Example usage for java.util.stream Collector Collector

Introduction

In this page you can find the example usage for java.util.stream Collector Collector.

Prototype

Collector

Source Link

Usage

From source file:msi.gama.util.GamaListFactory.java

public static <T> Collector<T, IList<T>, IList<T>> toGamaList() {
    return new Collector<T, IList<T>, IList<T>>() {

        @Override/*from   w w w  . j a  v a 2 s  .  co  m*/
        public Supplier<IList<T>> supplier() {
            return GamaListFactory::create;
        }

        @Override
        public BiConsumer<IList<T>, T> accumulator() {
            return (left, right) -> left.add(right);
        }

        @Override
        public BinaryOperator<IList<T>> combiner() {
            return (left, right) -> {
                left.addAll(right);
                return left;
            };
        }

        @Override
        public java.util.function.Function<IList<T>, IList<T>> finisher() {
            return (left) -> left;
        }

        @Override
        public Set<java.util.stream.Collector.Characteristics> characteristics() {
            return CH;
        }
    };
}

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From source file:com.ikanow.aleph2.data_model.utils.TestCrudUtils.java

private static <T> DBObject convertToMongoQuery_single(String andVsOr, SingleQueryComponent<T> query_in) {
    LinkedHashMultimap<String, Tuple2<Operator, Tuple2<Object, Object>>> fields = query_in.getAll();

    // The actual query:

    return Patterns.match(fields).<DBObject>andReturn().when(f -> f.isEmpty(), f -> new BasicDBObject())
            .otherwise(f -> f.asMap().entrySet().stream()
                    .<Tuple2<String, Tuple2<Operator, Tuple2<Object, Object>>>>flatMap(
                            entry -> entry.getValue().stream().map(val -> Tuples._2T(entry.getKey(), val)))
                    .collect(//ww  w .  ja  v  a 2 s.c om
                            new Collector<Tuple2<String, Tuple2<Operator, Tuple2<Object, Object>>>, BasicDBObject, DBObject>() {
                                @Override
                                public Supplier<BasicDBObject> supplier() {
                                    return BasicDBObject::new;
                                }

                                @Override
                                public BiConsumer<BasicDBObject, Tuple2<String, Tuple2<Operator, Tuple2<Object, Object>>>> accumulator() {
                                    return (acc, entry) -> {
                                        Patterns.match(acc.get(andVsOr)).andAct().when(l -> (null == l), l -> {
                                            BasicDBList dbl = new BasicDBList();
                                            dbl.add(operatorToMongoKey(entry._1(), entry._2()));
                                            acc.put(andVsOr, dbl);
                                        }).when(BasicDBList.class,
                                                l -> l.add(operatorToMongoKey(entry._1(), entry._2())))
                                                .otherwise(l -> {
                                                });
                                    };
                                }

                                // Boilerplate:
                                @Override
                                public BinaryOperator<BasicDBObject> combiner() {
                                    return (a, b) -> {
                                        a.putAll(b.toMap());
                                        return a;
                                    };
                                }

                                @Override
                                public Function<BasicDBObject, DBObject> finisher() {
                                    return acc -> acc;
                                }

                                @Override
                                public Set<java.util.stream.Collector.Characteristics> characteristics() {
                                    return EnumSet.of(Characteristics.UNORDERED);
                                }
                            }));
}

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From source file:org.lightjason.agentspeak.common.CPath.java

/**
 * collector factory/* w w w  .j  a  v  a2 s . com*/
 *
 * @return collector
 */
private static Collector<String, List<String>, List<String>> collectorfactory() {
    return new Collector<String, List<String>, List<String>>() {
        @Override
        public final Supplier<List<String>> supplier() {
            return CopyOnWriteArrayList<String>::new;
        }

        @Override
        public final BiConsumer<List<String>, String> accumulator() {
            return List::add;
        }

        @Override
        public final BinaryOperator<List<String>> combiner() {
            return (i, j) -> {
                i.addAll(j);
                return i;
            };
        }

        @Override
        public final Function<List<String>, List<String>> finisher() {
            return i -> i;
        }

        @Override
        public final Set<Characteristics> characteristics() {
            return Collections.emptySet();
        }
    };
}

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