July 2017
Intermediate to advanced
158 pages
3h 41m
English
Content preview from Java 9 Regular Expressions
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Use lazy quantifiers strategically instead of greedy quantifiers that cause excessive backtracking
Suppose we need to match an input that contains three complete words, start, middle, and end, separated by non-whitespace characters.
Consider using the following pattern with a lazy quantifier:
\bstart\b\S+?\bmiddle\b\S+?\bend\b
Instead of using the following pattern, our match will be faster if we use the preceding pattern:
\bstart\b\S+\bmiddle\b\S+\bend\b
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