标签:定义 private apply false 条件 har ons 指定 this
/** * 将一个指定类型对象的集合按照自定义的一个操作分组; 每组对应一个List、最终返回结果类型是:List<List<T>> * * @param <T> */ static class GroupToList<T> implements Collector<T, List<List<T>>, List<List<T>>> { /** * 集合中对象两两比较,满足自定义的条件(operation结果返回true),便将这两个元素分为一组 */ private BiFunction<T, T, Boolean> operation; public GroupToList(BiFunction<T, T, Boolean> operation) { super(); this.operation = operation; } @Override public BiConsumer<List<List<T>>, T> accumulator() { return (c, t) -> { boolean added = false; for (List<T> cc : c) { for (T ccc : cc) { if (operation.apply(ccc, t)){ cc.add(t); added = true; } break; } if (added) break; continue; } if (!added) { ArrayList<T> list = new ArrayList<T>(); list.add(t); c.add(list); } }; } @Override public Set<java.util.stream.Collector.Characteristics> characteristics() { /* Set<java.util.stream.Collector.Characteristics> emptySet = Collections.emptySet(); */ return Collections.unmodifiableSet(EnumSet.of(Characteristics.IDENTITY_FINISH)); } @Override public BinaryOperator<List<List<T>>> combiner() { return (l1,l2) -> {l2.addAll(l1); return l2;}; } @Override public Function<List<List<T>>, List<List<T>>> finisher() { return p -> p; } @Override public Supplier<List<List<T>>> supplier() { return () -> new ArrayList<List<T>>(); } }
标签:定义 private apply false 条件 har ons 指定 this
原文地址:https://www.cnblogs.com/mleaf/p/9914336.html