@Experimental
@ThreadSafe
public interface ProtoSession {

    /**
     * Returns immutable user properties to use for interpolation. The user properties have been configured directly
     * by the user, e.g. via the {@code -Dkey=value} parameter on the command line.
     *
     * @return the user properties, never {@code null}
     */
    @Nonnull
    Map<String, String> getUserProperties();

    /**

     * on his discretion, e.g. via the {@code -Dkey=value} parameter on the command line.
     *
     * @return The user properties, never {@code null}.
     */
    Properties getUserProperties();

    /**
     * Sets the user properties to use for interpolation. The user properties have been configured directly by the user
     * on his discretion, e.g. via the {@code -Dkey=value} parameter on the command line.
     *

    }

    /**
     * Sets the user properties to use for interpolation and profile activation. The user properties have been
     * configured directly by the user on his discretion, e.g. via the {@code -Dkey=value} parameter on the command
     * line.
     *
     * @param userProperties The user properties, may be {@code null}.
     * @return This context, never {@code null}.
     */
    @SuppressWarnings("unchecked")

    /**
     * Sets the user properties to use for interpolation and profile activation. The user properties have been
     * configured directly by the user on his discretion, e.g. via the {@code -Dkey=value} parameter on the command
     * line.
     *
     * @param userProperties The user properties, may be {@code null}.
     * @return This request, never {@code null}.
     */

    /**
     * Gets the user properties to use for interpolation and profile activation. The user properties have been
     * configured directly by the user on his discretion, e.g. via the {@code -Dkey=value} parameter on the command
     * line.
     *
     * @return The user properties, never {@code null}.
     */
    Map<String, String> getUserProperties();

    /**