Java 8 的排序、取值实现List transactionsIds = transactions.parallelStream().
filter(t -> t.getType() == Transaction.GROCERY).
sorted(comparing(Transaction::getValue).reversed()).
map(Transaction::getId).
collect(toList());
//1.jdk8 lambda排序，带参数类型
orderList.sort(( Order ord1, Order ord2) -> ord2.getOrderId().compareTo(ord1.getOrderId()));
//2.jdk8 lambda排序，不带参数类型
orderList.sort(( ord1, ord2) -> ord2.getOrderId().compareTo(ord1.getOrderId()));
//3.jdk8 升序排序，Comparator提供的静态方法
Collections.sort(orderList, Comparator.comparing(Order::getOrderId));
//4.jdk8 降序排序，Comparator提供的静态方法
Collections.sort(orderList, Comparator.comparing(Order::getOrderId).reversed());
//5.jdk8 组合排序，Comparator提供的静态方法，先按orderId排序，orderId相同的按userId排序
Collections.sort(orderList, Comparator.comparing(Order::getOrderId).reversed().thenComparing(Order::getUserId));
orderList.stream().forEach(str -> System.out.println(str.getOrderId()+"/" + str.getUserId()));
}
}
标签：void.sotor.comintjavasystem[]demo
原文地址：https://www.cnblogs.com/WAbby/p/9249833.html
