regex: java.util.regex companion code (groups, lookarounds, replaceAll lambdas, ReDoS and timeouts)

Co-Authored-By: Claude Sonnet 5.5 <[email protected]> Claude-Session: https://claude.ai/code/session_01KqJyCidz3ZgRyHABv2GVJh
2026-09-30 19:00:39 +00:00
parent bfa7f97432
commit b31c6716a3
22 changed files with 647 additions and 0 deletions
@@ -0,0 +1,28 @@
+cap per run: 2000 ms; input = n letters 'a' followed by '!' (no match possible)
+
+pattern (a+)+b
+  n=20     0 ms  matches=false
+  n=36     0 ms  matches=false
+  n=500    1 ms  matches=false
+  n=1000   23 ms  matches=false
+  n=2000   63 ms  matches=false
+  n=4000   161 ms  matches=false
+
+pattern (a+)+\1?b
+  n=20     27 ms  matches=false
+  n=24     690 ms  matches=false
+  n=26     ABORTED after 2036 ms (cap)
+
+pattern (?:(?:a+)+)+b
+  n=16     3 ms  matches=false
+  n=18     13 ms  matches=false
+  n=20     101 ms  matches=false
+  n=22     896 ms  matches=false
+  n=24     ABORTED after 2000 ms (cap)
+
+pattern a*a*a*a*b
+  n=50     2 ms  matches=false
+  n=100    69 ms  matches=false
+  n=150    285 ms  matches=false
+  n=200    824 ms  matches=false
+