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  1. JDK
  2. JDK-8214245

Case insensitive matching doesn't work correctly for some character classes

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      ADDITIONAL SYSTEM INFORMATION :
      $ java -version
      openjdk version "11.0.1" 2018-10-16
      OpenJDK Runtime Environment 18.9 (build 11.0.1+13)
      OpenJDK 64-Bit Server VM 18.9 (build 11.0.1+13, mixed mode)

      A DESCRIPTION OF THE PROBLEM :
      When using the CASE_INSENSITIVE flag, the matching behavior of the POSIX character classes and a literal character class with the same set differs.

      STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
      See test program.

      EXPECTED VERSUS ACTUAL BEHAVIOR :
      EXPECTED -
      The pattern "[a-z]" should behave the same as "\\p{Lower}" which in the docs it says is US-ASCII only and the same as "[a-z]".
      ACTUAL -
      When running with the CASE_INSENSITIVE flag, "[a-z]" will match an uppercase letter, but "\\p{Lower}" will not.

      ---------- BEGIN SOURCE ----------
      // $ javac Test.java
      // $ java -ea Test
      // Exception in thread "main" java.lang.AssertionError
      // at Test.main(Test.java:8)
      import java.util.regex.Pattern;

      public class Test {
        public static void main(String[] args) {
          Pattern p1 = Pattern.compile("[a-z]", Pattern.CASE_INSENSITIVE);
          Pattern p2 = Pattern.compile("\\p{Lower}", Pattern.CASE_INSENSITIVE);
          assert(p1.matcher("A").find() == p2.matcher("A").find());
        }
      }
      ---------- END SOURCE ----------

      CUSTOMER SUBMITTED WORKAROUND :
      Avoid using POSIX character classes.

      FREQUENCY : always


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              Assignee:
              igerasim Ivan Gerasimov
              Reporter:
              webbuggrp Webbug Group
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                Updated:
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