Double Cannot Be Dereferenced Error
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Double Cannot Be Dereferenced Compareto
Overflow Questions Jobs Documentation Tags Users Badges Ask Question x Dismiss Join the Stack Overflow Community Stack double cannot be dereferenced equals Overflow is a community of 4.7 million programmers, just like you, helping each other. Join them; it only takes a minute: Sign up Double cannot be double cannot be dereferenced java dereferenced? up vote 5 down vote favorite 2 String mins = minsField.getText(); int Mins; try { Mins = Integer.parseInt(mins); } catch (NumberFormatException e) { Mins = 0; } double hours = Mins / 60; hours.setText(hoursminsfield); The problem is that Double cannot be
Int Cannot Be Dereferenced Error In Java
dereferenced. How can I fix this problem? Any help will be appriciated java double share|improve this question edited Apr 23 '12 at 2:06 paxdiablo 489k1179701419 asked Apr 23 '12 at 1:58 Daniel Donaldson 28113 What language is this? Javascript? –Mark Reed Apr 23 '12 at 2:04 Yeh man its java –Daniel Donaldson Apr 23 '12 at 2:06 12 java != javascript –David Gelhar Apr 23 '12 at 2:07 2 @Daniel, I fail to see how the accepted answer relates to
Char Cannot Be Dereferenced Error Java
your question at all. You should have asked another question when you fixed the original problem. –paxdiablo Apr 23 '12 at 2:34 If you want to use hours as double, you have to leave int-arithmetic, which is used, if you mix an int with an literal int like 60: double hours = Mins / 60; Use a literal double like 60.0 instead. –user unknown Apr 23 '12 at 3:24 | show 1 more comment 3 Answers 3 active oldest votes up vote 10 down vote accepted EDIT 4/23/12 double cannot be dereferenced is the error some Java compilers give when you try to call a method on a primitive. It seems to me double has no such method would be more helpful, but what do I know. From your code, it seems you think you can copy a text representation of hours into hoursminfield by doing hours.setText(hoursminfield); This has a few errors: 1) hours is a double which is a primitive type, there are NO methods you can call on it. This is what gives you the error you asked about. 2) you don't say what type hoursminfield is, maybe you haven't even declared it yet. 3) it is unusual to set the value of a variable by having it be the argument to a method. It happens sometimes, but not usually. The lines of code that do what you seem to want are: String hoursrminfield; // you better declare any variable you are using // wrap hours in a Double, then use toString(
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Java Long Cannot Be Dereferenced
Learn more about hiring developers or posting ads with us Stack Overflow Questions Jobs Documentation Tags Users Badges Ask double cannot be dereferenced intvalue Question x Dismiss Join the Stack Overflow Community Stack Overflow is a community of 4.7 million programmers, just like you, helping each other. Join them; it only takes a minute: Sign http://stackoverflow.com/questions/10273949/double-cannot-be-dereferenced up “double Cannot be Dereferenced” toString() - does this alternative form without errors mean the same thing? up vote 0 down vote favorite In the following snippet of code the int returns properly, but when I try doing the same thing with a double NetBeans 8.0.2 complains that "double Cannot be Dereferenced" The non-commented out variables work. The commented out variables are double http://stackoverflow.com/questions/32741911/double-cannot-be-dereferenced-tostring-does-this-alternative-form-without and do not work. @Override public String toString() { return "[" + getAccountNumber() + "], " + super.toString() + ", " + owner.toString() // Error: "Double Cannot be Dereferenced" why? // + ", " + currentBalance.toString() // + ", " + interestRate.toString() ; } When I rewrite it like this NetBeans doesn't give me an error, but is this effectively the same thing for a double? @Override public String toString() { return "[" + getAccountNumber() + "], " + super.toString() + ", " + owner.toString() // Error: "Double Cannot be Dereferenced" // + ", " + currentBalance.toString() // + ", " + interestRate.toString() // The following seems to work instead: + ", " + Double.toString(currentBalance) + ", " + Double.toString(interestRate) ; } If so, great. No errors. If not, what can I do to make sure that the value of a double returns to the String just as an int would? UPDATE: From the answers I received, it looks like second approach I used works, but the following works just as well: @Override public String toString() { return "[" + getAccountNumber() + "], " + super.toString
here for a quick overview of the site Help Center Detailed answers to any questions you might have Meta Discuss the workings and http://stackoverflow.com/questions/18691643/double-cannot-be-dereferenced policies of this site About Us Learn more about Stack Overflow the http://www.dreamincode.net/forums/topic/286310-double-cannot-be-dereferenced/ company Business Learn more about hiring developers or posting ads with us Stack Overflow Questions Jobs Documentation Tags Users Badges Ask Question x Dismiss Join the Stack Overflow Community Stack Overflow is a community of 4.7 million programmers, just like you, helping each other. Join them; it only takes cannot be a minute: Sign up Double cannot be dereferenced…? up vote 1 down vote favorite import java.awt.Rectangle; import java.util.Comparator; public class RectangleComparator implements Comparator { public int compare(Object object1, Object object2) { Rectangle rec1 = (Rectangle) object1; Rectangle rec2 = (Rectangle) object2; return rec1.getWidth().compareTo(rec2.getWidth()); } } For some reason, I'm getting the error double cannot be dereferenced. Can anyone help me figure out cannot be dereferenced why? java share|improve this question edited Sep 9 '13 at 4:56 asked Sep 9 '13 at 4:50 user2760309 3314 BTW, it's rarely a good idea to compare float/double values for exact equality. See stackoverflow.com/questions/4915462/… –sleske Sep 9 '13 at 5:00 add a comment| 3 Answers 3 active oldest votes up vote 3 down vote accepted rocketboy is correct with regard to why this is happening. Consider using the Double wrapper class like this new Double(rec1.getWidth()).compareTo(rec2.getWidth()); Only the first value need to be converted to a wrapper Double, the second one will be auto boxed. share|improve this answer answered Sep 9 '13 at 4:56 Thihara 4,99411538 1 You should not use new Double(…) at all. Please get into the habit of using Double.valueOf(…) as this will allow Java to reuse existing objects. Of course that’s even more important for small integers or longs. –Michael Piefel Sep 9 '13 at 6:39 @MichaelPiefel Does this depend on the implementation or am I missing something? The Double.valueOf(double d) seem to be just calling new Double(double d) under the wraps. –Thihara Sep
12 Replies - 6207 Views - Last Post: 23 July 2012 - 05:30 AM Rate Topic: #1 BlackFiredDragon New D.I.C Head Reputation: 0 Posts: 32 Joined: 19-July 12 double cannot be dereferenced Posted 19 July 2012 - 09:10 AM I have an error with this code. It was supposed to use the binary search method in order to find the number 45.3 in this array: [-3, 10, 5, 24, 45.3, 10.5}. At first everything was OK. But then I had a problem with the decimals - because I used 'int'. So I changed a few things and made it 'double' instead of int. Now I get these errors: program-3.java:12: error: double cannot be dereferenced if (a[mid].compareTo (x)<0) ^ program-3.java:14: error: double cannot be dereferenced else if (a[mid].compareTo (x) > 0) ^ 2 errors This is my code: class Binarys { public static final int NOT_FOUND = -1; public static double binarys(double[] a, double x) { int low=0; int high = a.length - 1; int mid; while (low <= high) { mid = (low + high) / 2; if (a[mid].compareTo (x)<0) low = mid + 1; else if (a[mid].compareTo (x) > 0) high = mid - 1; else return mid; } return NOT_FOUND; } public static void main(String[] args) { double[] array = {-3, 10, 5, 24, 45.3, 10.5}; int l = array.length; int a; System.out.println("Original Numbers:"); for (a = 0; a < l; a++ ) { System.out.println(array[a]); } System.out.println("45.3 found at " + binarys(array, 45.3)); } } Please help me with this problem, it's been stuck with me for several days. Thank you! Is This A Good Question/Topic? 0 Back to top MultiQuote Quote + Reply Replies To: double cannot be dereferenced #2 macosxnerd101 Games, Graphs, and Auctions Reputation: 11994 Posts: 44,812 Joined: 27-December 08 Re: double cannot be dereferenced Posted 19 July 2012 - 09:12 AM You can't invoke methods or reference fields on primitives. Since these are numbers, just directly compare them using the >, >= , <, <=, ==, and != operators. You don't need the compareTo() method. Was This Post Helpful? 1 Back to top MultiQuote Quote + Reply #3 Ryano121 D.I.C Lover Reputati