lambda toMap高阶使用

import java.util.function.Function;
import java.util.stream.Collectors;

Map<String, String> map = result.getData().stream().collect(Collectors.toMap(CustomerExtendDto::getCustomerCode, CustomerExtendDto::getCustomerName, (n1, n2) -> n1));

Map<String, SourceCodeRoute> existRouteUrlMap = bySourceCodeAndRouteUrlList.stream().collect(Collectors.toMap(SourceCodeRoute::getRouteUrl, Function.identity()));

Map<String, CustomerWebDTO> customerMap = result.getData().stream().collect(Collectors.toMap(CustomerWebDTO::getCustomerCode, customerWebDTO -> customerWebDTO, (n1, n2) -> n1));