AppletTalk.com Java discussions newsgroups   Archives   FAQ   Search   Memberlist   Usergroups   Register   Profile   Log in to check your private messages   Log in  2D array          AppletTalk.com Forum Index -> Java Help View previous topic :: View next topic   Author Message Terence Guest Posted: Wed Mar 03, 2004 12:22 pm    Post subject: 2D array help !! can somebody know what's wrong with this 2 D array ... private static final String[] users = { "Alice,20020115,100,20020314,-2,20020520,50,20030220,-34,20030724,-10,200308 01,5", "Bob,20020213,98,20020422,-4,20020611,60,20030310,-43,20030807,-9,20030904,6 ", "Chris,20020317,10,20020521,30,20020601,5,20030320,-10,20030907,8,20031004,1 0"}; String[][] a = new String[2][5]; for (int i=0; i<5;i++) { int end_pos; int start_pos=0; for (int j=0;j<2;j++) { end_pos=users[i].indexOf(',',start_pos); a[i][j]=users[j].substring(start_pos,end_pos); start_pos=end_pos++; a[i][j]=""; } } Back to top Ryan Stewart Guest Posted: Wed Mar 03, 2004 12:41 pm    Post subject: Re: 2D array "Terence" <terence_38i (AT) hotmail (DOT) com> wrote Quote: help !! can somebody know what's wrong with this 2 D array ... private static final String[] users = { "Alice,20020115,100,20020314,-2,20020520,50,20030220,-34,20030724,-10,200308 01,5", "Bob,20020213,98,20020422,-4,20020611,60,20030310,-43,20030807,-9,20030904,6 ", "Chris,20020317,10,20020521,30,20020601,5,20030320,-10,20030907,8,20031004,1 0"}; String[][] a = new String[2][5]; for (int i=0; i<5;i++) { int end_pos; int start_pos=0; for (int j=0;j<2;j++) { end_pos=users[i].indexOf(',',start_pos); a[i][j]=users[j].substring(start_pos,end_pos); start_pos=end_pos++; a[i][j]=""; } } The first problem that springs to mind is that we need more information. A compilable example is preferable, and your question is vague at best. Describe what's happening and what you want to happen and any errors you may be getting. For tips see: http://www.physci.org/codes/sscce.jsp For a start in the problem area, on the second (code) line of your inner for loop, you try to access a[i][j], which is a String[2][5]. But the range of i is 0 to 4, so when i reaches 2, you'll receive an IndexOutOfBoundsException on this line. Back to top Gregory A. Swarthout Guest Posted: Wed Mar 03, 2004 7:48 pm    Post subject: Re: 2D array "Terence" <terence_38i (AT) hotmail (DOT) com> wrote Quote: help !! can somebody know what's wrong with this 2 D array ... private static final String[] users = { "Alice,20020115,100,20020314,-2,20020520,50,20030220,-34,20030724,-10,200308 01,5", "Bob,20020213,98,20020422,-4,20020611,60,20030310,-43,20030807,-9,20030904,6 ", "Chris,20020317,10,20020521,30,20020601,5,20030320,-10,20030907,8,20031004,1 0"}; String[][] a = new String[2][5]; for (int i=0; i<5;i++) { int end_pos; int start_pos=0; for (int j=0;j<2;j++) { end_pos=users[i].indexOf(',',start_pos); a[i][j]=users[j].substring(start_pos,end_pos); Here you are setting an element to a substring of users[j]. Quote: start_pos=end_pos++; a[i][j]=""; Here you are setting the same element to an empty string. Quote: } } What is the problem/error you are experiencing? Greg Back to top Tony Morris Guest Posted: Wed May 12, 2004 7:58 am    Post subject: Re: 2D array "D. Beckham" <lekhanh88 (AT) earthlink (DOT) net> wrote Quote: Would someone shows me the java syntax to create a 2D array of a calendar, where the rows represents months, such as: Jan, Feb... and columns represent days; assuming that there are 29 days in Feb? I don't know whether to declare this 2D array in String or int, since the months are string while days are int. Thanks Java does not have 2D arrays. It has arrays of arbitrary type, whose elements may be arrays i.e. arrays of arrays. This distinction is important, not academic/pedantic (I care not to describe why). At the end of the day, it will be you who does your homework, not some arbitrary person on a newsgroup, since it is intended for you to learn. http://java.sun.com/docs/books/tutorial/java/data/arrays.html Good luck. -- Tony Morris (BInfTech, Cert 3 I.T., SCJP[1.4], SCJD) Software Engineer IBM Australia - Tivoli Security Software (2003 VTR1000F) Back to top Roedy Green Guest Posted: Wed May 12, 2004 9:06 am    Post subject: Re: 2D array On Wed, 12 May 2004 06:27:33 GMT, "D. Beckham" <lekhanh88 (AT) earthlink (DOT) net> wrote or quoted : Quote: Would someone shows me the java syntax to create a 2D array of a calendar, where the rows represents months, such as: Jan, Feb... and columns represent days; assuming that there are 29 days in Feb? I don't know whether to declare this 2D array in String or int, since the months are string while days are int. Thanks I posted some code to create a calendar in HTML earlier today in comp.lang gui in the thread "need help with 2D array". you could take that and combine it with the code in http://mindprod.com/jgloss/gotchas.html#MATRIX to creata a matrix of objects of days, including dummies on front and end so that grid always starts with Sunday. -- Canadian Mind Products, Roedy Green. Coaching, problem solving, economical contract programming. See http://mindprod.com/jgloss/jgloss.html for The Java Glossary. Back to top RC Guest Posted: Wed May 12, 2004 2:07 pm    Post subject: Re: 2D array D. Beckham wrote: Quote: Would someone shows me the java syntax to create a 2D array of a calendar, where the rows represents months, such as: Jan, Feb... and columns represent days; assuming that there are 29 days in Feb? I don't know whether to declare this 2D array in String or int, since the months are string while days are int. Thanks int calArray[][] = new int[12][31]; calArray[0] = Calendar.JANUARY; // it is int, not String .... calArray[11] = Calendar.DECEMBER; Or calArray[0] = 0; // MONTH .... calArray[11] = 11; calArray[][0] = 1; // DAY_OF_MONTH .... calArray[][30] = 31; Note, Calendar.MONTH is from 0 to 11 and Calendar.DAY_OF_MONTH is from 1 to 31 Back to top Display posts from previous: All Posts1 Day7 Days2 Weeks1 Month3 Months6 Months1 Year Oldest FirstNewest First         AppletTalk.com Forum Index -> Java Help All times are GMT Page 1 of 1   Jump to: Select a forum Java Newsgroups----------------Java DiscussionsWeb-based java games comp.lang.java 3D Graphics API's for Java Java: Support and criticism Java System Announcements comp.lang.java.api JavaBeans Java and CORBA Java and Databases comp.lang.java.developer Java GUI Toolkits Java Help comp.lang.java.javascript JVM, native methods and hardware comp.lang.java.misc Java Language Programming Security and Java comp.lang.java.setup Java Software Tools comp.lang.java.tech ibm.software.java.linux  Non-English Java Newsgroups----------------Java Language (German)Language Java (Français)Java (Italian)  You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum Powered by phpBB © 2001, 2006 phpBB Group SEO toolkit © 2004-2006 webmedic.