Results 1 to 14 of 14
  1. #1
    skiing is offline Member
    Join Date
    Nov 2008
    Posts
    15
    Rep Power
    0

    Default [SOLVED] String conversion

    I am trying to convert a string that is a float value to a float then add 25.00 to it and convert it back to a string. I have tried the following.

    String balance = rs.getString(9);

    float price = Integer.parseInt(balance);
    // val = price + 25;
    // String ic = Integer.toString(val)

  2. #2
    Fubarable's Avatar
    Fubarable is offline Moderator
    Join Date
    Jun 2008
    Posts
    19,316
    Blog Entries
    1
    Rep Power
    26

    Default

    You use Integer to parse a String to an int not a float or double. Since Integer is the wrapper class for int, what class should you use to parse a String to float?

    Hint: Look in the API and you will find the class and your method.

    Also, you rarely want to use float when you can use the more accurate double type.

  3. #3
    Eranga's Avatar
    Eranga is offline Moderator
    Join Date
    Jul 2007
    Location
    Colombo, Sri Lanka
    Posts
    11,372
    Blog Entries
    1
    Rep Power
    19

    Default

    You have made few mistakes there.

    Java Code:
            String str = "34.2";
            float val = Float.parseFloat(str);
            float newVal = val + 25.0F;
            str = String.valueOf(newVal);
            System.out.println(str);

  4. #4
    Fubarable's Avatar
    Fubarable is offline Moderator
    Join Date
    Jun 2008
    Posts
    19,316
    Blog Entries
    1
    Rep Power
    26

    Default

    OK, Eranga has given you the answer: to get a float from a String you need to use the Float class and parse it with a parseFloat method. I again recommend however that you not do this, but instead use Double.parseDouble(...)

  5. #5
    Eranga's Avatar
    Eranga is offline Moderator
    Join Date
    Jul 2007
    Location
    Colombo, Sri Lanka
    Posts
    11,372
    Blog Entries
    1
    Rep Power
    19

    Default

    Yes, that's true. But there is a reason not to mentioned that in my post. Because our thread starter can confuse on float and double. Just look at his attempt. Seems no idea about wrapper classes, he's a newbie to Java. :)

  6. #6
    fishtoprecords's Avatar
    fishtoprecords is offline Senior Member
    Join Date
    Jun 2008
    Posts
    571
    Rep Power
    7

    Default

    Quote Originally Posted by Fubarable View Post
    Also, you rarely want to use float when you can use the more accurate double type.
    For currency, using a double is not much more accurate than a float. And while the OP is new to Java, its never too soon to remember:

    Using a float or double for money/currency is a sin.

    Don't do it!

  7. #7
    Fubarable's Avatar
    Fubarable is offline Moderator
    Join Date
    Jun 2008
    Posts
    19,316
    Blog Entries
    1
    Rep Power
    26

    Default

    fishtoprecords is absolutely correct. I didn't see that the OP was dealing with currency here.

  8. #8
    Eranga's Avatar
    Eranga is offline Moderator
    Join Date
    Jul 2007
    Location
    Colombo, Sri Lanka
    Posts
    11,372
    Blog Entries
    1
    Rep Power
    19

    Default

    And if I'm remember correctly, fishtoprecords took a long discussion about that in one of his past thread. Sorry if I'm wrong.

  9. #9
    fishtoprecords's Avatar
    fishtoprecords is offline Senior Member
    Join Date
    Jun 2008
    Posts
    571
    Rep Power
    7

  10. #10
    Eranga's Avatar
    Eranga is offline Moderator
    Join Date
    Jul 2007
    Location
    Colombo, Sri Lanka
    Posts
    11,372
    Blog Entries
    1
    Rep Power
    19

    Default

    I think it's better to look at our thread starter. May be even before he has to learn about basis as well.

  11. #11
    jhen is offline Member
    Join Date
    Nov 2008
    Posts
    12
    Rep Power
    0

    Default polymorphism

    can anyone give me a simple source code that demonstrates polymorphism in java?

    anyone plz:o

  12. #12
    Fubarable's Avatar
    Fubarable is offline Moderator
    Join Date
    Jun 2008
    Posts
    19,316
    Blog Entries
    1
    Rep Power
    26

    Default

    Quote Originally Posted by jhen View Post
    can anyone give me a simple source code that demonstrates polymorphism in java?

    anyone plz:o
    Please don't hijack another thread. if you have a question, post it in its own thread.

  13. #13
    skiing is offline Member
    Join Date
    Nov 2008
    Posts
    15
    Rep Power
    0

    Default Thanks

    It works now.

  14. #14
    Eranga's Avatar
    Eranga is offline Moderator
    Join Date
    Jul 2007
    Location
    Colombo, Sri Lanka
    Posts
    11,372
    Blog Entries
    1
    Rep Power
    19

    Default

    Quote Originally Posted by jhen View Post
    can anyone give me a simple source code that demonstrates polymorphism in java?

    anyone plz:o
    Please don't deal with others thread, if your question is not related to. Start on separate thread in the correct sub-forum.

Similar Threads

  1. String to Integer Conversion in JSP
    By vinikz in forum New To Java
    Replies: 8
    Last Post: 11-10-2010, 02:45 PM
  2. String to Object conversion
    By moaxjlou in forum New To Java
    Replies: 1
    Last Post: 10-29-2008, 01:04 AM
  3. string conversion??
    By j2vdk in forum New To Java
    Replies: 13
    Last Post: 09-19-2008, 03:35 PM
  4. bytearray to string conversion
    By mew in forum New To Java
    Replies: 1
    Last Post: 01-28-2008, 10:39 AM
  5. String to Date conversion
    By javaplus in forum New To Java
    Replies: 2
    Last Post: 11-06-2007, 07:16 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •