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To put this in perspective, the slowest parser handled 300,000 rows per second. I suppose it's possible for CSV parsing to be a significant part of a CPU-bound workload, but every time I've run into CSV it was ETL-type work and invariably I/O-bound. The stability and usability of a CSV library are going to be much larger factors for me than performance. Except for the time I wrote a horrible CSV-parsing regex. That actually was CPU-bound. ;) More on reddit.com

The error, as noted by u/joranstark018 , is that a request was made, by the instantiation of com.opencsv.CSVParser, to load a class called org.apache.commons.lang3.ObjectUtils. The Java Virtual Machine could not find this class (eg via JARs on the classpath). OpenCSV (scrolling down on this page you can see the direct dependencies listed) depends on Apache Commons Lang. I presume you're including dependencies like OpenCSV by manually adding JARs to the project. Normally we'd use a build tool like Maven or Gradle that manages transitive dependencies for us. Without such a tool, you're going to need to find and add each dependency (and those might have dependencies too). More on reddit.com

Jackson could be good for exposure to the Jackson APIs since they are used quite a bit if you do any spring stuff, but also work great standalone. Need some use cases if you want better answers though. More on reddit.com