code: package org.eclipse.milo.opcua.sdk.client.model.types.variables;
  
  import java.util.concurrent.CompletableFuture;
  
  import org.eclipse.milo.opcua.sdk.core.QualifiedProperty;
  import org.eclipse.milo.opcua.sdk.core.ValueRanks;
  import org.eclipse.milo.opcua.stack.core.UaException;
  import org.eclipse.milo.opcua.stack.core.types.builtin.ExpandedNodeId;
  import org.eclipse.milo.opcua.stack.core.types.builtin.LocalizedText;
  import org.eclipse.milo.opcua.stack.core.types.builtin.StatusCode;
  
  public interface OptionSetType extends BaseDataVariableType {
      QualifiedProperty<LocalizedText[]> OPTION_SET_VALUES = new QualifiedProperty<>(
          "http://opcfoundation.org/UA/",
          "OptionSetValues",
          ExpandedNodeId.parse("nsu=http://opcfoundation.org/UA/;i=21"),
          ValueRanks.OneDimension,
          LocalizedText[].class
      );
  
      QualifiedProperty<Boolean[]> BIT_MASK = new QualifiedProperty<>(
          "http://opcfoundation.org/UA/",
          "BitMask",
          ExpandedNodeId.parse("nsu=http://opcfoundation.org/UA/;i=1"),
          ValueRanks.OneDimension,
          Boolean[].class
      );
  
      /**
       * Get the local value of the OptionSetValues Node.
       * <p>
       * The returned value is the last seen; it is not read live from the server.
       *
       * @return the local value of the OptionSetValues Node.
       * @throws UaException if an error occurs creating or getting the OptionSetValues Node.
       */
      LocalizedText[] getOptionSetValues() throws UaException;
  
      /**
       * Set the local value of the OptionSetValues Node.
       * <p>
       * The value is only updated locally; it is not written to the server.
       *
       * @param optionSetValues the local value to set for the OptionSetValues Node.
       * @throws UaException if an error occurs creating or getting the OptionSetValues Node.
       */
      void setOptionSetValues(LocalizedText[] optionSetValues) throws UaException;
  
      /**
       * Read the value of the OptionSetValues Node from the server and update the local value if the
       * operation succeeds.
       *
       * @return the {@link LocalizedText[]} value read from the server.
       * @throws UaException if a service- or operation-level error occurs.
       */
      LocalizedText[] readOptionSetValues() throws UaException;
  
      /**
       * Write a new value for the OptionSetValues Node to the server and update the local value if
       * the operation succeeds.
       *
       * @param optionSetValues the {@link LocalizedText[]} value to write to the server.
       * @throws UaException if a service- or operation-level error occurs.
       */
      void writeOptionSetValues(LocalizedText[] optionSetValues) throws UaException;
  
      /**
       * An asynchronous implementation of {@link #readOptionSetValues()}.
       *
       * @return a CompletableFuture that completes successfully with the property value or completes
       * exceptionally if an operation- or service-level error occurs.
       */
      CompletableFuture<? extends LocalizedText[]> readOptionSetValuesAsync();
  
      /**
       * An asynchronous implementation of {@link #writeOptionSetValues(LocalizedText[])}.
       *
       * @return a CompletableFuture that completes successfully with the operation result or
       * completes exceptionally if a service-level error occurs.
       */
      CompletableFuture<StatusCode> writeOptionSetValuesAsync(LocalizedText[] optionSetValues);
  
      /**
       * Get the OptionSetValues {@link PropertyType} Node, or {@code null} if it does not exist.
       * <p>
       * The Node is created when first accessed and cached for subsequent calls.
       *
       * @return the OptionSetValues {@link PropertyType} Node, or {@code null} if it does not exist.
       * @throws UaException if an error occurs creating or getting the Node.
       */
      PropertyType getOptionSetValuesNode() throws UaException;
  
      /**
       * Asynchronous implementation of {@link #getOptionSetValuesNode()}.
       *
       * @return a CompletableFuture that completes successfully with the
       * ? extends PropertyType Node or completes exceptionally if an error occurs
       * creating or getting the Node.
       */
      CompletableFuture<? extends PropertyType> getOptionSetValuesNodeAsync();
  
      /**
       * Get the local value of the BitMask Node.
       * <p>
       * The returned value is the last seen; it is not read live from the server.
       *
       * @return the local value of the BitMask Node.
       * @throws UaException if an error occurs creating or getting the BitMask Node.
       */
      Boolean[] getBitMask() throws UaException;
  
      /**
       * Set the local value of the BitMask Node.
       * <p>
       * The value is only updated locally; it is not written to the server.
       *
       * @param bitMask the local value to set for the BitMask Node.
       * @throws UaException if an error occurs creating or getting the BitMask Node.
       */
      void setBitMask(Boolean[] bitMask) throws UaException;
  
      /**
       * Read the value of the BitMask Node from the server and update the local value if the
       * operation succeeds.
       *
       * @return the {@link Boolean[]} value read from the server.
       * @throws UaException if a service- or operation-level error occurs.
       */
      Boolean[] readBitMask() throws UaException;
  
      /**
       * Write a new value for the BitMask Node to the server and update the local value if
       * the operation succeeds.
       *
       * @param bitMask the {@link Boolean[]} value to write to the server.
       * @throws UaException if a service- or operation-level error occurs.
       */
      void writeBitMask(Boolean[] bitMask) throws UaException;
  
      /**
       * An asynchronous implementation of {@link #readBitMask()}.
       *
       * @return a CompletableFuture that completes successfully with the property value or completes
       * exceptionally if an operation- or service-level error occurs.
       */
      CompletableFuture<? extends Boolean[]> readBitMaskAsync();
  
      /**
       * An asynchronous implementation of {@link #writeBitMask(Boolean[])}.
       *
       * @return a CompletableFuture that completes successfully with the operation result or
       * completes exceptionally if a service-level error occurs.
       */
      CompletableFuture<StatusCode> writeBitMaskAsync(Boolean[] bitMask);
  
      /**
       * Get the BitMask {@link PropertyType} Node, or {@code null} if it does not exist.
       * <p>
       * The Node is created when first accessed and cached for subsequent calls.
       *
       * @return the BitMask {@link PropertyType} Node, or {@code null} if it does not exist.
       * @throws UaException if an error occurs creating or getting the Node.
       */
      PropertyType getBitMaskNode() throws UaException;
  
      /**
       * Asynchronous implementation of {@link #getBitMaskNode()}.
       *
       * @return a CompletableFuture that completes successfully with the
       * ? extends PropertyType Node or completes exceptionally if an error occurs
       * creating or getting the Node.
       */
      CompletableFuture<? extends PropertyType> getBitMaskNodeAsync();
  }
  