com.luciad.format.geojson

LuciadLightspeedInterface ILcdGeoJsonShapeEncoder

public interface ILcdGeoJsonShapeEncoder

An encoder for encoding shapes to GeoJSON. This encoder can be plugged into a TLcdGeoJsonModelEncoder, for encoding shapes that the encoder does not support by default, or to override the default encoding behaviour.

An example implementation is shown below. This implementation can be used for adding support for ILcdCircle shape types to the TLcdGeoJsonModelEncoder:

  public static class CircleEncoder implements ILcdGeoJsonShapeEncoder {

    @Override
    public boolean canEncode(ILcdShape aShape) {
      return aShape instanceof ILcdCircle;
    }

    @Override
    public Object encode(ILcdShape aShape) throws IOException {
      if (!canEncode(aShape)) {
        throw new IOException("This encoder only supports circles.");
      }
      ILcdCircle circle = (ILcdCircle) aShape;

      Map<String, Object> map = new LinkedHashMap<>();
      map.put("type", "Circle");
      map.put("center", Arrays.asList(circle.getCenter().getX(), circle.getCenter().getY()));
      map.put("radius", circle.getRadius());

      // The resulting JSON geometry will be:
      // { "type": "Circle", "center": [ <x>, <y> ], "radius": <radius> }

      return map;
    }
  }

Since:

2023.1.04

Method Summary

Modifier and Type	Method and Description
boolean	canEncode(ILcdShape aShape) Checks whether the given shape can be encoded to GeoJSON by this encoder.
Object	encode(ILcdShape aShape) Encodes the given shape to an object that can directly be mapped to a JSON node.

Method Detail

canEncode

boolean canEncode(ILcdShape aShape)

Checks whether the given shape can be encoded to GeoJSON by this encoder.

Parameters:

aShape - the shape to encode

Returns:

whether the given shape can be encoded by this encoder

encode

Object encode(ILcdShape aShape)
       throws IOException

Encodes the given shape to an object that can directly be mapped to a JSON node. Accepted return types are:

• null: this gets mapped to a null JSON node.
• A primitive of type String, Boolean, Long, Integer, Short, Byte, Double or Float. This gets mapped to a primitive JSON node.
• A List containing accepted return types. This gets mapped to a JSON array.
• A Map containing String keys and accepted return types for values. This gets mapped to a JSON object node, with the map entries as properties.

See the ILcdGeoJsonShapeEncoder class javadoc for an example implementation.

Parameters:

aShape - the shape to encode

Returns:

a JSON-encodable object.

Throws:

IOException - when the shape could not be encoded