Files
openlayers/src/ol/format/JSONFeature.js
2018-07-17 10:20:26 +02:00

161 lines
3.6 KiB
JavaScript

/**
* @module ol/format/JSONFeature
*/
import {inherits} from '../util.js';
import FeatureFormat from '../format/Feature.js';
import FormatType from '../format/FormatType.js';
/**
* @classdesc
* Abstract base class; normally only used for creating subclasses and not
* instantiated in apps.
* Base class for JSON feature formats.
*
* @abstract
* @extends {module:ol/format/Feature}
*/
class JSONFeature {
constructor() {
FeatureFormat.call(this);
}
/**
* @inheritDoc
*/
getType() {
return FormatType.JSON;
}
/**
* @inheritDoc
*/
readFeature(source, opt_options) {
return this.readFeatureFromObject(
getObject(source), this.getReadOptions(source, opt_options));
}
/**
* @inheritDoc
*/
readFeatures(source, opt_options) {
return this.readFeaturesFromObject(
getObject(source), this.getReadOptions(source, opt_options));
}
/**
* @abstract
* @param {Object} object Object.
* @param {module:ol/format/Feature~ReadOptions=} opt_options Read options.
* @protected
* @return {module:ol/Feature} Feature.
*/
readFeatureFromObject(object, opt_options) {}
/**
* @abstract
* @param {Object} object Object.
* @param {module:ol/format/Feature~ReadOptions=} opt_options Read options.
* @protected
* @return {Array.<module:ol/Feature>} Features.
*/
readFeaturesFromObject(object, opt_options) {}
/**
* @inheritDoc
*/
readGeometry(source, opt_options) {
return this.readGeometryFromObject(
getObject(source), this.getReadOptions(source, opt_options));
}
/**
* @abstract
* @param {Object} object Object.
* @param {module:ol/format/Feature~ReadOptions=} opt_options Read options.
* @protected
* @return {module:ol/geom/Geometry} Geometry.
*/
readGeometryFromObject(object, opt_options) {}
/**
* @inheritDoc
*/
readProjection(source) {
return this.readProjectionFromObject(getObject(source));
}
/**
* @abstract
* @param {Object} object Object.
* @protected
* @return {module:ol/proj/Projection} Projection.
*/
readProjectionFromObject(object) {}
/**
* @inheritDoc
*/
writeFeature(feature, opt_options) {
return JSON.stringify(this.writeFeatureObject(feature, opt_options));
}
/**
* @abstract
* @param {module:ol/Feature} feature Feature.
* @param {module:ol/format/Feature~WriteOptions=} opt_options Write options.
* @return {Object} Object.
*/
writeFeatureObject(feature, opt_options) {}
/**
* @inheritDoc
*/
writeFeatures(features, opt_options) {
return JSON.stringify(this.writeFeaturesObject(features, opt_options));
}
/**
* @abstract
* @param {Array.<module:ol/Feature>} features Features.
* @param {module:ol/format/Feature~WriteOptions=} opt_options Write options.
* @return {Object} Object.
*/
writeFeaturesObject(features, opt_options) {}
/**
* @inheritDoc
*/
writeGeometry(geometry, opt_options) {
return JSON.stringify(this.writeGeometryObject(geometry, opt_options));
}
/**
* @abstract
* @param {module:ol/geom/Geometry} geometry Geometry.
* @param {module:ol/format/Feature~WriteOptions=} opt_options Write options.
* @return {Object} Object.
*/
writeGeometryObject(geometry, opt_options) {}
}
inherits(JSONFeature, FeatureFormat);
/**
* @param {Document|Node|Object|string} source Source.
* @return {Object} Object.
*/
function getObject(source) {
if (typeof source === 'string') {
const object = JSON.parse(source);
return object ? /** @type {Object} */ (object) : null;
} else if (source !== null) {
return source;
} else {
return null;
}
}
export default JSONFeature;