I am working on a method where I’ve written the following line here: As you can see from the TrackingCategoryTransformationClient class below, this yields an error as the abstract method getErpListDataById returns Optional<AccountingObject> and not Optional<TrackingCategory> which is what th…
Tag: type-conversion
Convert pdf to Postscript using Java
I recently posted a question how to convert a PDF byte[] to Postscript. According to comment, it’s not possible. I was anyway looking into this other question on how to transform a pdf to Postscript. But still cannot get it working. I got my PDF saved already, how would I get an already existing PDF con…
Is it possible to convert the String “1L” to the corresponding Long value?
I am parsing a config file with the following instructions: The returned value, that is a String, is later converted into the expected type from the calling method. How can I convert the String 1L into a Long type? I tried: but it raises NumberFormatException. Is there a way to do it? Answer Neither Long.pars…
How to restore initial fraction from a big decimal
I have a list of fractions that have to be converted to a bigDecimal first and then converted to a fraction again. I have made two methods: first converts from fraction to bigDecimal and the second does the opposite. However, I have noticed that during the conversion I am losing on some precision, hence I was…
Use MapStruct to convert member variable to id (and vice versa)
In my SpringBoot application, I have two entities User and Role with My DTOs looked quite similar until I realized this could lead to a recursion problem, when a user has a field role which has a field of the same user, which has a field of the same role, etc. Therefore I decided to hand only the ids my
How do I convert an Int to an Int[] in java?
I want to convert a primitive Java integer value: To an integer array: Answer There can be so many ways to do it. A concise way of doing it’s using Stream API as shown below: Output: Notes: ASCII value of ‘0’ is 48, that of ‘1’ is 49 and so on. Math#abs returns the absolute value…
Java – White space with Integer.valueOf() causes java.lang.NumberFormatException [closed]
Closed. This question is opinion-based. It is not currently accepting answers. Want to improve this question? Update the question so it can be answered with facts and citations by editing this post. Closed 2 years ago. Improve this question If you try: Integer.valueOf(” 00″); …a java.lang.Nu…
How to convert short[] into List in Java with streams?
I figured I could extrapolate from this question but I can’t I can of course do But I’m wondering how to do it with streams. doesn’t work for example but yields The method stream(T[]) in the type Arrays is not applicable for the arguments (short[]) Answer Why not
Cannot invoke charAt(int) on the array type String[]
I’m doing a function that counts digits in a string: The error is: Any ideas how to fix that? Answer You are trying to invoke the charAt() method on a String[]. String[] does not have such a method, but String does. What I believe you wanted to do is: This will get the char at position i in the String
Error converting Optional to Integer from TextInputDialog
In this example I have tempSocket1 and tempSocket2 but I really just want one of them. I just included both to show I tried both methods, but I keep getting an error, “the method valueOf(String) in the type Integer is not applicable for the arguments (Optional).” I thought both of these methods we…