Question

我正在尝试创建一个返回通用表达式列表的方法。

在基于某些条件的中间我创建特定类型的ExpressionList，最后我想将ExpressionList转换为通用ExpressionList。但是，不幸的是我一直坚持转换。

下面是代码snipet。

我正在尝试创建一个返回通用表达式列表的方法。

在基于某些条件的中间我创建特定类型的ExpressionList，最后我想将ExpressionList转换为通用ExpressionList。但是，不幸的是我一直坚持转换。

下面是代码snipet。

  public static <T> ExpressionList<T> generateTransactionList(Map<String,String[]> params, Party party){

    String filter = "";

    Date startDate = new Date(params.get("startDate")[0]);
    Date endDate = new Date(params.get("endDate")[0]+" 23:59:59");
    //endDate.setDate(endDate.getDate() + 1);

    ExpressionList<TypeOne> TypeOneExpressionList = null;
    ExpressionList<TypeTwo> TypeTwoResponseExpressionList = null;
    if(settleState == 3) {
        TypeTwoResponseExpressionList = TypeTwo.find.select("*").where()
                .between("response_date", startDate, endDate)
                .eq("status", "failed");
    }
    else {
                acquiringTransactionExpressionList = AcquiringTransaction.find.select("*").where()
                    .between("transactionTime", startDate, endDate)
                    .ne("acquiringTransactionStatusType.id", 99);

            }

    ExpressionList<T> returningTypeOneExpressionList = null;
    Class<T> convert = null;
    if(TypeOneExpressionList != null) {
        TypeOneExpressionList.orderBy("id desc"  );
        Iterator<TypeOne> iterator = TypeOneExpressionList.findIterate();
        while(iterator.hasNext()) {
            returningTypeOneExpressionList.add((Expression) convert.cast(iterator.next()));
        }
    }
    else {
        TypeTwoResponseExpressionList.orderBy("id desc"  );
        Iterator<TypeTwo> iterator = TypeTwoResponseExpressionList.findIterate();
        while(iterator.hasNext()) {
            returningTypeOneExpressionList.add((Expression) convert.cast(iterator.next()));
        }
    }
    return returningTypeOneExpressionList;
}

提前致谢。

Answer 1

我找到了答案，而且我之前没有尝试过，这真的很糟糕。

我刚刚在代码中进行了以下更改。

  public static <T> ExpressionList<T> generateTransactionList(Map<String,String[]> params, Party party){

String filter = "";

Date startDate = new Date(params.get("startDate")[0]);
Date endDate = new Date(params.get("endDate")[0]+" 23:59:59");
//endDate.setDate(endDate.getDate() + 1);

ExpressionList<TypeOne> TypeOneExpressionList = null;
ExpressionList<TypeTwo> TypeTwoResponseExpressionList = null;
if(settleState == 3) {
    TypeTwoResponseExpressionList = TypeTwo.find.select("*").where()
            .between("response_date", startDate, endDate)
            .eq("status", "failed");
}
else {
            acquiringTransactionExpressionList = AcquiringTransaction.find.select("*").where()
                .between("transactionTime", startDate, endDate)
                .ne("acquiringTransactionStatusType.id", 99);

        }

ExpressionList<T> returningAcquiringTransactionExpressionList = null;
    Class<T> convert = null;
    if(acquiringTransactionExpressionList != null) {
        acquiringTransactionExpressionList.orderBy("id desc"  );

            returningAcquiringTransactionExpressionList = (ExpressionList<T>) acquiringTransactionExpressionList;

    }
    else {
        acquiringTransactionResponseExpressionList.orderBy("id desc"  );
        returningAcquiringTransactionExpressionList = (ExpressionList<T>) acquiringTransactionResponseExpressionList;
    }
return returningTypeOneExpressionList;

}

如何将特定类型的ExpressionList转换为泛型

1 个答案: