If the nested type is a managed type (Gradle can generate its implementation), you can define a nested property with:
```
interface NestedType {
    Property<String> getSomeProperty()
}
class Example {
    @Nested
    NestedType getNestedProperty()
}
```

import org.junit.jupiter.api.DisplayName;
import org.junit.jupiter.api.Nested;
import org.junit.jupiter.api.Test;

/**
 * Unit tests for {@link SmbFileFilter}. The filter interface is small; the
 * tests focus on the contract that implementations should honour and the
 * interaction with {@link SmbFile} instances. The tests make heavy use of
 * Mockito to guarantee that implementation classes do not inadvertently

import java.util.Collection;
import java.util.Map.Entry;
import org.jspecify.annotations.NullMarked;
import org.jspecify.annotations.Nullable;

/**
 * Creates multimaps, containing sample elements, to be tested.
 *
 * @author Louis Wasserman
 */
@GwtCompatible
@NullMarked
public interface TestMultimapGenerator<
        K extends @Nullable Object, V extends @Nullable Object, M extends Multimap<K, V>>

import java.util.Collection;
import java.util.Map.Entry;
import org.jspecify.annotations.NullMarked;
import org.jspecify.annotations.Nullable;

/**
 * Creates multimaps, containing sample elements, to be tested.
 *
 * @author Louis Wasserman
 */
@GwtCompatible
@NullMarked
public interface TestMultimapGenerator<
        K extends @Nullable Object, V extends @Nullable Object, M extends Multimap<K, V>>

        }

        @Test
        void testConstructorWithStringURL() throws MalformedURLException {
            // Arrange & Act
            SmbFile file = new SmbFile("smb://localhost/share/test.txt", mockCifsContext);

            // Assert
            assertNotNull(file);
            assertEquals("test.txt", file.getName());
        }

        @Test
        void testConstructorWithInvalidURL() {

            testBlock.setUseUnicode(true);
            assertEquals(10, testBlock.stringWireLength("Test", 0));
            assertEquals(11, testBlock.stringWireLength("Test", 1));
        }

        @Test
        @DisplayName("Test read string length")
        void testReadStringLength() {
            byte[] buffer = "Test\0Other".getBytes();

			expectedResult: true,
		},
	}

	for i, tc := range testCases {
		t.Run(fmt.Sprintf("Test_%d", i+1), func(t *testing.T) {
			cfg, err := ParseConfig(bytes.NewReader([]byte(tc.inputConfig)))
			if err != nil {
				t.Fatalf("Got unexpected error: %v", err)
			}

            return 0;
        }
    }

    @Nested
    @DisplayName("Interface Constants Tests")
    class InterfaceConstantsTests {

        @Test
        @DisplayName("Should have correct SMB_INFO_ALLOCATION constant value")
        void testSmbInfoAllocationConstant() {
            assertEquals((byte) -1, FileSystemInformation.SMB_INFO_ALLOCATION);
        }

        @Test

import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;
import org.mockito.Mock;
import org.mockito.MockitoAnnotations;

class MsrpcLsarOpenPolicy2Test {

    @Mock
    private LsaPolicyHandle mockPolicyHandle;

    @BeforeEach
    void setUp() {
        MockitoAnnotations.openMocks(this);
    }

    @Test
    void constructor_shouldInitializeFieldsCorrectly() {
        // Given

        }

        @Test
        @DisplayName("Should accept empty file ID in constructor")
        void testConstructorWithEmptyFileId() {
            byte[] emptyFileId = new byte[16];
            assertDoesNotThrow(() -> new Smb2WriteRequest(mockConfig, emptyFileId));
        }
    }

    @Nested
    @DisplayName("FileId Tests")
    class FileIdTests {

        @Test