TestNG parallel Execution with DataProvider

Question

I have a single test which receives data from data provider. I would like this test to run in parallel with different values from data provider .

I tried an approach like :

public class IndependentTest
{
@Test(dataProvider = "dp1" ,threadPoolSize=3,invocationCount=1)

public void testMethod(int number)
{
    Long id = Thread.currentThread().getId();
    System.out.println("HELLO :  " + id);
}


@DataProvider(name = "dp1",parallel=true)
public Object[][] dp1() {
  return new Object[][] {
      new Object[] { 1 },
      new Object[] { 2 },
      new Object[] { 3 },
      new Object[] { 4 },
      new Object[] { 5 },
      new Object[] { 6 },
      new Object[] { 7 },
      new Object[] { 8 }

  };
}

}

The output i received is :

HELLO : 10

HELLO : 12

HELLO : 17

HELLO : 11

HELLO : 16

HELLO : 14

HELLO : 13

HELLO : 15

Spawned 10 threads while i specified 5 in the thread pool size . Could you please tell what has to be added to the above snippet to control the data provider thread pool size .

Answer 1

Try to set the thread pool in following way:

@BeforeClass
public void setupClassName(ITestContext context) {
    context.getCurrentXmlTest().getSuite().setDataProviderThreadCount(5);
    context.getCurrentXmlTest().getSuite().setPreserveOrder(false);
}

Answer 2

You need to use dataproviderthreadcount. The threadpoolsize and invocationcount values are not required. See details here.

Answer 3

Currently only one thread is getting used as you have define invocationCount as 1, if you change it to 3 then three workers thread will get used.

invocationCount :- The number of times this method should be invoked.

threadPoolSize :- The size of the thread pool for this method. The method will be invoked from multiple threads as specified by invocationCount. Note: this attribute is ignored if invocationCount is not specified.

Also,

You can also specify that a @Test method should be invoked from different threads. You can use the attribute threadPoolSize to achieve this result:

@Test(threadPoolSize = 3, invocationCount = 10,  timeOut = 10000)
public void testServer() {

In this example, the function testServer will be invoked ten times from three different threads. Additionally, a time-out of ten seconds guarantees that none of the threads will block on this thread forever.

More info can be found here

Answer 4

In testng.xml you can set thread count for the dataprovider via data-provider-thread-count="3"

<suite name="Manage" data-provider-thread-count="3" >
    <test name="Manage data tests">
        <classes>
            <class name="uk.example.ExampleTest"></class>
        </classes>
    </test>
</suite>