func etcdErrToErr(err error, etcdEndpoints []string) error {
	if err == nil {
		return nil
	}
	switch err {
	case context.DeadlineExceeded:
		return fmt.Errorf("%w %s", errEtcdUnreachable, etcdEndpoints)
	default:
		return fmt.Errorf("unexpected error %w from etcd, please check your endpoints %s", err, etcdEndpoints)
	}
}

func saveKeyEtcdWithTTL(ctx context.Context, client *etcd.Client, key string, data []byte, ttl int64) error {

Boolean flag = BooleanConversionUtil.toBoolean("true");        // Returns true
Date date = DateConversionUtil.toDate("2023-12-25", "yyyy-MM-dd");

// Primitive conversions with default values
int primitiveInt = IntegerConversionUtil.toPrimitiveInt(value, "0");  // Default to 0 if null
```

### Collection Utilities with Java 21 Support
```java
import org.codelibs.core.collection.CollectionsUtil;
import java.util.SequencedCollection;

import jakarta.annotation.Resource;

/**
 * Admin action for Request Header management.
 *
 */
public class AdminReqheaderAction extends FessAdminAction {

    /**
     * Default constructor.
     */
    public AdminReqheaderAction() {
        super();
    }

    /** Role name for admin request header operations */
    public static final String ROLE = "admin-reqheader";

    /** Base directory for command execution. */
    protected File baseDir;

    /** Timer for managing process destruction. */
    private Timer destoryTimer;

    /**
     * Default constructor for CommandGenerator.
     */
    public CommandGenerator() {
        super();
    }

    /**
     * Initializes the command generator after construction.
     */
    @PostConstruct

     * during artifact resolution, {@link #VALIDATION_LEVEL_MINIMAL} should be used to account for models of poor
     * quality. By default, models are validated in strict mode.
     *
     * @param validationLevel The level of validation to perform on processed models.
     * @return This request, never {@code null}.
     */

        try {
            MavenSession clone = (MavenSession) super.clone();
            // the default must become the current project of the thread that clones this
            MavenProject current = getCurrentProject();
            // we replace the thread local of the clone to prevent write through and enforce the new default value
            clone.currentProject = ThreadLocal.withInitial(() -> current);
            return clone;

### Default Container Annotation

Pod with multiple containers can use `kubectl.kubernetes.io/default-container` annotation to have a container preselected for kubectl commands. More can be read in [KEP-2227](https://github.com/kubernetes/enhancements/blob/master/keps/sig-cli/2227-kubectl-default-container/README.md).

### Immutable Secrets and ConfigMaps

# Case 15: Unicode and special characters in user-agent
User-agent: Bot™
Disallow: /trademark/

User-agent: Bot®
Disallow: /registered/

# Case 16: Multiple wildcards user agent
User-agent: *
Disallow: /default/

# Case 17: Empty file handling (just comments and whitespace after this)

     * as the specified wildcard and attributes are passed to the server for
     * filtering there (although attributes are largely ignored by servers
     * they are filtered locally by the default accept method).
     *
     * @param wildcard the wildcard pattern for matching file names (e.g., "*.txt")
     * @param attributes the DOS file attributes to match (e.g., ATTR_DIRECTORY)
     */

        assertArrayEquals(mic, roundTrip.getMechanismListMIC(), "mic should roundtrip");
    }

    @Test
    @DisplayName("default constructor – unspecified result")
    void testDefaultResult() {
        NegTokenTarg nt = new NegTokenTarg();
        assertEquals(NegTokenTarg.UNSPECIFIED_RESULT, nt.getResult(), "new object should have UNSPECIFIED_RESULT");