20 lines
589 B
Plaintext
20 lines
589 B
Plaintext
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In regular expressions the boundaries `+\^+` and `+\A+` can only match at the beginning of the input (or, in case of `+\^+` in combination with the `+MULTILINE+` flag, the beginning of the line) and `+$+`, `+\Z+` and `+\z+` only at the end.
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These patterns can be misused, by accidentally switching `+\^+` and `+$+` for example, to create a pattern that can never match.
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== Noncompliant Code Example
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----
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// This can never match because $ and ^ have been switched around
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Pattern.compile("$[a-z]*^"); // Noncompliant
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----
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== Compliant Solution
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----
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Pattern.compile("^[a-z]*$");
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----
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