regex - regular expression in java inside an if block -

regex - regular expression in java inside an if block -

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reference - regex mean? 1 reply

i can see below regular look in code ...

if (amount.matches("[-+]?[0-9]*\\.?[0-9]+")) homecoming true;

now query regular look represent amount should numeric , validation check

your regex works :

"[-+]?[0-9]*\\.?[0-9]+" [-+]? --> either `+` or `-` or nothing. followed [0-9]* --> number of digits (* implies greedy check). followed `\\.?` --> 0 or 1 `.` (matched literally. ). followed [0-9]+ --> 1 or more digits

demo here

java regex