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For example, if you have a GeoJSON file like this with a polygon(simple file for the test)

"type": "FeatureCollection", "features": [ "type": "Feature", "properties": {}, "geometry": { "type": "Polygon", "coordinates": [ -4.658203125, 41.343824581185686 -5.6689453125, 39.13006024213511 -1.9335937499999998, 39.16414104768742 -1.3623046875, 41.21172151054787 -4.658203125, 41.343824581185686

The point:

Geometry point2 = new WKTReader().read("POINT (-3.2958984375 40.44694705960048)");
And you want to load the geoJSON file in your program to test in this polygon contains the point, how could you do it in Java using JTS?
Other option could be use GeoTools with GeoJson plugin but i'm not able to parse a GeoJson file
What I have tried
Using GEOTOOLS like this
String content = new String(Files.readAllBytes(Paths.get("file.geojson")), "UTF-8");
GeometryJSON gjson = new GeometryJSON();
Reader reader = new StringReader(content);
Polygon p = gjson.readPolygon(reader);
System.out.println("polygon: " + p);
The problem here is that polygon p only contains the last polygon of the geojson file. If this file have many polygons, how should I parse it?
Using JTS2GEOJSON like this
String content = new String(Files.readAllBytes(Paths.get("file.geojson")), "UTF-8");
System.out.println("content: " + content);
GeoJSONReader reader1 = new GeoJSONReader();
Geometry geometry = reader1.read(content);
This code fail is this line:
Geometry geometry = reader1.read(content);
With this error:
Exception in thread "main" java.lang.UnsupportedOperationException
    at org.wololo.jts2geojson.GeoJSONReader.read(GeoJSONReader.java:51)
    at org.wololo.jts2geojson.GeoJSONReader.read(GeoJSONReader.java:21)
    at org.wololo.jts2geojson.GeoJSONReader.read(GeoJSONReader.java:16)
This error is due i'm trying to read a FeatureCollections from GeoJson file. It works if I tried with this simple string:
   String content = "{\n" +
                "        \"type\": \"Polygon\",\n" +
                "        \"coordinates\": [\n" +
                "          [\n" +
                "            [\n" +
                "              -4.141845703125,\n" +
                "              40.9218144123785\n" +
                "            ],\n" +
                "            [\n" +
                "              -4.603271484375,\n" +
                "              40.002371935876475\n" +
                "            ],\n" +
                "            [\n" +
                "              -3.5595703125,\n" +
                "              39.757879992021756\n" +
                "            ],\n" +
                "            [\n" +
                "              -2.548828125,\n" +
                "              40.43858586704331\n" +
                "            ],\n" +
                "            [\n" +
                "              -3.2080078125,\n" +
                "              41.12074559016745\n" +
                "            ],\n" +
                "            [\n" +
                "              -4.141845703125,\n" +
                "              40.9218144123785\n" +
                "            ]\n" +
                "          ]\n" +
                "        ]\n" +
                "      }";
If you are using GeoTools then you need to start thinking in terms of DataStores and FeatureCollections. There is lots of built in smarts (much of it using JTS) to handle filtering etc which saves you a lot if potential issues.
File inFile = new File("/home/ian/Data/states/states.geojson");
Map<String, Object> params = new HashMap<>();
params.put(GeoJSONDataStoreFactory.URLP.key, URLs.fileToUrl(inFile));
DataStore newDataStore = DataStoreFinder.getDataStore(params);
String pt = "POINT (-107 42)";
FilterFactory2 ff = CommonFactoryFinder.getFilterFactory2();
SimpleFeatureSource featureSource = newDataStore.getFeatureSource(newDataStore.getTypeNames()[0]);
Filter f = ff.contains(ff.property(featureSource.getSchema().getGeometryDescriptor().getLocalName()),
    ff.literal(pt));
SimpleFeatureCollection collection = featureSource.getFeatures(f);
if (collection.size() > 0) {
  try (SimpleFeatureIterator itr = collection.features()) {
    while (itr.hasNext()) {
      System.out.println(itr.next());
This will need the following in your pom.xml:
<dependency>
   <groupId>org.geotools</groupId>
   <artifactId>gt-geojsondatastore</artifactId>
   <version>${geotools.version}</version>
</dependency>
<dependency>
   <groupId>org.geotools</groupId>
   <artifactId>gt-shapefile</artifactId>
   <version>${geotools.version}</version>
 </dependency>
                it would be possible to do it using an InputStream inFile instead of File inFile? I have tried but it doesn't work here: URLs.fileToUrl(inFile) The way I've done is read from InputStream, create a temporary file and copy to to him but if I run this code in AWS it fails and I think is due to create a file (because in local run without problem)
– IoT user
                Jan 14, 2019 at 15:10
                No, you need either a real URL or a file converted to a URL. May be using java.tempfile might help?
– Ian Turton
                Jan 14, 2019 at 15:13
                That is what we are using: File tempFile = File.createTempFile("prefix-", ".geojson"); tempFile.deleteOnExit(); and if I run it locally with apache Flink all works well. The problem is when I run it in Kinesis Data Analytics no error have been shown but the method doesn't work because I don't have any result
– IoT user
                Jan 14, 2019 at 16:50
                I think this is probably going to be a new question for AWS experts - all I can suggest is checking the file exists in the code?
– Ian Turton
                Jan 14, 2019 at 17:08
                Hi @IanTurton, would you help me with this question? gis.stackexchange.com/q/330030/146554
– Felipe
                Jul 26, 2019 at 8:19
With the GeoJsonReader class you can read a GeoJson Geometry from a JSON fragment into a Geometry:
http://locationtech.github.io/jts/javadoc/org/locationtech/jts/io/geojson/GeoJsonReader.html
Then, test whether that geometry (geojson polygon) contains the argument geometry (wkt point):
http://locationtech.github.io/jts/javadoc/org/locationtech/jts/geom/Geometry.html#contains(org.locationtech.jts.geom.Geometry)
        
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