Pre Processors in JMeter

What are Pre Processors in JMeter?

The Pre Processor elements are used to modify the sampler requests before their processing(hence the name pre-processor).

How to add a Pre Processor-
Right Click on either of Thread Group/Logic Controller -> Hover over Add -> Hover Over Pre Processors -> Click on the required Pre Processor Element
Pre Processors in JMeter

Pre Processors provided in JMeter

BeanShell PreProcessor

The BeanShell preprocessor is used to perform some operation using beanshell scripting before a sampler request.


HTML Link Parser

The HTML Link Parser is used to extract links from HTML response fetched from server.


HTTP URL Re-writing Modifier

The HTTP URL Re-writing modifier can be added at either Thread Group level or Sampler level to fetch a specific sessionID parameter from the response of a request and then use the parameter's value on other requests.


JSR223 PreProcessor

The JSR223 preprocessor is used to perform some operation using JSR223 scripting before a sampler request.


JDBC PreProcessor

The JDBC PreProcessor is used to execute certain specified SQL queries before a sampler request processing.


RegEx User Parameters

The RegEx user parameters are used to extract HTTP parameters from certain request using a regular expression and then passed as request parameter to other sampler requests.


User Parameters

The User parameters are used to specify values for User variables used within Thread Groups.


Reference

Apache JMeter User Manual