列表中的Java流 <Object> 获取任何与filter（）匹配的对象的属性

Question

I want to get the property of any object matching the filter() of the stream, but I am unable to.

transactionsList.stream()
    .filter(transaction -> transaction.getPayerIban() != null)
    .findFirst()
    //Here I get an Optional<Object>
    .ifPresent()
    .map(Transaction::getName)

I don't know what to do inside the .ifPresent() stream operation, but I want to get any transaction name of the matching transactions

Answer 1

Remove the ifPresent() :

Optional<String> optionalName = transactionsList.stream()
    .filter(transaction -> transaction.getPayerIban() != null)
    .findFirst()
    .map(Transaction::getName);