}

    /**
     * Sets the exception that occurred while accessing the content.
     *
     * @param e the exception to set.
     */
    public void setContentException(final Exception e) {
        contentException = e;
    }

    /**
     * Gets the exception that occurred while accessing the content, if any.
     *
     * @return the exception, or null if no exception occurred.

 *
 * <p>This interface is meant to be used as the type of a parameter to graph algorithms (such as
 * topological sort) that only need a way of accessing the predecessors of a node in a graph.
 *
 * <h3>Usage</h3>
 *
 * Given an algorithm, for example:
 *
 * {@snippet :
 * public <N> someGraphAlgorithm(N startNode, PredecessorsFunction<N> predecessorsFunction);

 *
 * <p>This interface is meant to be used as the type of a parameter to graph algorithms (such as
 * breadth first traversal) that only need a way of accessing the successors of a node in a graph.
 *
 * <h3>Usage</h3>
 *
 * Given an algorithm, for example:
 *
 * {@snippet :
 * public <N> someGraphAlgorithm(N startNode, SuccessorsFunction<N> successorsFunction);
 * }

    @Test
    public void test_clearCache() {
        // Test that clearCache doesn't throw exception
        popularWordHelper.clearCache();

        // Verify cache is cleared (we can't directly test this without accessing the cache)
        // But we can test that it doesn't throw exceptions
        assertTrue(true);
    }

    @Test
    public void test_init_configuration() {

  // By preference, we will use the Thread constructor that has an `inheritThreadLocals` parameter.
  // But before Java 9, our only way not to inherit ThreadLocals is to zap them after the thread
  // is created, by accessing a private field.
  private static final @Nullable Constructor<Thread> bigThreadConstructor =
      getBigThreadConstructor();

  private static final @Nullable Field inheritableThreadLocals =

 */
public class ThumbnailGenerator {

    private static final Logger logger = LogManager.getLogger(ThumbnailGenerator.class);

    /**
     * OpenSearch client for accessing indexed documents.
     */
    @Resource
    public SearchEngineClient searchEngineClient;

    /**
     * Default constructor for ThumbnailGenerator.
     */
    public ThumbnailGenerator() {

        }
    }

    // Test concurrent access
    @Test
    public void test_get_concurrentAccess() throws InterruptedException {
        // Create multiple threads accessing the same property
        final String testKey = "domain.title";
        final int threadCount = 10;
        final Thread[] threads = new Thread[threadCount];
        final String[] results = new String[threadCount];

  // By preference, we will use the Thread constructor that has an `inheritThreadLocals` parameter.
  // But before Java 9, our only way not to inherit ThreadLocals is to zap them after the thread
  // is created, by accessing a private field.
  private static final @Nullable Constructor<Thread> bigThreadConstructor =
      getBigThreadConstructor();

  private static final @Nullable Field inheritableThreadLocals =

    @Resource
    protected QueryHelper queryHelper;

    /** Helper for executing search operations. */
    @Resource
    protected SearchHelper searchHelper;

    /** HTTP servlet request for accessing request parameters. */
    @Resource
    protected HttpServletRequest request;

    /** Current form reference for rendering extra fields on the edit page. */
    private CreateForm currentForm;

              }

              System.out.println(responseBody.string());
            }
          }
        });
      }
    ```

### Accessing Headers ([.kt][AccessHeadersKotlin], [.java][AccessHeadersJava])