## Gradle runtimes

Gradle is also made up of several different processes that work together to "run the build", such as the Gradle daemon and the `gradlew` command.

Each process, or "runtime", applies different constraints to the code that runs in that process.
For example, each process has different supported JVMs and a different set of services available for dependency injection.

					"toolchains-jvm-shared",
					"docs-asciidoctor-extensions-base",
					"internal-instrumentation-processor",
					"security",
					"input-tracking",
					"base-ide-plugins"
				]
			},
			{
				"parallelizationMethod":{
					"name":"TestDistribution"
				},
				"subprojects":[
					"testing-jvm",
					"worker-processes",
					"files",
					"java-language-extensions",
					"build-cache-packaging",

  
  project3["root project"]
  build2 --> project3
  
  project4["project"]
  build2 --> project4

```

### Build process state

The "build process state" holds the global state of the build process and manages all the other state.

The build process state also includes state that is tied to a particular Gradle user home directory.

import org.gradle.deployment.internal.DeploymentRegistry;
import org.gradle.internal.deployment.JavaApplicationHandle;
import org.gradle.jvm.toolchain.JavaLauncher;
import org.gradle.process.internal.JavaExecHandleBuilder;
import org.gradle.process.internal.JavaExecHandleFactory;
import org.gradle.work.DisableCachingByDefault;

import javax.inject.Inject;
import java.util.Arrays;

/**

        try {
            Process process = new ProcessBuilder().command(args).start();
            CountDownLatch latch = new CountDownLatch(2);
            ByteArrayOutputStream stdout = connectStream(process.getInputStream(), latch);
            ByteArrayOutputStream stderr = connectStream(process.getErrorStream(), latch);

            process.waitFor(1, TimeUnit.MINUTES);

                // ignore this task
                task.setEnabled(false);
                return;
            }

            task.setExecutionMode(ExecutionMode.OUT_OF_PROCESS);
            task.outputOptions(options -> {
                options.setSeparateOutputDirs(false);
                options.setBackends(singletonList("html5"));
            });

/**
 * Align with build-logic/cleanup/src/main/java/gradlebuild/cleanup/services/KillLeakingJavaProcesses.java
 */
enum class KillProcessMode {
    KILL_LEAKED_PROCESSES_FROM_PREVIOUS_BUILDS,
    KILL_PROCESSES_STARTED_BY_GRADLE,
    KILL_ALL_GRADLE_PROCESSES
}

        gradlew --> daemon
        tapi --> daemon
        
        worker["Worker process"]
        daemon --> worker

        worker2["Worker process"]
        daemon --> worker2

        worker3["Worker process"]
        daemon --> worker3
    
```

These are all Java processes. Each process has a corresponding "runtime".
All source code in Gradle is written to target one or more of these runtimes.

# ADR-0002 - Avoid using Java serialization

## Date

2012-12-01

## Context

In Gradle we often need to serialize in-memory objects for caching, or to transmit them across process barriers, etc.
Java serialization is one way to implement this, however, despite its simplicity of implementation, it has several drawbacks:

- **Performance:**
Java's built-in serialization mechanism is often slower compared to other serialization solutions.

import org.gradle.api.tasks.Internal
import org.gradle.api.tasks.Nested
import org.gradle.api.tasks.Optional
import org.gradle.api.tasks.PathSensitive
import org.gradle.api.tasks.PathSensitivity
import org.gradle.process.CommandLineArgumentProvider


abstract class AndroidStudioInstallation {
    @get:InputFiles
    @get:PathSensitive(PathSensitivity.RELATIVE)
    abstract val studioInstallLocation: DirectoryProperty
}