Java's String Tokenizer

[red_evolve]

Hi. I have just been introduced to string tokenizer in one of the java lessons. It can remove characters from an array of strings. So, I am wondering if it could remove a string from an array of string. For example: "the fish was eaten by the cat". I'd like to remove "the" from this array of string, resulting to: "fish was eaten by cat", without getting all t's, h's and e's from the array of string. Is this possible? :) :roll:

[sooim3]

AFAIK, the StringTokenizer does not in itself remove characters; it breaks up a string in tokens at given delimeters. If StringTokenizer is constructed like this:

StringTokenizer st=new StringTokenizer("the fish was eaten by the cat");

...the default delimeters are:
- space character
- the tab character
- newline character
- carriage-return character
- form-feed character

If you want to remove the 'the' from your string, then the above construction would work, since the sentence consists of space characters that delimits each word.

And one way to remove the 'the' from the string, is using a simple little loop to check if the word, a token, is equals to 'the' or not.

Like such:

Create a new output string
Construct the StringTokenizer with the string that is to be parsed ("the fish was eaten by the cat")

Check each word with a loop:
While there is more tokens
Create a new temporary string with the nextToken()
If the temporary string does not equals 'the'
Add temporary string to the output string
(else do nothing)
print out the outputstring

...That should result in: "fish was eaten by cat"

Hope this is of any help,
/Soo-Im

[samaru]

The String tokenizer doesn't have a method to remove tokens. If you have a string like "the fish was eaten by the cat" rather than going through the overhead of creating more objects, just use the native method "replace" or "replaceall" that comes with the String object. You can replace the "the" with an empty string and thus take it out.

[red_evolve]

Thank you so much...So, here I am, trying with those suggestions given...

class extra{
     public static void main(String[] args){
          String output = "";
          for&#40;int i=0; i<args.length; i++&#41;&#123;
                if&#40;args&#91;i&#93; != "the"&#41;
                       output+= args&#91;i&#93;;
          &#125;
          System.out.println&#40;"Results&#58; "+output&#41;;
          System.exit&#40;0&#41;;
     &#125;
&#125;

I thought the above might work, without using StringTokenizer....but, hmph...it turned out to print the whole thing! :(
I have tried using sooim3's suggestion, but it didnt work as well, maybe my code is wrong...
I'm not sure...

[sooim3]

Uhm, my suggestion wasn't at all as good as the one that followed... you could try this:

public class TokenTest {

public static void main(String[] args) {
System.out.println("the fish was eaten by the cat".replaceAll("the", ""));
}
}

/Soo-Im

[red_evolve]

Cool~
Thanks...hehe...guess I've learned something new here. Btw, this means that replaceAll is a method in java.lang.String?

[samaru]

Yes. Check out the Java API docs for String:
http://java.sun.com/j2se/1.4.2/docs/api/java/lang/String.html

The whole J2SE API:
http://java.sun.com/j2se/1.4.2/docs/api/

[lohengrin332]

This code will work if you use

!args[i].equals("the")

instead of

args[i] != "the"

. The latter doesn't work because you end up comparing the location in memory rather than the contents of the memory, like when you compare pointers in C without dereferencing them. Sometimes it will work, but usually it will not.

class extra{
     public static void main(String[] args){
          String output = "";
          for&#40;int i=0; i<args.length; i++&#41;&#123;
                if&#40;args&#91;i&#93; != "the"&#41;
                       output+= args&#91;i&#93;;
          &#125;
          System.out.println&#40;"Results&#58; "+output&#41;;
          System.exit&#40;0&#41;;
     &#125;
&#125;

[red_evolve]

wow! thanks so much! ;)

[mackverick]

Well i wasn't sure where to post my question but since you guys are talking about tokens and all that, i have a question...

this is my first Java course and i am having troubles doing one of the assignments... well i am suppose to read a file containing grades of students...here is an example

034-23-8901 45 78 85 34
342-67-1231 98 45 67 45
452-57-2351 49 78 61 52

the first 9 digits are the social security of the student and the other numbers are the grades. well i am suppose to open this file ( it is named Grades.txt) somehow i am suppose to read the grades and find the average if the student has an average of 90 or above he will be excluded from the final and then my program has to write an outFile named Exemption... it seems very easy but i just can't get it to work...

My question is do i have to use the tokenizer to separate the numbers... if it is possible how can i do it?

Please i will appreciate any help...

[RBDurgin@Gmail]

It is printing out the whole thing because args[i] != "the" is not comparing the string contents, it is comparing the string objects themselves (by comparing thier hash codes).

The comparison you want is:
if(!args[i].equals("the"))
output+= args[i];

An easier method of replacement, as noted above would be:
output = args.replaceAll("the","")

Thank you so much...So, here I am, trying with those suggestions given...

class extra{
     public static void main(String[] args){
          String output = "";
          for(int i=0; i<args.length; i++){
                if(args[i] != "the")
                       output+= args[i];
          }
          System.out.println("Results: "+output);
          System.exit(0);
     }
}

I thought the above might work, without using StringTokenizer....but, hmph...it turned out to print the whole thing! :( I have tried using sooim3's suggestion, but it didnt work as well, maybe my code is wrong... I'm not sure...

[lonely gurl]

guys, help m plz.. i need a java code that separate a number from words..

[javaAddict]

guys, help m plz.. i need a java code that separate a number from words..

Be more specific, start a new thread and show what you have done so far

[skylover]

I understand that tokenizer can be used to remove trailing or beginning of a word.

I would like to traim away the whitespace in between.
Example would be

"Software Development Example twoWhiteSpace"

I would like the above line to be like this :

"Software Development Example oneWhiteSpace"

Is it possible with tokenizer or is there any workable way around?