WHAT IS JMETER? JMeter was first developed byStefano Mazzocchi of the Apache Software Foundation, designed totest and measure the performance and functional behavior of client/server applications, such as web applications or FTP applications.
A TYPICAL TEST PLAN WILL CONSISTOF ONE OR MORE : Thread Group: Each thread group simulates a single user. Listeners: Provide access to the information gathered by JMeter about the test cases while JMeter runs. Since there are several listeners that come with JMeter it’s important to say that all of them save the same data, the only difference is in the way the data is presented on the screen. Sampler: Tell JMeter to send a request to a server. Logic Controllers: Determine the order in which samplers are processed.
To understand the effect of Logic Controllers on a test plan, consider thefollowing test tree: Test Plan Thread Group Once Only Controller Login Request (an HTTP Request ) Load Search Page (HTTP Sampler) Interleave Controller Search "A" (HTTP Sampler) Search "B" (HTTP Sampler) HTTP default request (Configuration Element) HTTP default request (Configuration Element) Cookie Manager (Configuration Element) The first thing about this test is that the login request will be executed only the first time through. Subsequent iterations will skip it. This is due to the effects of the Once Only Controller .
Timers: Allow JMeter to delay between each request that a thread makes. Assertions: Allow you to test that your application is returning the results you expect it to. Configuration Elements: A configuration element works closely with a Sampler. Although it does not send requests (except for HTTP Proxy Server ), it can add to or modify requests. Pre-processor Elements: A Pre-Processor executes some action prior to a Sampler Request being made. Post-Processor Elements: A Post-Processor executes some action after a Sampler Request has been madeA Post- Processor executes some action after a Sampler Request has been made.
Once JMeter runs, you will see twoelements, Test Plan and WorkBench
Test Plan sample consisting of more than oneThread Group and multiple elements in each Thread Group
Test Plan sample having a single Thread Group incorporating multiple elements
Thread Group sample with details is shown below
The Response Assertion element shown in the following figure predefines the pattern matching conditions
The Assertion Results element shown in following figure will capture these predefined patterns in the data or page response and display them for further analysis