com.blazegraph.gremlin.util.Streams Maven / Gradle / Ivy
/**
Copyright (C) SYSTAP, LLC DBA Blazegraph 2006-2016. All rights reserved.
Contact:
SYSTAP, LLC DBA Blazegraph
2501 Calvert ST NW #106
Washington, DC 20008
[email protected]
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; version 2 of the License.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
package com.blazegraph.gremlin.util;
import java.util.Iterator;
import java.util.Spliterator;
import java.util.Spliterators;
import java.util.stream.Stream;
import java.util.stream.StreamSupport;
/**
* Additional Java 8 stream helpers.
*
* @author mikepersonick
*/
public class Streams {
/**
*
* Obtain a Java 8 stream from an iterator. If the iterator happens to
* implement AutoCloseable (e.g. {@link CloseableIterator}), the stream's
* onClose behavior will close the iterator. Thus it is important to
* always close the returned stream, or use within a try-with-resources:
*
*
* {@code
* try (Stream
*
*/
public static final Stream of(final Iterator it) {
final Stream s = StreamSupport.stream(
Spliterators.spliteratorUnknownSize(it, Spliterator.ORDERED), false);
if (it instanceof AutoCloseable) {
final AutoCloseable closeable = (AutoCloseable) it;
s.onClose(() -> Code.wrapThrow(() -> closeable.close()));
}
return s;
}
}