CODEWITHSUNDEEP
java
JungJoo
JungJoo

Reputation: 171

pattern method matches returns false

I have 

String b = "aasf/sdf/dfd/*";
Pattern.matches("[^ ]", b);

I keep getting returned false in Patter.matches();

Since it matches regex, all characters beside space character, shouldn't it return true?

Upvotes: 0

Views: 631

Answers (4)

Anirudha
Anirudha

Reputation: 32797

Pattern.matches would try to match the pattern exactly..

So it would return true only if you have a single non space character as input.

Its like using \A[^ ]\z

where \A is the beginning of input and \z is end of input..

If you want to check for strings that doesn't contain space you can use

input.matches("[^ ]*");

Upvotes: 1

Nir Alfasi
Nir Alfasi

Reputation: 53525

As anirudh suggested, Pattern matchers are used differently (see the other answers for examples), I believe that what you were trying to do is the following:

    String b = "aasf/sdf/dfd/*";
    System.out.println("b.matches(\"[^ ]\") = " + b.matches("[^ ]"));

OUTPUT

b.matches("[^ ]") = false

Upvotes: 1

Hari Menon
Hari Menon

Reputation: 35405

Pattern.matches() returns true only if the entire string matches the regex. What you want to do is to see if the pattern occurs anywhere in the String. You need to use Matcher.find() for that.

e.g,

    String testStr = "aasf/sdf/dfd/*";
    Pattern patt = Pattern.compile("[^ ]");
    Matcher m = patt.matcher(testStr);
    while (m.find()) {
        System.out.println(m.group(0));
    }

This will print all matches. If you just need to know if a pattern is found, just check if m.find() is true.

Upvotes: 0

Archer
Archer

Reputation: 5147

No, coz you try to match whole string to NON-SPACE character.

String b = "aasf/sdf/dfd/*";
Pattern.matches("[^ ]*", b);

This one will return true

Upvotes: 1

Related Questions