Java Stream Operation endsWith(Stream stream, Iterable iterable)

Description

ends With

License

Open Source License

Declaration

public final static <T> boolean endsWith(Stream<T> stream, Iterable<T> iterable) 

Method Source Code

//package com.java2s;
//License from project: Open Source License 

import java.util.ArrayList;

import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.Objects;

import java.util.Spliterator;
import java.util.Spliterators;

import java.util.stream.Stream;
import java.util.stream.StreamSupport;

public class Main {
    public final static <T> boolean endsWith(Stream<T> stream, Iterable<T> iterable) {
        Iterator<T> it = iterable.iterator();
        List<T> compare1 = new ArrayList<>();
        while (it.hasNext()) {
            compare1.add(it.next());/*from  w  ww . j  a  v  a  2 s  .  co m*/
        }
        LinkedList<T> list = new LinkedList<>();
        stream.forEach(v -> {
            list.add(v);
            if (list.size() > compare1.size())
                list.remove();
        });
        return startsWith(list.stream(), compare1.iterator());

    }

    /**
     * 
     * <pre>{@code 
     * assertTrue(StreamUtils.startsWith(Stream.of(1,2,3,4),Arrays.asList(1,2,3)));
     * }</pre>
     * 
     * @param iterable
     * @return True if Monad starts with Iterable sequence of data
     */
    public final static <T> boolean startsWith(Stream<T> stream, Iterable<T> iterable) {
        return startsWith(stream, iterable.iterator());

    }

    /**
     *    <pre>
     * {@code
     *        assertTrue(StreamUtils.startsWith(Stream.of(1,2,3,4),Arrays.asList(1,2,3).iterator())) 
     * }</pre>
        
     * @param iterator
     * @return True if Monad starts with Iterators sequence of data
     */
    public final static <T> boolean startsWith(Stream<T> stream, Iterator<T> iterator) {
        Iterator<T> it = stream.iterator();
        while (iterator.hasNext()) {
            if (!it.hasNext())
                return false;
            if (!Objects.equals(it.next(), iterator.next()))
                return false;
        }
        return true;

    }

    /**
     * Create a stream from an iterable
     * <pre>
     * {@code 
     *    assertThat(StreamUtils.stream(Arrays.asList(1,2,3))
     *                         .collect(Collectors.toList()),
     *                            equalTo(Arrays.asList(1,2,3)));
        
     * 
     * }
     * </pre>
     * @param it Iterable to convert to a Stream
     * @return Stream from iterable
     */
    public static <U> Stream<U> stream(Iterable<U> it) {
        return StreamSupport.stream(it.spliterator(), false);
    }

    public static <U> Stream<U> stream(Spliterator<U> it) {
        return StreamSupport.stream(it, false);
    }

    /**
     * Create a stream from an iterator
     * <pre>
     * {@code 
     *    assertThat(StreamUtils.stream(Arrays.asList(1,2,3).iterator())   
     *                      .collect(Collectors.toList()),
     *                         equalTo(Arrays.asList(1,2,3)));
        
     * }
     * </pre>
     * @param it Iterator to convert to a Stream
     * @return Stream from iterator
     */
    public static <U> Stream<U> stream(Iterator<U> it) {
        return StreamSupport.stream(Spliterators.spliteratorUnknownSize(it, Spliterator.ORDERED), false);
    }

    /**
     * Create a stream from a map
     * <pre>
     * {@code 
     *    Map<String,String> map = new HashMap<>();
       map.put("hello","world");
       assertThat(StreamUtils.stream(map).collect(Collectors.toList()),equalTo(Arrays.asList(new AbstractMap.SimpleEntry("hello","world"))));
        
     * }</pre>
     * 
     * 
     * @param it Iterator to convert to a Stream
     * @return Stream from a map
     */
    public final static <K, V> Stream<Map.Entry<K, V>> stream(Map<K, V> it) {
        return it.entrySet().stream();
    }
}

Related

1. commaSeparated(Stream stream)
2. concat(IntStream... streams)
3. concat(Stream... streams)
4. containsOnly(Stream stream, long size)
5. createStream(final Iterator iterator)
6. enumerationAsStream(Enumeration e)
7. equals(Stream first, Stream second)
8. factorStream(long number)
9. filterInstances(Stream stream, Class clazz)