org.ontoware.rdf2go.util

Class Iterators

java.lang.Object

org.ontoware.rdf2go.util.Iterators

public class Iterators
extends Object

This class consists exclusively of static methods that operate on or return iterators. It is the Iterator-equivalent of java.util.Collections. copied into RDF2Go by Leo Sauemann on 11.1.2007, it helps to get working quicker.

Constructor Summary

Constructors

Constructor and Description
Iterators()

Method Summary

Modifier and Type	Method and Description
static <E,C extends Collection<E>> C	addAll(Iterator<? extends E> iter, C collection) Adds all elements from the supplied iterator to the specified collection.
static void	closeCloseable(Iterator<?> iter) Closes the supplied iterator if it is an instance of ClosableIterator, otherwise the request is ignored.
static int	count(Iterator<?> it) Runs through the iterator and returns number of items.
static String	toString(Iterator<?> iter, String separator) Converts an iterator to a string by concatenating all of the string representations of objects in the iterator, divided by a separator.
static void	toString(Iterator<?> iter, String separator, StringBuilder sb) Converts an iterator to a string by concatenating all of the string representations of objects in the iterator, divided by a separator.

Methods inherited from class java.lang.Object

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

Constructor Detail

Iterators

public Iterators()

Method Detail

addAll

public static <E,C extends Collection<E>> C addAll(Iterator<? extends E> iter,
                                                   C collection)

Adds all elements from the supplied iterator to the specified collection. If the supplied iterator is an instance of ClosableIterator it is automatically closed after consumption.

Parameters:

iter - An iterator containing elements to add to the container. If the iterator is an instance of ClosableIterator it is automatically closed after consumption.

collection - The collection to add the elements to.

Returns:

The collection object that was supplied to this method.

closeCloseable

public static void closeCloseable(Iterator<?> iter)

Closes the supplied iterator if it is an instance of ClosableIterator, otherwise the request is ignored.

Parameters:

iter - The iterator that should be closed.

toString

public static String toString(Iterator<?> iter,
                              String separator)

Converts an iterator to a string by concatenating all of the string representations of objects in the iterator, divided by a separator.

Parameters:

iter - An iterator over arbitrary objects that are expected to implement Object.toString().

separator - The separator to insert between the object strings.

Returns:

A String representation of the objects provided by the supplied iterator.

toString

public static void toString(Iterator<?> iter,
                            String separator,
                            StringBuilder sb)

Converts an iterator to a string by concatenating all of the string representations of objects in the iterator, divided by a separator.

Parameters:

iter - An iterator over arbitrary objects that are expected to implement Object.toString().

separator - The separator to insert between the object strings.

sb - A StringBuilder to append the iterator string to.

count

public static int count(Iterator<?> it)

Runs through the iterator and returns number of items. It doesn't close it.

Parameters:

it - Any type of iterator, not null