/usr/share/doc/libregexp-java/api/org/apache/regexp/class-use/ is in libregexp-java-doc 1.5-3.
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/usr/share/doc/libregexp-java/api/org/apache/regexp/class-use/CharacterArrayCharacterIterator.html
/usr/share/doc/libregexp-java/api/org/apache/regexp/class-use/CharacterIterator.html
/usr/share/doc/libregexp-java/api/org/apache/regexp/class-use/RE.html
/usr/share/doc/libregexp-java/api/org/apache/regexp/class-use/RECompiler.RERange.html
/usr/share/doc/libregexp-java/api/org/apache/regexp/class-use/RECompiler.html
/usr/share/doc/libregexp-java/api/org/apache/regexp/class-use/REDebugCompiler.html
/usr/share/doc/libregexp-java/api/org/apache/regexp/class-use/REDemo.html
/usr/share/doc/libregexp-java/api/org/apache/regexp/class-use/REProgram.html
/usr/share/doc/libregexp-java/api/org/apache/regexp/class-use/RESyntaxException.html
/usr/share/doc/libregexp-java/api/org/apache/regexp/class-use/RETest.html
/usr/share/doc/libregexp-java/api/org/apache/regexp/class-use/RETestCase.html
/usr/share/doc/libregexp-java/api/org/apache/regexp/class-use/REUtil.html
/usr/share/doc/libregexp-java/api/org/apache/regexp/class-use/ReaderCharacterIterator.html
/usr/share/doc/libregexp-java/api/org/apache/regexp/class-use/StreamCharacterIterator.html
/usr/share/doc/libregexp-java/api/org/apache/regexp/class-use/StringCharacterIterator.html
/usr/share/doc/libregexp-java/api/org/apache/regexp/class-use/recompile.html