Number-chars in string to int?

Are there any string method that converts number-chars within a string to integers?

String line = "12345";
int i = Integer.parseInt(line);
the other way aroundint i = 12345;
String line = String.valueOf(i);just a little remark.. :)

Similar Messages

What api would I use to get the number of chars in string?

What api would I use to get the number of chars in string?

Assuming that you really mean that you want the number of charaters in a String (not string), that would be documented in java.lang.String
The method is length()

Please help me with my code (has conversion from string to int)

import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;
public class Test3 extends MIDlet implements CommandListener
{   Form mForm;
    Command mCommandQuit;
    Command mCommandItem;
    TextField input,prime1,prime2,prime3,output;
    Display mDisplay;
    int i,j=0,k1,k2,p,q,b;
    //int [] current=new int [1000];
    String mstring,a="";
    String [] temp=new String [1000];
    public void startApp()
    {System.out.println("startApp");
     mForm=new Form("RSA Encryption");
     mCommandQuit=new Command("QUIT",Command.EXIT,0);
     mCommandItem=new Command("ENCRYPT",Command.ITEM,0);
     mForm.append("Enter text:\n");
     input=new TextField(null,"",100, TextField.ANY);
     mForm.append(input);
     mForm.append("Enter first prime number(p):\n");
     prime1=new TextField(null,"",100, TextField.ANY);
     mForm.append(prime1);
     mForm.append("Enter second prime number(q):\n");
     prime2=new TextField(null,"",100, TextField.ANY);
     mForm.append(prime2);
     mForm.append("Enter d:\n");
     prime3=new TextField(null,"",100, TextField.ANY);
     mForm.append(prime3);
     mForm.addCommand(mCommandQuit);
     mForm.addCommand(mCommandItem);
     mDisplay=Display.getDisplay(this);
     mDisplay.setCurrent(mForm);
     mForm.setCommandListener(this);
    public void pauseApp()
    {System.out.println("pauseApp");
    public void destroyApp(boolean unconditional)
    {System.out.println("destroyApp");
    public void commandAction(Command c, Displayable d)
    {System.out.println("commandAction");
     if(c==mCommandQuit)
        notifyDestroyed();
     else if(c==mCommandItem)
     {p = Integer.parseInt(prime1.getString());
         q = Integer.parseInt(prime2.getString());
         b = Integer.parseInt(prime3.getString());
         //breaking up of big string into ints
         mstring=input.getString();
         temp[0]="";
         for(i=1;i<mstring.length();i++)
            {if (mstring.charAt(i) == ' ')
                {j++;
                 temp[j]="";
             else
                {temp[j]=temp[j]+mstring.charAt(i);
         mForm.append("\n\nThe array is:\n");
         for(i=0;i<temp.length && temp!=null;i++)
{k1=Integer.parseInt(temp[i]); ***********************
k2=k1;
for(j=1;j<b;j++)
{k1=k1*k2;
k1=k1 %(p*q);
k2=k1 %(p*q);
a=a+new Character((char)k2).toString();
output=new TextField(null,a,100, TextField.ANY);
mForm.append(output);
}hi
this code basically takes an input of string like " 179 84 48 48 155 " (with spaces)
then it creates smaller strings in an array like "179","84","48","48","155" without the spaces
then it creates int values 179,84,48,48,155 and finally after some math functions it prints the corresponding letters.
the problem is that it is not printing the letter because of some exceptions-->java.lang.NumberFormatException .it comes in the line where i have put stars
could anybody please help me print the letters

thanks for all ur help guys, but me and my team member solved it on our own. here is the new code:
import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;
public class Test3 extends MIDlet implements CommandListener
{   Form mForm;
    Command mCommandQuit;
    Command mCommandItem;
    TextField input,prime1,prime2,prime3,output;
    Display mDisplay;
    int i,j=0,l,k1,k2,p,q,n,b;
    String mstring,a = "";
    String [] temp=new String [1000];
    public void startApp()
    {System.out.println("startApp");
     mForm=new Form("RSA Encryption");
     mCommandQuit=new Command("QUIT",Command.EXIT,0);
     mCommandItem=new Command("DECRYPT",Command.ITEM,0);
     mForm.append("Enter text:\n");
     input=new TextField(null,"",100, TextField.ANY);
     mForm.append(input);
     mForm.append("Enter first prime number(p):\n");
     prime1=new TextField(null,"",100, TextField.NUMERIC);
     mForm.append(prime1);
     mForm.append("Enter second prime number(q):\n");
     prime2=new TextField(null,"",100, TextField.NUMERIC);
     mForm.append(prime2);
     mForm.append("Enter d:\n");
     prime3=new TextField(null,"",100, TextField.NUMERIC);
     mForm.append(prime3);
     mForm.addCommand(mCommandQuit);
     mForm.addCommand(mCommandItem);
     mDisplay=Display.getDisplay(this);
     mDisplay.setCurrent(mForm);
     mForm.setCommandListener(this);
    public void pauseApp()
    {System.out.println("pauseApp");
    public void destroyApp(boolean unconditional)
    {System.out.println("destroyApp");
    public void commandAction(Command c, Displayable d)
    {System.out.println("commandAction");
     if(c==mCommandQuit)
        notifyDestroyed();
     else if(c==mCommandItem)
     {p = Integer.parseInt(prime1.getString());
         q = Integer.parseInt(prime2.getString());
         b = Integer.parseInt(prime3.getString());
         n=p*q;
         //breaking up of big string into ints
         mstring=input.getString();
         temp[0]="";
         for(i=1;i<mstring.length();i++)
            {if (mstring.charAt(i) == ' ')
                {j++;
                 temp[j]="";
             else
                {temp[j]=temp[j]+mstring.charAt(i);
         l=j;
         mForm.append("\n\nThe result is:\n");
         for(i=0;i<l;i++)
            {k1=Integer.valueOf(temp).intValue();
k2=k1;
for(j=1;j<b;j++)
{k2=k2*k1;
k2=k2 %n;
k1=k2 %n;
a=a+new Character((char)k1).toString();
output=new TextField(null,a,100, TextField.ANY);
mForm.append(output);

How to read a C structure with string and int with a java server using sock

I ve made a C agent returning some information and I want to get them with my java server. I ve settled communication with connected socket but I m only able to read strings.
I want to know how can I read strings and int with the same stream because they are sent at the same time:
C pgm sent structure :
char* chaine1;
char* chaine2;
int nb1;
int nb2;
I want to read this with my java stream I know readline methode to get the first two string but after two readline how should I do to get the two int values ?
Any idea would be a good help...
thanks.
Nicolas (France)

Does the server sent the ints in little endian or big endian format?
The class java.io.DataInputStream (with the method readInt()) can be used to read ints as binary from the stream - see if you can use it.

ASCII character/string processing and performance - char[] versus String?

Hello everyone
I am relative novice to Java, I have procedural C programming background.
I am reading many very large (many GB) comma/double-quote separated ASCII CSV text files and performing various kinds of pre-processing on them, prior to loading into the database.
I am using Java7 (the latest) and using NIO.2.
The IO performance is fine.
My question is regarding performance of using char[i] arrays versus Strings and StringBuilder classes using charAt() methods.
I read a file, one line/record at a time and then I process it. The regex is not an option (too slow and can not handle all cases I need to cover).
I noticed that accessing a single character of a given String (or StringBuilder too) class using String.charAt(i) methods is several times (5 times+?) slower than referring to a char of an array with index.
My question: is this correct observation re charAt() versus char[i] performance difference or am I doing something wrong in case of a String class?
What is the best way (performance) to process character strings inside Java if I need to process them one character at a time ?
Is there another approach that I should consider?
Many thanks in advance

>
Once I took that String.length() method out of the 'for loop' and used integer length local variable, as you have in your code, the performance is very close between array of char and String charAt() approaches.
>
You are still worrying about something that is irrevelant in the greater scheme of things.
It doesn't matter how fast the CPU processing of the data is if it is faster than you can write the data to the sink. The process is:
1. read data into memory
2. manipulate that data
3. write data to a sink (database, file, network)
The reading and writing of the data are going to be tens of thousands of times slower than any CPU you will be using. That read/write part of the process is the limiting factor of your throughput; not the CPU manipulation of step #2.
Step #2 can only go as fast as steps #1 and #3 permit.
Like I said above:
>
The best 'file to database' performance you could hope to achieve would be loading simple, 'known to be clean', record of a file into ONE table column defined, perhaps, as VARCHAR2(1000); that is, with NO processing of the record at all to determine column boundaries.
That performance would be the standard you would measure all others against and would typically be in the hundreds of thousands or millions of records per minute.
What you would find is that you can perform one heck of a lot of processing on each record without slowing that 'read and load' process down at all.
>
Regardless of the sink (DB, file, network) when you are designing data transport services you need to identify the 'slowest' parts. Those are the 'weak links' in the data chain. Once you have identified and tuned those parts the performance of any other step merely needs to be 'slightly' better to avoid becoming a bottleneck.
That CPU part for step #2 is only rarely, if every the problem. Don't even consider it for specialized tuning until you demonstrate that it is needed.
Besides, if your code is properly designed and modularized you should be able to 'plug n play' different parse and transform components after the framework is complete and in the performance test stage.
>
The only thing that is fixed is that all input files are ASCII (not Unicode) characters in range of 'space' to '~' (decimal 32-126) or common control characters like CR,LF,etc.
>
Then you could use byte arrays and byte processing to determine the record boundaries even if you then use String processing for the rest of the manipulation.
That is what my framework does. You define the character set of the file and a 'set' of allowable record delimiters as Strings in that character set. There can be multiple possible record delimiters and each one can be multi-character (e.g. you can use 'XyZ' if you want.
The delimiter set is converted to byte arrays and the file is read using RandomAccessFile and double-buffering and a multiple mark/reset functionality. The buffers are then searched for one of the delimiter byte arrays and the location of the delimiter is saved. The resulting byte array is then saved as a 'physical record'.
Those 'physical records' are then processed to create 'logical records'. The distinction is due to possible embedded record delimiters as you mentioned. One logical record might appear as two physical records if a field has an embedded record delimiter. That is resolved easily since each logical record in the file MUST have the same number of fields.
So a record with an embedded delimiter will have few fields than required meaning it needs to be combined with one, or more of the following records.
>
My files have no metadata, some are comma delimited and some comma and double quote delimited together, to protect the embedded commas inside columns.
>
I didn't mean the files themselves needed to contain metadata. I just meant that YOU need to know what metadata to use. For example you need to know that there should ultimately be 10 fields for each record. The file itself may have fewer physical fields due to TRAILING NULLCOS whereby all consecutive NULL fields at the of a record do not need to be present.
>
The number of columns in a file is variable and each line in any one file can have a different number of columns. Ragged columns.
There may be repeated null columns in any like ,,, or "","","" or any combination of the above.
There may also be spaces between delimiters.
The files may be UNIX/Linux terminated or Windows Server terminated (CR/LF or CR or LF).
>
All of those are basic requirements and none of them present any real issue or problem.
>
To make it even harder, there may be embedded LF characters inside the double quoted columns too, which need to be caught and weeded out.
>
That only makes it 'harder' in the sense that virtually NONE of the standard software available for processing delimited files take that into account. There have been some attempts (you can find them on the net) for using various 'escaping' techniques to escape those characters where they occur but none of them ever caught on and I have never found any in widespread use.
The main reason for that is that the software used to create the files to begin with isn't written to ADD the escape characters but is written on the assumption that they won't be needed.
That read/write for 'escaped' files has to be done in pairs. You need a writer that can write escapes and a matching reader to read them.
Even the latest version of Informatica and DataStage cannot export a simple one column table that contains an embedded record delimiter and read it back properly. Those tools simply have NO functionality to let you even TRY to detect that embedded delimiters exist let alone do any about it by escaping those characters. I gave up back in the '90s trying to convince the Informatica folk to add that functionality to their tool. It would be simple to do.
>
Some numeric columns will also need processing to handle currency signs and numeric formats that are not valid for the database inpu.
It does not feel like a job for RegEx (I want to be able to maintain the code and complex Regex is often 'write-only' code that a 9200bpm modem would be proud of!) and I don't think PL/SQL will be any faster or easier than Java for this sort of character based work.
>
Actually for 'validating' that a string of characters conforms (or not) to a particular format is an excellent application of regular expressions. Though, as you suggest, the actual parsing of a valid string to extract the data is not well-suited for RegEx. That is more appropriate for a custom format class that implements the proper business rules.
You are correct that PL/SQL is NOT the language to use for such string parsing. However, Oracle does support Java stored procedures so that could be done in the database. I would only recommend pursuing that approach if you were already needing to perform some substantial data validation or processing the DB to begin with.
>
I have no control over format of the incoming files, they are coming from all sorts of legacy systems, many from IBM mainframes or AS/400 series, for example. Others from Solaris and Windows.
>
Not a problem. You just need to know what the format is so you can parse it properly.
>
Some files will be small, some many GB in size.
>
Not really relevant except as it relates to the need to SINK the data at some point. The larger the amount of SOURCE data the sooner you need to SINK it to make room for the rest.
Unfortunately, the very nature of delimited data with varying record lengths and possible embedded delimiters means that you can't really chunk the file to support parallel read operations effectively.
You need to focus on designing the proper architecture to create a modular framework of readers, writers, parsers, formatters, etc. Your concern with details about String versus Array are way premature at best.
My framework has been doing what you are proposing and has been in use for over 20 years by three different major nternational clients. I have never had any issues with the level of detail you have asked about in this thread.
Throughout is limited by the performance of the SOURCE and the SINK. The processing in-between has NEVER been an issu.
A modular framework allows you to fine-tune or even replace a component at any time with just 'plug n play'. That is what Interfaces are all about. Any code you write for a parser should be based on an interface contract. That allows you to write the initial code using the simplest possible method and then later if, and ONLY if, that particular module becomes a bottlenect, replace that module with one that is more performant.
Your intital code should ONLY use standard well-established constructs until there is a demonstrated need for something else. For your use case that means String processing, not byte arrays (except for detecting record boundaries).

Detecting Number of Digits In An Int

does anyone with experience in the fundamentals of java know how to detect the number of digits in an int
i want to be able to detect the number of digits in a value recieved from a text box.
i know i can use String.length() but i want to be able to do this in the same try block that catches a NumberFormatException after using
int number = Integer.parseInt(s);
thanks for any help

i know i can use String.length() but i want to be
able to do this in the same try block that catches a
NumberFormatException after using
int number = Integer.parseInt(s);What stops you from putting it there?
Integer.toString(i).length(). Or the likes.

How to convert String to int in JSP?

Hi,
I set a session attribute in Servlet and want use it in JSP, How can I convert it to int or Integer?
the line in my code doesn't work:
int quantity=(int)session.getAttribute("vehiclequantity") ;
Thanks in advance.
Wolf
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++
<HTML>
<HEAD>
<TITLE>Using the for Statement</TITLE>
</HEAD>
<BODY>
<H1>Using the for Statement</H1>
<%=session.getAttribute("vehiclequantity") %>;
<%
int loopIndex;
int quantity=(int)session.getAttribute("vehiclequantity") ;
out.println(quantity);
for (loopIndex = 1; loopIndex <=2; loopIndex++) {
out.println("This is iteration number "
+ loopIndex + "<BR>");
%>
</BODY>
</HTML>

Learning how to read errors and understand them will help you solve your problems quicker by yourself... So lets take a look at the error and classes involved...
The error says:
"Cannor Resolve Symbol: method valueOf(java.lang.Object) in the class java.lang.Integer" and gives you line line where the error occurs: Integer quantity = Integer.valueOf(session.getAttribute("vehiclequantity"));
Now, if we look at the API for the Integer we notice that are are only two valueOf methods: valueOf(java.lang.String s) and valueOf(java.lang.String s, int radix). Not valueOf(java.lang.Object) method.
Now we look at the getAttribute(java.lang.String name) method of HttpSession we see that the method returns a java.lang.Object. Now, you know you put a java.lang.String into that attribute, but the get method returns an Object. This is because you could have put any object in there, an Integer, a String, or some other class instance. But you know it is a String, so you can cast the returned value to a String, so that you will be calling the valueOf(java.lang.String s) method of Integer with the Object returned from the HtttpSession's getAttribute(java.lang.String name) method:
Integer quantity = Integer.valueOf((String)session.getAttribute("vehiclequantity"));

Delete a char from string ?

Hi,
I want to delete a char from string. i used the following function.
String f = formulla.replace('[','');
The above function doesnt work as it tells me to put a space or some char in 2nd parameter which i dont want. i just want to delete all occurences of some specific char in a string.
Any suggestion.
Thanks alot.

u can do:
String before;
char charToReplace;
StringBuffer tempBuf = new StringBuffer(before);
for (int i=0; i<tempBuf.length(); i++)
if (tempBuf.charAt(i)==charToReplace)
tempBuf.deleteCharAt(i);
String after = tempBuf .toString(); HTH
Yonatan

Problem with String to Int conversion

Dear Friends,
Problem with String to Int conversion
I am having a column where most of the values are numeric. Only 4 values are non numeric.
I have replaces those non numeric values to numeric in order to maintain the data type.
CASE Grade.Grade WHEN 'E4' THEN '24' WHEN 'E3' THEN '23' WHEN 'E2' THEN '22' WHEN 'E1' THEN '21' ELSE Grade.Grade END
This comes the result as down
Grade
_0_
_1_
_10_
_11_
_12_
_13_
_14_
_15_
_16_
_17_
_18_
_19_
_2_
_20_
_21_
_22_
_23_
_24_
_3_
_4_
_5_
_6_
_7_
_8_
_9_
Refresh
Now I want to convert this value to numeric and do some calculation
So I changed the formula as below
cast (CASE Grade.Grade WHEN 'E4' THEN '24' WHEN 'E3' THEN '23' WHEN 'E2' THEN '22' WHEN 'E1' THEN '21' ELSE Grade.Grade END as INT)
Now I get the following error
View Display Error
_ Odbc driver returned an error (SQLExecDirectW)._
Error Details
Error Codes: OPR4ONWY:U9IM8TAC:OI2DL65P
_State: HY000. Code: 10058. [NQODBC] [SQL_STATE: HY000] [nQSError: 10058] A general error has occurred. [nQSError: 17001] Oracle Error code: 1722, message: ORA-01722: invalid number at OCI call OCIStmtFetch. [nQSError: 17012] Bulk fetch failed. (HY000)_
SQL Issued: SELECT cast ( CASE Grade.Grade WHEN 'E4' THEN '24' WHEN 'E3' THEN '23' WHEN 'E2' THEN '22' WHEN 'E1' THEN '21' ELSE Grade.Grade END as Int) saw0 FROM "Human Capital - Manpower Costing" WHERE LENGTH(CASE Grade.Grade WHEN 'E1' THEN '20' WHEN 'E2' THEN '21' WHEN 'E3' THEN '22' WHEN 'E4' THEN '23' ELSE Grade.Grade END) > 0 ORDER BY saw_0_
Refresh
Could anybody help me
Regards
Mustafa
Edited by: Musnet on Jun 29, 2010 5:42 AM
Edited by: Musnet on Jun 29, 2010 6:48 AM

Dear Kart,
This give me another hint, Yes you are right. There was one row which returns neither blank nor any value.
I have done the code like following and it works fine
Thanks again for your support
Regards
Code: cast (CASE (CASE WHEN Length(Grade.Grade)=0 THEN '--' ELSE Grade.Grade END) WHEN 'E4' THEN '24' WHEN 'E3' THEN '23' WHEN 'E2' THEN '22' WHEN 'E1' THEN '21' when '--' then '-1' ELSE Grade.Grade END as Int)

Converting chars to strings

I don't know how to get this thing to work:
public class TestGrade
public static void main(String[] args)throws GradeException
int studentID = 123423;
char grade;
String aGrade = new String();
try
   System.out.println("Student #: " + studentID);
   System.out.println("Enter a letter grade for student: ");
   grade = (char)System.in.read();
   if(grade >= 'A' && grade <= 'F' || grade >= 'f' && grade <= 'f')
    System.out.println("Student ID#: " + studentID + "Grade: " + grade);
    aGrade = grade;
   else
    throw(new GradeException(aGrade));
catch(GradeException error)
     System.out.println("Test Error: " + error.getMessage ());
}

it might help if I tell you where the error is...
   aGrade = grade; generates a rather obvious error. Incompatible types, I don't know how to convert this sucker into a string so I can feed a string into GradeException....

Detecting the first char inside string

Hi,
I search through all the String and char method but it doesn't seems to be any method to do this.
Is there anyway I can detect the first char in a String
Eg:
@#@Hello!!
Is there a method that allows me to detect H directly?

I guess you mean the first character of a particular type - excluding '@' and '#'.
morgalr wrote:
There isn't a built in function like String.firstChar() that would give you the first character of any String. You can easily make one though.There is [String.charAt(int index)|http://java.sun.com/javase/6/docs/api/java/lang/String.html#charAt(int)] which returns the character at position index. This method can't read your mind though, so charAt(0) will return the very first character regardless of whether it is "good".
In the Character class there is also a static method [isLetter(character)|http://java.sun.com/javase/6/docs/api/java/lang/Character.html#isLetter(int)] which reports "true" if the supplied character is a letter. There are lots of other methods in this class to report on the type of letter.
Perhaps you could put these ideas together: write a loop to inspect each letter in turn until you come to one that is "good".

Parsing char[] to String

I am trying to parse a char[]. Everytime I find a '\n' character I want to take the offset to that position and create a String from it. It doesn't seem to work like expected.. The strings contain parts of the array that shouldn't be there. here is some sample code that I am using. Let me know if anyone has any suggestions..
Thanks
public void parseArray( char[] buf ){
int offset = 0;
Vector v = new Vector();
for( int i=0; i < buf.length; i++ ){
if ( buf[ i ] == '\n' ){
v.add( new String( buf, offset, i ) );
offset = (i +1);
}

Try:
     public Vector parseArray(char buf[]) {
          Vector v = new Vector();
          String s = new String(buf);
          int offset =0, pos;
          do {
               pos = s.indexOf('\n',offset);
               if (pos != -1) {
                    String sub = s.substring(offset, pos);
                    v.add(sub);
                    offset = pos+1;
          } while (pos != -1 && offset < buf.length);
          if (offset < buf.length)
               v.add(s.substring(offset));
          return v;
     }

Javascript, string to int

Dear Sir:
I try to convert string to int in flash javascript:
temp="120";
temp2="140";
temp3=int ( temp );
but I got a message "int is not a function", can somebody tell me how to do this?
also, what if I want convert number back to string?
thanks a lot!

use:
temp="120";
temp2="140";
temp3=Number ( temp );
// to convert to a string, use:
var temp4:String=String(temp3);
// or
var temp5:String=temp3.toString();

Method to test if the value is a number or a string?

Hi Everybody !!!
Do you know a method that permit to test if the value is a number or a string?
Thanks !!!

What kind of value is it? Is it a String and you want to test if it holds a number or characters? If so, use toCharArray() on the String to convert it to a char array and use Character.isDigit() and/or Character.isLetter() on each of the char array elements to test it's type.

Increment a number within a string

Hi!
How can I increment a number within a string ?
This code doesn' t provide the rigth result
DATA zahl TYPE I.
DO 10 TIMES.
zahl = zahl + 1.
write:/ 'HALLO zahl'.
ENDDO.

Hello,
Change the code like this.
DATA ZAHL TYPE I.
DATA: LV_ZAHL(8),
CHAR(255).
DO 10 TIMES.
ZAHL = ZAHL + 1.
WRITE: ZAHL TO LV_ZAHL.
CONCATENATE 'HALLO' LV_ZAHL INTO CHAR.
CONDENSE CHAR NO-GAPS.
WRITE:/ CHAR."'HALLO'NO-GAP,ZAHL NO-GAP.
ENDDO.
Regards,
Vasanth

Number-chars in string to int?

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