```

`Optional[str]`을 `str` 대신 쓰게 되면, 특정 값이 실제로는 `None`이 될 수도 있는데 항상 `str`이라고 가정하는 상황에서 에디터가 에러를 찾게 도와줄 수 있습니다.

#### Generic(제네릭) 타입

이 타입은 대괄호 안에 매개변수를 가지며, 종류는:

* `List`
* `Tuple`
* `Set`
* `Dict`
* `Optional`
* ...등등

위와 같은 타입은 **Generic(제네릭) 타입** 혹은 **Generics(제네릭스)**라고 불립니다.

### 타입으로서의 클래스

변수의 타입으로 클래스를 선언할 수도 있습니다.

이름(name)을 가진 `Person` 클래스가 있다고 해봅시다.

 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */
package jcifs.internal;

import jcifs.CIFSContext;

/**
 * Generic interface for typed SMB request messages.
 * Extends the common request interface with type-safe response handling,

import com.google.common.collect.testing.Helpers;
import com.google.common.collect.testing.features.CollectionFeature;
import java.util.ArrayList;
import java.util.List;
import org.junit.Ignore;

/**
 * A generic JUnit test which tests {@code forEach} operations on a collection. Can't be invoked
 * directly; please see {@link com.google.common.collect.testing.CollectionTestSuiteBuilder}.
 *
 * @author Louis Wasserman
 */

import com.google.common.annotations.GwtCompatible;
import com.google.common.collect.testing.features.CollectionFeature;
import com.google.common.collect.testing.features.CollectionSize;
import org.junit.Ignore;

/**
 * A generic JUnit test which tests {@code lastIndexOf()} operations on a list. Can't be invoked
 * directly; please see {@link com.google.common.collect.testing.ListTestSuiteBuilder}.
 *
 * @author Chris Povirk
 */
@GwtCompatible

import static java.util.Arrays.asList;

import com.google.common.annotations.GwtCompatible;
import com.google.common.collect.testing.features.CollectionSize;
import org.junit.Ignore;

/**
 * A generic JUnit test which tests {@code toArray()} operations on a list. Can't be invoked
 * directly; please see {@link com.google.common.collect.testing.ListTestSuiteBuilder}.
 *
 * @author Chris Povirk
 */
@GwtCompatible

import com.google.common.annotations.GwtCompatible;
import com.google.common.collect.testing.features.CollectionFeature;
import org.junit.Ignore;

/**
 * A generic JUnit test which tests offer operations on a queue. Can't be invoked directly; please
 * see {@link com.google.common.collect.testing.CollectionTestSuiteBuilder}.
 *
 * @author Jared Levy
 */
@GwtCompatible

                case 4:
                    throw new NullPointerException("Null pointer");
                default:
                    throw new RuntimeException("Generic error");
                }
            }
        };
        ComponentUtil.register(mockSearchLogHelper, "searchLogHelper");

        // First execution - success

 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

package jcifs.internal.smb1.com;

import jcifs.Configuration;
import jcifs.internal.smb1.ServerMessageBlock;

/**
 * SMB1 blank response message.
 *
 * This is a generic response message for SMB commands that don't

 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

package jcifs.smb1.dcerpc;

/**
 * DCE/RPC error codes and fault constants for SMB1 compatibility
 */
public interface DcerpcError {

    /**
     * Generic fault code for other errors
     */

 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

package jcifs.dcerpc;

/**
 * DCE/RPC error codes and fault constants
 */
public interface DcerpcError {

    /**
     * Generic fault code for other errors
     */
    int DCERPC_FAULT_OTHER = 0x00000001;
    /**