interface	OfflineIterable.Serializer<A,B extends A> Determines a strategy to serialize and deserialize elements.

Field Summary

Fields

Modifier and Type	Field and Description
static long	serialVersionUID

Constructor Summary

Constructors

Constructor and Description
OfflineIterable(OfflineIterable.Serializer<? super T,U> serializer, U store) Creates an offline iterable with given serializer.

Method Summary

Methods

Modifier and Type	Method and Description
void	add(T x) Adds a new element at the end of this iterable.
void	addAll(Iterable<T> it) Adds all the elements of the given iterable at the end of this iterable.
void	close()
protected void	finalize()
OfflineIterable.OfflineIterator<T,U>	iterator()
long	length() Returns the number of elements added so far.
int	size() Returns the number of elements added so far, unless it is too big to fit in an integer (in which case this method will throw an exception).

Methods inherited from class java.lang.Object

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

Field Detail

serialVersionUID

public static final long serialVersionUID

See Also:

Constant Field Values

Constructor Detail

OfflineIterable

public OfflineIterable(OfflineIterable.Serializer<? super T,U> serializer,
               U store)
                throws IOException

Creates an offline iterable with given serializer.

Parameters:

serializer - the serializer to be used.

store - an object that is (re)used by the iterator(s) iterating on this iterable.

Throws:

IOException

Method Detail

add

public void add(T x)
         throws IOException

Adds a new element at the end of this iterable.

Parameters:

x - the element to be added.

Throws:

IOException

addAll

public void addAll(Iterable<T> it)
            throws IOException

Adds all the elements of the given iterable at the end of this iterable.

Parameters:

it - the iterable producing the elements to be added.

Throws:

IOException

iterator

public OfflineIterable.OfflineIterator<T,U> iterator()

Specified by:

iterator in interface Iterable<U extends T>

close

public void close()

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

finalize

protected void finalize()
                 throws Throwable

Overrides:

finalize in class Object

Throws:

Throwable

size

public int size()

Returns the number of elements added so far, unless it is too big to fit in an integer (in which case this method will throw an exception).

Returns:

the number of elements added so far.

length

public long length()

Returns the number of elements added so far.

Returns:

the number of elements added so far.