Java TestNG Data Provider

In TestNG, a data provider is a method that provides test data for a test method. The test method can then use the data provided by the data provider to run multiple test cases with different input values.

Here's an example of how to use a data provider in TestNG:

import org.testng.annotations.DataProvider;
import org.testng.annotations.Test;

public class MyTest {

    @DataProvider(name = "testData")
    public Object[][] testData() {
        return new Object[][] {
            {1, 2, 3},
            {4, 5, 9},
            {-1, -2, -3}
        };
    }

    @Test(dataProvider = "testData")
    public void testAdd(int a, int b, int expected) {
        int result = a + b;
        assertEquals(result, expected);
    }
}

In this example, the testData method is a data provider that returns an array of test data. The testAdd method is a test method that takes three arguments: a, b, and expected. The testAdd method is annotated with the @Test annotation and the dataProvider attribute is set to the name of the data provider, "testData".

When the test is run, TestNG will invoke the testAdd method for each row of test data returned by the testData data provider. In this case, the testAdd method will be called three times with the following arguments:

1. a = 1, b = 2, expected = 3
2. a = 4, b = 5, expected = 9
3. a = -1, b = -2, expected = -3

You can find more information about data providers and how to use them in TestNG in the TestNG documentation.