Regular Expression in JMeter throws an error where as it is working in fine regex tester

Question

I have response from previous request. I am trying to use regular expression to get the required text. My response is given below

{
  "screen": {
    "heading": "HEADING",
    "content": {
      "lines": [
        "Scan the source CBSE. "
      ]
    },
    "prompt": {
      "default": "",
      "display_value": "HEADING",
      "masked": {
        "on": "FALSE",
        "char": "*"
      }
    }
  }
}

In the above json response i am trying to extract the word CBSE . I am using the below regular expression in regex tester - (?<=Scan the source ).*(?=. ")

But when i check the same in JMeter i am getting error and it is not saved in the variable too.

Error in JMeter: org.apache.oro.text.MalformedCachePatternException: Invalid expression: (?<=Scan the source ).*(?=. ") Sequence (?<...) not recognized

Does this answer your question? [Regex: Extract string between two strings. No apparent delimitors](https://stackoverflow.com/questions/40795568/regex-extract-string-between-two-strings-no-apparent-delimitors) — Ryszard Czech, Nov 18 '21 at 22:28

score -1 · Accepted Answer · answered Nov 18 '21 at 11:34

I don't think your regex is valid for Jakarta ORO syntax, try something more simple like:

"Scan the source\s*(.+?)\. "

Also be aware that JMeter provides Boundary Extractor so it's sufficient to just supply "left" and "right" boundaries and JMeter will get everything in-between:

Moreover this approach consumes less resources, see The Boundary Extractor vs. the Regular Expression Extractor in JMeter article for more information.

Regular Expression in JMeter throws an error where as it is working in fine regex tester

1 Answers1