import org.apache.maven.plugin.MojoExecution;

/**
 * Assists in firing execution events. <strong>Warning:</strong> This is an internal utility interface that is only
 * public for technical reasons, it is not part of the public API. In particular, this interface can be changed or
 * deleted without prior notice.
 *
 */
public interface ExecutionEventCatapult {

/**
 * Helps to provide backward-compatibility with plugins that use legacy components. <strong>Warning:</strong> This is an
 * internal utility interface that is only public for technical reasons, it is not part of the public API. In
 * particular, this interface can be changed or deleted without prior notice.
 *
 * @since 3.0
 */
public interface LegacySupport {

    /**

    // than wrapping cbuf in a light-weight CharSequence.
    target.append(new String(cbuf, off, len));
  }

  /*
   * Override a few functions for performance reasons to avoid creating unnecessary strings.
   */

  @Override
  public void write(int c) throws IOException {
    checkNotClosed();
    target.append((char) c);
  }

  @Override

import org.eclipse.aether.repository.RemoteRepository;
import org.eclipse.aether.repository.RepositoryPolicy;

/**
 * <strong>Warning:</strong> This is an internal utility class that is only public for technical reasons, it is not part
 * of the public API. In particular, this class can be changed or deleted without prior notice.
 *
 * @deprecated since 4.0.0, use {@code maven-api-impl} jar instead
 */
@Deprecated(since = "4.0.0")

 * <p>Use this class instead of direct calls to {@link System#nanoTime} for two reasons:
 *
 * <ul>
 *   <li>The raw {@code long} values returned by {@code nanoTime} are meaningless and unsafe to use
 *       in any other way than how {@code Stopwatch} uses them.
 *   <li>An alternative source of nanosecond ticks can be substituted, for example for testing or
 *       performance reasons, without affecting most of your code.
 * </ul>
 *

- Some base services that are available to code hosted by the runtime. This varies by runtime.
- Additional constraints. For example, the CLI client runtimes limit the libraries that are available to the code in that runtime, for performance reasons. 

Other modules and platforms define the services that they contribute to the runtime.

            DefaultRepositorySystemSession session = new DefaultRepositorySystemSession(h -> false); // no close handle

            // for technical reasons we cannot throw here, even if delegate does cancel transfer
            listener.transferInitiated(event(session, resource, TransferEvent.EventType.INITIATED));

import org.codehaus.plexus.classworlds.realm.ClassRealm;

/**
 * Caches extension class realms. <strong>Warning:</strong> This is an internal utility interface that is only public
 * for technical reasons, it is not part of the public API. In particular, this interface can be changed or deleted
 * without prior notice.
 *
 */
public interface ExtensionRealmCache {
    /**
     * A cache key.
     */

import org.apache.maven.plugin.MojoExecution;

/**
 * Assists in firing execution events. <strong>Warning:</strong> This is an internal utility class that is only public
 * for technical reasons, it is not part of the public API. In particular, this class can be changed or deleted without
 * prior notice.
 *
 */
@Named
@Singleton
public class DefaultExecutionEventCatapult implements ExecutionEventCatapult {

import java.util.Map;
import java.util.Properties;

import org.apache.maven.utils.Os;

/**
 * Assists the project builder. <strong>Warning:</strong> This is an internal utility class that is only public for
 * technical reasons, it is not part of the public API. In particular, this class can be changed or deleted without
 * prior notice.
 *
 * @since 3.0
 */
public class EnvironmentUtils {

    private static Properties envVars;