appendToDocList is a Java service. A doc list is simply an array of IData objects. You’re not going to be faster with your own Java service if you still use an array.
And if you don’t use arrays, and instead use something like a hashmap or other collection classe, then you’ll need to adjust your services to convert that to a doc list when you’re done building it up (I’ve done this in the past and it’s fairly easy).
Before writing your own services, test to see if appendToDocList will perform satisfactorily in your environment for your integration.
I do not know if using a regex in the loop will have a significant impact on performance. Test it to find out. Intuitively it seems that it would be slower than other types of checks but, 1) it might not be, and; 2) the slow-down may not be enough to matter. Test first, then tune.
#webMethods#Integration-Server-and-ESB#Flow-and-Java-services