testng-parallel

# TestNG Parallel Execution

Master TestNG parallel test execution including thread pool configuration, suite-level parallelism, method-level parallelism, and thread safety patterns. This skill covers techniques for maximizing test throughput while maintaining test reliability.

## Overview

TestNG supports parallel execution at multiple levels: suite, test, class, and method. Proper parallel configuration can significantly reduce test execution time, but requires careful consideration of thread safety and resource management.

## Parallel Execution Modes

### Suite-Level Parallelism

Run multiple `<test>` tags in parallel:

```xml
<!DOCTYPE suite SYSTEM "https://testng.org/testng-1.0.dtd">
<suite name="Parallel Suite" parallel="tests" thread-count="3">

    <test name="Chrome Tests">
        <classes>
            <class name="com.example.tests.BrowserTest"/>
        </classes>
    </test>

    <test name="Firefox Tests">
        <classes>
            <class name="com.example.tests.BrowserTest"/>
        </classes>
    </test>

    <test name="Safari Tests">
        <classes>
            <class name="com.example.tests.BrowserTest"/>
        </classes>
    </test>

</suite>
```

### Class-Level Parallelism

Run test classes in parallel:

```xml
<!DOCTYPE suite SYSTEM "https://testng.org/testng-1.0.dtd">
<suite name="Parallel Classes" parallel="classes" thread-count="4">

    <test name="All Tests">
        <classes>
            <class name="com.example.tests.UserServiceTest"/>
            <class name="com.example.tests.ProductServiceTest"/>
            <class name="com.example.tests.OrderServiceTest"/>
            <class name="com.example.tests.PaymentServiceTest"/>
        </classes>
    </test>

</suite>
```

### Method-Level Parallelism

Run test methods in parallel:

```xml
<!DOCTYPE suite SYSTEM "https://testng.org/testng-1.0.dtd">
<suite name="Parallel Methods" parallel="methods" thread-count="5">

    <test name="Service Tests">
        <classes>
            <