Using concat for STrings

I'm trying to concat a specified string, ".jpg", to a string of the form:
filestring = afile.getName();
filestring.concat(".jpg");
Why does it not add the .jpg to the end of what filestring is?

Cuz Strings are immutable dingbat. If you'd read the api you might notice concat returns a new string with the value you want, but you're chucking it since you didn't assign the result to a variable.
Options:
1) filestring = afile.getName() + ".jpg"
2) filestring = afile.getName().concat(".jpg");
3) filestring = afile.getName(); filestring = filestring.concat(".jpg");
3) use StringBuffer instead

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Question of using concat for databinding

I am trying to use concat to build up a string for databinding. the code 2 should replace the code 1 here and of course they should have the same output:
Code 1:
<textInput text="${uix.current.DepartmentName}"
             columns="10" readOnly="true"/>
Code2:
     <textInput columns="10" readOnly="true">
      <boundAttribute name="text">
         <dataObject>
           <concat>
              <![CDATA[${uix.current.]]>
              <![CDATA[DepartmentName]]>
              <![CDATA[}]]>
           </concat>
         </dataObject>
       </boundAttribute>
   </textInput>Code 1 gives out always right out put like "Administration,Marketing...." ,but code 2 gives always "${uix.current.DepartmentName}", the databinding code out. Its not translated correctly as databinding resourse.
Do You have any idea to solve this problem?
Best Regards
Yong

Hi Arjuna, thanks for your help.
We are currently investigating how to extend the UIX components in a way to get the good old bc4j components back again.
We had some understanding problems with the new binding.
Anyhow a <textInput text="${uix.current[uix.rootAttr.attrName]}}" /> seems to work.
Regards, Markus

Use Operator == for String Comparison

Hi,
I would like to know more about the impact of using operator == in String Comparison.
From the reference I get, it state this :
"Operator (==) compares two object addresses to see whether it refers to the same object."
I've tested it with 2 codes as below :
Code 1:
          String Pass1 = "cosmo";
          String Pass2 = "cosmo";
if (Pass1==Pass2)
               System.out.println("1&2:same");
          else
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Output : 1&2:same
Code 2:
          String Pass3 = new String("cosmo");
          String Pass4 = new String("cosmo");
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Can anyone kindly explain why is the result so? If operator == compares the addresses, isn't it that the 1st code should also have the output :"1&2:not same".

Can anyone kindly explain why is the result so?It's an implementation artifact. Strings are pooled internally and because of that any String literal will be represented by exactly one object reference.
Knowledge of this shouldn't be utilized though. It's safer to follow the basic rule: Use == to compare object references and equals to compare object values, such as String literals.

Using StartsWith for String Comparision in Business rules

hi,
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defined the set. Now, I hoped to use the String.StartsWith() method but couldn't understand if it can be used.
As of now, we are creating a method and that will be called with 2 parameters. One the string and other is one of the list of values which we want the string to start with. Is there any better way to do this?
Praveen Behara
MCST : BizTalk Server 2006 R2, 2010

Hi Murugesan,
I need to match a particular series of numbers... say 12xxx,345xxx,567xxx. I am creating a
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Praveen Behara
MCST : BizTalk Server 2006 R2, 2010

Using wildcards for String compare

Hello,
I want my prog to find out all Strings which start with the letters 'File'. How can I make a String compare by using wildcards ?
Thanx,
Findus

You may use the String method startsWith to find strings beginning with File. eg. filename.startsWith("File")
for more complicated comparisons you might want to use regular expressions.

Using CharAt for String Manipulation

Hi,
I am new to Java and am taking a Java class. I am trying to put a social security number in "nnn-nn-nnnn" format where n is a digit 0-9. I don't know if it would work with the charAt method of the String class. Does anyone have any suggestions on how to implement this kind of manipulation.
It would be greatly appreciated!
Thanks,
waggypup99

You could just create a class for social security number.
e.g.
public class SSNum{
    private int _num;
    public SSNum(int number){
      _num = number;
      * take number in the form nnn-nn-nnnn
    public SSNum(String number){
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      StringBuffer numStringB = new StringBuffer(st.nextToken());
      numStringB.append(st.nextToken());
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}

Clean up output when using concat for two columns?

Probably a basic questions, but I searched this forum and google and couldn't find an answer, so here it goes...
I'm trying to concatenate two fields: first_name and last_name
I'm using the following pl/sql:
concat(a.first_name, a.last_name)But it runs the name together
smithjohn And the title shows the following
concat(a.first_name,a.last_name)And this output is going to a non-technical users, so I don't want them to freak out...
I've tried this as well
a.first_name||' '||a.last_nameAnd now the column, I get the following:
Smith John But the column heading shows
a.first_name||""||a.last_nameIs there anyway I can clean up the column heading so the end users won't be confused...?
thanks
Message was edited by:
cmmiller

For renaming the title of the column use an alias with "AS" or just put the alias after the concatenation.
Examples:
denunez@XE> select e.first_name||' '||e.last_name as Name from employees e where rownum <3
2 ;
NAME
Ellen Abel
Sundar Ande
denunez@XE> select e.first_name||' '||e.last_name Name from employees e where rownum <3
2 ;
NAME
Ellen Abel
Sundar Ande
denunez@XE> select e.first_name||' '||e.last_name "Employee Name" from employees e where rownum<3;
Employee Name
Ellen Abel
Sundar Ande

Why only +String concatation for Operator Overloading ?

Java does not support operator overloading other than the + operator for addition of two Strings or a number and a String.Why only the + operator and Strings, even when we have a concat() for addition of Strings ?
Wondering if anyone could provide me some link as to why this only this (+) operator was chosen.
Thank you for your consideration.
Edited by: amtidumpti on Apr 27, 2009 6:40 AM
Edited by: amtidumpti on Apr 27, 2009 6:40 AM

amtidumpti wrote:
stevejluke wrote:
amtidumpti wrote:
Java does not support operator overloading other than the + operator for addition of two Strings or a number and a String.Why only the + operator and Strings, even when we have a concat() for addition of Strings ? I assume the + was implemented (even with the concat() method present) for simplicity with working with Strings. Why only +? What other operators make sense as String manipulation operators? Why are they useful?We already have String,StringBuilder,StringBuffer for simplicity and manipulations of Strings or may be they were added later,but even then we have this +.Right, and you can use those methods instead of +. But String is a much-used class, has several special attributes given to it, and the + is very self-explanatory when applied to Strings.
Also would == qualify as the other operator for operator overloading in java ?== has no special meaning for Strings (or really for Objects at all). It has exactly one purpose, to compare the value of the operands provided. When the operands are primitives, it compares their values exactly as you or I would (if the primitive values are equal you get true). When the operands are reference types the value of the references are tested for equality (if they don't hold a reference to the same Object, then == returns false).
>
int iAge1=0,iAge2=0;
String sName1="Java",sName2="Rocks";
double dMark1=89.02,dMark2=92.0;
if(iAge1==iAge2)
System.out.println("HURRAH");
if(sName1==sName2)
System.out.println("HURRAH");
if(dMark1==dMark2)
System.out.println("HURRAH");Also in case of boolean :
boolean bFlag1=false,bFlag2=true;
if(bFlag1=bFlag2)
System.out.println("Value Assignment done");Here is " = " working not only as a assignment operator as well as conditional operator ?
Thanks for your consideration.

How to use multiple VCI strings for lap 1300 and 1200 (option 60) in one pool?

Hi All,
Hope to you a very happy new year,
I have two differnt LAP 1300 and 1200 in my network and I need to add theme to the WLC,
I successed to add one of theme by the option 60 in the DHCP pool at the Core SW,
So my quetion is below:
How to use multiple VCI strings for lap 1300 and 1200 (option 60) in one pool?
Thanks in Advanced,
Ahmed,

To add to Scott's post. Option 60 would be useful if you needed to put certain types of AP on specific controllers. Otherwise, no real need to use it for the most part.
Though, I do recall an issue a few years ago that some windows machines had issues getting DHCP if option 43 is being returned.
Now, on an IOS switch, you can only configure one option 60 per DHCP scope
HTH,
Steve
Please remember to rate useful posts, and mark questions as answered

Wat should be the regular expression for string MT940_UB_*.txt to be used in SFTP sender channel in PI 7.31 ??

Hi All,
What should be the regular expression for string MT940_UB_*.txt and MT940_MB_*.txt to be used as filename inSFTP sender channel in PI 7.31 ??
If any one has any idea on this please let me know.
Thanks
Neha

Hi All,
None of the file names suggested is working.
I have tried using - MT940_MB_*\.txt , MT940_MB_*.*txt , MT940*.txt
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Currently I am using generic regular expression which picks all .txt files. - ([^\s]+(\.(txt))$)
Let me know ur suggestion on this.
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Using bytes or chars for String phonetic algorithm?

Hi all. I'm working on a phonetic algorithm, much like Soundex.
Basically the program receives a String, read it either char by char or by chunks of chars, and returns its phonetic version.
The question is which method is better work on this, treating each String "letter" as a char or as a byte?
For example, let's assume one of the rules is to remove every repeated character (e.g., "jagged" becomes "jaged"). Currently this is done as follows:
public final String removeRepeated(String s){
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Would there be any improvement in this computation:public final String removeRepeated(String s){
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You may already know that getBytes() converts the string to a byte array according to the system default encoding, so the result can be different depending on which platform you're running the code on. If the encoding happens to be UTF-8, a single character can be converted to a sequence of up to four bytes. You can specify a single-byte encoding like ISO-8859-1 using the getBytes(String) method, but then you're limited to using characters that can be handled by that encoding. As long as the text contains only ASCII characters you can get away with treating bytes and characters as interchangeable, but it could turn around and bite you later.
Your purpose in using bytes is to make the program more efficient, but I don't think it's worth the effort. First, you'll be constantly converting between {color:#000080}byte{color}s and {color:#000080}char{color}s, which will wipe out much of your efficiency gain. Second, when you do comparisons and arithmetic on {color:#000080}byte{color}s, they tend to get promoted to {color:#000080}int{color}s, so you'll be constantly casting them back to {color:#000080}byte{color}s, but you have to watch for values changing as the JVM tries to preserve their signs.
In short, converting the text to bytes is not going to do anywhere near enough good to justify the extra work it entails. I recommend you leave the text in the form of {color:#000080}char{color}s and concentrate on minimizing the number of passes you make over it.

Substring for Strings, what do I use for a int variable???

Hi!
substring for Strings...
String s1 = p.substring(1,2);
but what do I use for a int variable?
int i1 = integ."???????"(1,2);
/Henrik

why, you use maths of course!!
or if you're not up to that, try this:
int x = 931;
String s = x+"";
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"buffer too small for string or missing null byte" inserting CR in excel

I have created a Crystal Report based on below stored procedure.
DELIMITER $$
DROP PROCEDURE IF EXISTS `ww_test`.`PRD_Data_sp` $$
CREATE PROCEDURE `ww_test`.`PRD_Data_sp` (in cyear int, in cmonth int, in groupby varchar(20), in Inv_type varchar(4))
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END $$
DELIMITER ;
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call ww_test.prd_data_sp({?Year},{?Month},{?GroupBy},{?InvType});
I am able to refresh the report in crystal and as well in Infoview without any problem.
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An error occurred while opening the report. The report does not exist; you have insufficient rights to open the report; or you cannot make a connection to the BusinessObjects Web Service. (LO 02010)
Failed to open report (LO 26619)
Cannot open report document
Buffer too small for string or missing null byte.
can anyone suggest where i am going wrong? Any input is appreciated.
Crystal Reports 2008
Live Office XI 3.1
BOEdge XI 3.1
Xcelsius 2008
Thanks ,
Madhavi

With the CurrentValue method
Crpt.ParamFields[3].CurrentValue := memo1.Text;
Is there another solution ?

Concat two string without 'losing' memory...

Hi,
I am using this code
public class Test{
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               //s += s;
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System.out.println("MAX MEMORY = " + Runtime.getRuntime().maxMemory() / 1048576 + "MB");
System.out.println("TOTAL MEMORY = " + Runtime.getRuntime().totalMemory() / 1048576 + "MB");
System.out.println("FREE MEMORY = " + Runtime.getRuntime().freeMemory() / 1048576 + "MB");
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System.out.println("MAX MEMORY = " + Runtime.getRuntime().maxMemory() / 1048576 + "MB");
System.out.println("TOTAL MEMORY = " + Runtime.getRuntime().totalMemory() / 1048576 + "MB");
System.out.println("FREE MEMORY = " + Runtime.getRuntime().freeMemory() / 1048576 + "MB");
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}I get on console this
8
MAX MEMORY = 508MB
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16
MAX MEMORY = 508MB
TOTAL MEMORY = 508MB
FREE MEMORY = 451MB
It took 32MB which is very much. Can I do something, and what I should do, to take less memory? It is logical if I had string of size 8 MB and to the same string I add 8 MB, to be FREE MEMORY 8 MB less then before, but not 32 MB.
Thank you.

Don't use the method concat on strings. Use a
StringBuffer or StringBuilder instead. If I instead
String s = "a"; put
StringBuffer s = new StringBuffer();
s.append("a");and instead
s = s.concat(s);put
s.append(s.toString());
FREE MEMORY becomes 472MB and 428MB, before was 483MB and 451MB.
>
Do also note that the GC executes when it needs to,
and the memory that has been allocated for the old
strings can be collected later on.And my aplication breaks :(
>
Kaj

I use Outlook for my email on the Safari web browser, and about 90% of the time when I want to attach a pdf or jpg file the email message will crash.

I use Outlook for my email on the Safari web browser, and about 90% of the time when I want to attach a pdf or jpg file it fails and about 50% of the time when I want to send a standard text massage it will also fail and the email massage crashes. The only way I can get my Outlook to work is if I switch to Firefox web browser. I would rather not switch to a new web browser if I don't have to.
It seems like what ever the problem is that its related the Safari web browser, because it works fine on the Firefox web browser.
I think its some kind of plug-in failure because it giving me a LOC ERROR:
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That's an Outlook issue. You'll probably get better responses posting on the Office for Mac forums.

Using concat for STrings

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