# Instrument¶

public class Instrument extends AbstractRdcDomainObject

An instrument (e.g. a questionnaire) which was used in at least one Survey.

## Fields¶

### annotations¶

private I18nString annotations

Arbitrary additional text for this instrument. Must not contain more than 2048 characters.

### dataAcquisitionProjectId¶

private String dataAcquisitionProjectId

The id of the DataAcquisitionProject to which this instrument belongs. The dataAcquisitionProjectId must not be empty.

### description¶

private I18nString description

A short description of the instrument. It must be specified in at least one language and it must not contain more than 512 characters.

### id¶

private String id

The id of the instrument which uniquely identifies the instrument in this application. The id must not be empty and must be of the form ins-{{dataAcquisitionProjectId}}-ins{{number}}\$. The id must not contain more than 512 characters.

### number¶

private Integer number

The number of the instrument. Must not be empty and must be unique within the DataAcquisitionProject.

### studyId¶

private String studyId

The id of the OrderedStudy to which this instrument belongs. Must not be empty.

### subtitle¶

private I18nString subtitle

An optional subtitle of the instrument. It must not contain more than 2048 characters.

### surveyIds¶

private List<String> surveyIds

List of ids of Surveys of this DataAcquisitionProject. The instrument has been used in these Surveys. Must contain at least one element.

### surveyNumbers¶

private List<Integer> surveyNumbers

List of numbers of Surveys of this DataAcquisitionProject. The instrument has been used in these Surveys. Must contain at least one element.

### title¶

private I18nString title

The title of the instrument. It must be specified in at least one language and it must not contain more than 2048 characters.

### type¶

private String type

The type of this instrument. Must be one of InstrumentTypes and must not be empty.