//                                                                          Validation
    //                                                                          ==========
    @SuppressWarnings("unchecked")
    /**
     * Creates a validator instance for form validation.
     * This method uses the system helper to create a validator with Fess-specific messages.
     *
     * @return a new action validator instance

public class UnmodifiableCollectionTests {

  public static void assertMapEntryIsUnmodifiable(Entry<?, ?> entry) {
    try {
      // fine because the call is going to fail without modifying the entry
      @SuppressWarnings("unchecked")
      Entry<?, @Nullable Object> nullableValueEntry = (Entry<?, @Nullable Object>) entry;
      nullableValueEntry.setValue(null);
      fail("setValue on unmodifiable Map.Entry succeeded");

    }

    /**
     * Get values from array index.
     * @param index Index
     * @param type Type
     * @param key Key
     * @return Values
     */
    @SuppressWarnings("unchecked")
    protected Map<String, Object>[] getFromArrayIndex(final String index, final String type, final String key) {
        final String actualIndex = index + "." + type.toLowerCase(Locale.ENGLISH);
        try {

        this.isDataFromNodeStatus = true;
    }

    /**
     * {@inheritDoc}
     *
     * @see jcifs.Address#unwrap(java.lang.Class)
     */
    @SuppressWarnings("unchecked")
    @Override
    public <T extends Address> T unwrap(final Class<T> type) {
        if (type.isAssignableFrom(this.getClass())) {
            return (T) this;
        }
        return null;
    }

import org.junit.jupiter.api.Test;

import static org.junit.jupiter.api.Assertions.assertEquals;
import static org.junit.jupiter.api.Assertions.assertTrue;

/**
 * Test ComparableVersion.
 */
@SuppressWarnings("unchecked")
class ComparableVersionTest {
    private ComparableVersion newComparable(String version) {
        ComparableVersion ret = new ComparableVersion(version);
        String canonical = ret.getCanonical();

            final Map<String, Object> defaultSettings = defaultSettings();
            initialSettings.forEach((key, value) -> {
                if (value instanceof Collection) {
                    @SuppressWarnings("unchecked")
                    final Collection<Object> collection = (Collection<Object>) value;
                    collection.forEach(element -> arraySettings.add(new Tuple<>(key, element)));

These custom validators are for things that can be checked with **only** the **same data** provided in the request.

///

### Understand that Code { #understand-that-code }

    void sendWithRequestVarargsDelegates() throws Exception {
        // Verifies Request<T> overload forwards to the varargs form with a null response
        @SuppressWarnings("unchecked")
        Request<CommonServerMessageBlockResponse> req = mock(Request.class);
        CommonServerMessageBlockResponse resp = mock(CommonServerMessageBlockResponse.class);

        // Stub tree send for varargs

   * This does perform a little more work than necessary, so another option is to insert an
   * unchecked cast at some later point:
   *
   * {@snippet :
   * @SuppressWarnings("unchecked") // safe because of ::isInstance check
   * ImmutableList<NewType> result =
   *     (ImmutableList) stream.filter(NewType.class::isInstance).collect(toImmutableList());
   * }

   * This does perform a little more work than necessary, so another option is to insert an
   * unchecked cast at some later point:
   *
   * {@snippet :
   * @SuppressWarnings("unchecked") // safe because of ::isInstance check
   * ImmutableList<NewType> result =
   *     (ImmutableList) stream.filter(NewType.class::isInstance).collect(toImmutableList());
   * }