I think these logs are generated by some custom Request Filter/Interceptor. You should give a try to Tomcat access logs if you are using Tomcat Server, there are flexible and easy to parse.

For ref check: https://tomcat.apache.org/tomcat-9.0-doc/config/valve.html#Access_Logging

Furthermore you can check this repo for tomcat access log parsing: https://github.com/YasinVighio/Tomcat-Log-Analyzer

If you are sticking with custom logging then I suggest you to identify pattern of logs

• Each entry is of 5 lines, you may use line counter while reading the file.

• First line contains Timestamp, Thread name, Logging Level, Class Name - Rest Request (Some sort of constant), These can be transformed into DTO fields if you split 1st line with Space Delimiter

• Second, third and fourth can be split with first '=' found

• Fifth line has also same pattern as of 1st, it can be transformed into DTO fields the same way.