Using contains/equals/== with random characters?

[David Phluphy]

Hi!

I'm wondering if there's anything I can use to check if my string array contains a word with a random character.

Something like "if(stringArray[i] == st*ing), where * can be any character from a to z ?

[Raymond Tong]

David Phluphy wrote:Hi!

I'm wondering if there's anything I can use to check if my string array contains a word with a random character.

Something like "if(stringArray[i] == st*ing), where * can be any character from a to z ?

If you compare String, you should use equals(), not ==
How about using regular expression, st[a-z]ing

[Seetharaman Venkatasamy]

David Phluphy wrote:Something like "if(stringArray[i] == st*ing), where * can be any character from a to z ?

remove 2nd index character from your input string stringArray[i] and then compare "sting".equals(refactorStringArray[i])
(or)
you can also use regular expression

  boolean b = Pattern.matches("st[a-z]ing", stringArray[i]); 

[edit]beaten by Raymond[/edit]
hth

[Soniya Ahuja]

The regex solution given by Seetha is simpler and it can be called directly on the String as well

  
if(stringArray[i].matches("st[a-zA-Z]ing"))
  

use [a-z] if you want to check for small caps or [A-Z] for caps or [a-zA-Z] if case does not matter

[David Phluphy]

Thanks for your replies so far. I've tried them all and failed gloriously each time. I should have explain the problem in more detail.

I have a method findWord(String word, String[] dictionary), which is supposed to return the index of the word in the dictionary[].

The word can either be a full word, in which case it's super simple, but it can also contain a arbitrary amount of random characters.

Let's say word1 = **z**, word2 = p*z**, word3 = piz**, word4 = piz*a and word5 = pizza.

All of these words would return 5 if dictionary[5] was "pizza"

I think this is harder than I thought at first...

[Soniya Ahuja]

Well, if this the scenario - then try exploring more of Regular Expressions

Here is a crude code that would work for the scenario you have mentioned - try refining the search algorithm and you can explore other classes as well.

   
        public static void main(String [] args) {
		String [] arr = {"**z**", "p*z**", "piz**", "piz*a", "pizza"};
		String [] dict = {"abc", "bcd", "pizza", "xyz"};
		
		for(String exp: arr) {
			exp = exp.replaceAll("\\*", "[a-zA-Z]");
			for(int i = 0 ; i < dict.length ; i++) {
				if(dict[i].matches(exp)) {
					System.out.println("Match " + dict[i] + " found at index: " + i);
				}
			}
		}
	}
 

[Soniya Ahuja]

Well, if this the scenario - then try exploring more of Regular Expressions

Here is a crude code that would work for the scenario you have mentioned - try refining the search algorithm and you can explore other classes as well.

   
        public static void main(String [] args) {
		String [] arr = {"**z**", "p*z**", "piz**", "piz*a", "pizza"};
		String [] dict = {"abc", "bcd", "pizza", "xyz"};
		
		for(String exp: arr) {
			exp = exp.replaceAll("\\*", "[a-zA-Z]");
			for(int i = 0 ; i < dict.length ; i++) {
				if(dict[i].matches(exp)) {
					System.out.println("Match " + dict[i] + " found at index: " + i);
				}
			}
		}
	}
 

Here I am assuming that each * actually stands for one random character and that random character could be between a-z or between A-Z. You can match other options as well - check java.util.regex.Pattern class' API for more details on regex patterns.

[David Phluphy]

That worked brilliantly. Good thing I didn't spend five hours trying to figure this out before posting ... oh, wait
Thanks a bunch though

[Soniya Ahuja]

Hey David,

I am glad that this worked. However, I suggest you test this for other combination and though this would work fine for smaller arrays, try checking it's performance for larger ones as well.

Good luck

[David Phluphy]

I already did.. it was absolutely horrible for larger sets
I can't figure out a way to do this fast