* KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
package org.apache.maven.toolchain;

import org.apache.maven.execution.MavenSession;

/**
 * Component for use by the <code>maven-toolchains-plugin</code> only.
 * It provides API: <ol>
 * <li>to retrieve every toolchains available in user settings,</li>

 */
package org.codelibs.fess.exception;

/**
 * Exception thrown during SSO (Single Sign-On) processing operations.
 *
 * This exception is used to indicate errors that occur during the execution
 * of SSO authentication and authorization processes. It extends FessSystemException
 * to provide consistent error handling within the Fess system for SSO-related

    private final List<ScoreBooster> scoreBoosterList = new ArrayList<>();

    /**
     * Executes all score boosters.
     * @return The result of the execution.
     */
    public String execute() {
        final StringBuilder resultBuf = new StringBuilder();
        scoreBoosterList.forEach(b -> {
            try {
                final long count = b.process();

 * which collects necessary information for Build Scan.
 */
fun <T : AbstractBuildScanInfoCollectingService> Project.registerBuildScanInfoCollectingService(
    /* the implementation class to collect information from task execution result */
    klass: Class<T>,
    /* which tasks we need to monitor? For example, cache-miss-monitor monitors `AbstractCompile` tasks */
    taskFilter: (Task) -> Boolean,

import java.nio.file.Files;

import org.apache.maven.artifact.AbstractArtifactComponentTestCase;
import org.apache.maven.artifact.Artifact;
import org.apache.maven.artifact.repository.ArtifactRepository;
import org.apache.maven.execution.MavenSession;
import org.apache.maven.session.scope.internal.SessionScope;
import org.junit.jupiter.api.Test;

import static org.codehaus.plexus.testing.PlexusExtension.getBasedir;

 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
package org.apache.maven.execution;

import java.util.Collections;
import java.util.IdentityHashMap;
import java.util.List;
import java.util.Map;
import java.util.concurrent.CopyOnWriteArrayList;

└── fess-crawler-opensearch/  # OpenSearch backend
```

### Key Components

#### Core Engine
- **Crawler**: Main orchestrator managing crawl execution
- **CrawlerContext**: Execution context and configuration
- **CrawlerThread**: Individual crawler thread implementation

#### Client Architecture
- **HcHttpClient**: HTTP/HTTPS client using Apache HttpComponents

import static org.mockito.Mockito.mock;
import static org.mockito.Mockito.verify;
import static org.mockito.Mockito.when;

/**
 * Unit tests for the {@link StrategyOrchestrator} class.
 * Tests strategy execution coordination and result aggregation.
 */
@DisplayName("StrategyOrchestrator")
class StrategyOrchestratorTest {

    private StrategyOrchestrator orchestrator;
    private List<UpgradeStrategy> mockStrategies;

- plugin artifact retrieval problem
- plugin dependency metadata missing
- plugin dependency metadata retrieval problem
- plugin configuration problem
- plugin execution failure due to something that is known to possibly go wrong (like compilation failure)
- plugin execution error due to something that is not expected to go wrong (the compiler executable missing)

import java.util.Collection;

import org.apache.maven.api.Event;
import org.apache.maven.api.EventType;
import org.apache.maven.api.Listener;
import org.apache.maven.eventspy.EventSpy;
import org.apache.maven.execution.ExecutionEvent;

/**
 * Bridges between Maven3 events and Maven4 events.
 */
@Named
@Singleton
public class EventSpyImpl implements EventSpy {
    @Override