# Package org.apache.sis.metadata.iso.content

package org.apache.sis.metadata.iso.content
Description of the dataset content. An explanation for this package is provided in the OpenGIS® javadoc. The remaining discussion on this page is specific to the SIS implementation.

## Overview

For a global overview of metadata in SIS, see the `org​.apache​.sis​.metadata` package javadoc.

Package overview
Class hierarchy | Aggregation hierarchy
--- | ---
ISO 19115 metadata `├─` Content information «abstract» `│ ├─` Feature catalogue `│ ├─` Feature catalogue description `│ └─` Coverage description `│ └─` Image description `├─` Feature type info `├─` Range dimension `│ └─` Sample dimension `│ └─` Band `└─` Range element description Code list `├─` Band definition `├─` Coverage content type `├─` Imaging condition `├─` Polarisation orientation `└─` Transfer function type | Content information «abstract» Feature catalogue description `└─` Feature type info Coverage description `├─` Attribute group `│ ├─` Coverage content type «code list» `│ └─` Range dimension `└─` Range element description Band `├─` Band definition «code list» `├─` Polarisation orientation «code list» `└─` Transfer function type «code list» Image description `└─` Imaging condition «code list»

## Null values, nil objects and collections

All constructors and setter methods accept `null` arguments. A null argument value means that the metadata element cannot be provided, and the reason for that is unspecified. Alternatively, users can specify why a metadata element is missing by providing a value created by `NilReason​.createNilObject(Class)`.

Unless otherwise noted in the Javadoc, all getter methods may return an empty collection, an empty array or `null` if the type is neither a collection or an array. Note that non-null values may be `NilObject`s.

Unless the metadata object has been marked as unmodifiable and unless otherwise noted in the Javadoc, all collections returned by getter methods are live: adding new elements in the collection modify directly the underlying metadata object.

Since:
  0.3

- Related Packages
  Package
  Description
  org.apache.sis.metadata.iso
  Root package for ISO 19115 metadata about resources (data or services).
- Classes
  Class
  Description
  AbstractContentInformation
  Description of the content of a resource.
  DefaultAttributeGroup
  Information about content type for groups of attributes for a specific range dimension.
  DefaultBand
  Range of wavelengths in the electromagnetic spectrum.
  DefaultCoverageDescription
  Information about the content of a grid data cell.
  DefaultFeatureCatalogueDescription
  Information identifying the feature catalogue or the conceptual schema.
  DefaultFeatureTypeInfo
  Information about the occurring feature type.
  DefaultImageDescription
  Information about an image's suitability for use.
  DefaultRangeDimension
  Information on the range of each dimension of a cell measurement value.
  DefaultRangeElementDescription
  Description of specific range elements.
  DefaultSampleDimension
  The characteristic of each dimension (layer) included in the resource.