更改列表中的项目并排序然后列出

Question

我想访问对象列表并更改列表中的一些值。之后我想根据日期对列表进行排序。是否可以这样做，我该怎么做呢？

这是我的代码：

public class AccountTransactions {
    private int transactionID;
    private int transactionCode;
    private String transactionDate;
    private String transactionType;
    private String transactionTime;
    private String transactionAmount;
    private String transactionTo;
    private String transactionFrom;

    ... // for bravety

}

Transactions.java：

  public  ListtransactionsObjects getUserTransactions(SearchbyPublicKeyObject publicKeyObject){

        List<AccountTransactions> transactionFrom =  TransactionsRepository.findByTransactionFrom(publicKeyObject.getPublicKey());
        List<AccountTransactions> transactionTo = TransactionsRepository.findByTransactionTo(publicKeyObject.getPublicKey());



  //sudo code
  // loop through list 
  // transactionTo.transactionAmount = "+" + transactionAmount



        List<AccountTransactions> AllTransactions = Stream.concat(transactionFrom.stream(), transactionTo.stream())
                             .collect(Collectors.toList());
    }



 // sort AllTransactions by transactionDate which is of type 05/06/2018

Answer 1

使用Collections.sort作为

// sort AllTransactions by transactionDate which is of type 05/06/2018
Collections.sort(AllTransactions, AccountTransactions::getTransactionDate);

假设您getTransactionDate中的AccountTransactions返回您的交易date（而不是您拥有的string）。 您可能需要将string转换为date.

Answer 2

遍历循环中的对象并设置值。然后使用比较器。

Collections.sort(list, new Comparator<AccountTransactions>() {

        @Override
        public int compare(AccountTransactions o1, AccountTransactions o2) {

          return o1.getTransactionDate().compareTo(o2.getTransactionDate());
        }  
    });

制作日期类型的transactionDate。