ArcGIS Runtime SDK for Java

Map Image Layer Tables

Demonstrates how to get a non-spatial table from an ArcGIS map image layer. It shows how to query such a table, as well as how to find related features in another table.

The non-spatial tables contained by a map service may contain additional information about sublayer features. Such information can be accessed by traversing table relationships defined in the service.

How it works

To query a map image layer's tables and find related features:

  1. Create an ArcGISMapImageLayer with the URL of a map image service.
  2. Load the layer and get one of it's tables with imageLayer.getTables().get(index).
  3. To query the table, create QueryParameters. You can use queryParameters.setWhereClause (sqlQuery) to filter the features returned. Use table.queryFeaturesAsync(parameters) to get a FeatureQueryResult.
  4. The FeatureQueryResult is an iterable, so simply loop through it to get each result Feature.
  5. To query for related features, get the table's relationship info with table.getLayerInfo() .getRelationshipInfos(). This returns a list of RelationshipInfos. Choose which one to base your query on.
  6. Now create RelatedQueryParameters passing in the RelationshipInfo. To query related features use table.queryRelatedFeaturesAsync(feature, relatedQueryParameters).
  7. This returns a list of RelatedFeatureQueryResults, each containing a set of related features.

Code

/*
 * Copyright 2018 Esri.
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not
 * use this file except in compliance with the License. You may obtain a copy of
 * the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations under
 * the License.
 */

package com.esri.samples.imagelayers.map_image_layer_tables;

import java.util.List;
import java.util.concurrent.ExecutionException;

import javafx.application.Application;
import javafx.geometry.Insets;
import javafx.geometry.Pos;
import javafx.scene.Scene;
import javafx.scene.control.Alert;
import javafx.scene.control.ListCell;
import javafx.scene.control.ListView;
import javafx.scene.layout.StackPane;
import javafx.stage.Stage;

import com.esri.arcgisruntime.arcgisservices.RelationshipInfo;
import com.esri.arcgisruntime.concurrent.ListenableFuture;
import com.esri.arcgisruntime.data.ArcGISFeature;
import com.esri.arcgisruntime.data.Feature;
import com.esri.arcgisruntime.data.FeatureQueryResult;
import com.esri.arcgisruntime.data.QueryParameters;
import com.esri.arcgisruntime.data.RelatedFeatureQueryResult;
import com.esri.arcgisruntime.data.RelatedQueryParameters;
import com.esri.arcgisruntime.data.ServiceFeatureTable;
import com.esri.arcgisruntime.geometry.Point;
import com.esri.arcgisruntime.layers.ArcGISMapImageLayer;
import com.esri.arcgisruntime.loadable.LoadStatus;
import com.esri.arcgisruntime.mapping.ArcGISMap;
import com.esri.arcgisruntime.mapping.Basemap;
import com.esri.arcgisruntime.mapping.Viewpoint;
import com.esri.arcgisruntime.mapping.view.Graphic;
import com.esri.arcgisruntime.mapping.view.GraphicsOverlay;
import com.esri.arcgisruntime.mapping.view.MapView;
import com.esri.arcgisruntime.symbology.SimpleMarkerSymbol;
import com.esri.arcgisruntime.symbology.SimpleRenderer;

public class MapImageLayerTablesSample extends Application {

  private MapView mapView;
  private GraphicsOverlay graphicsOverlay;
  private ServiceFeatureTable commentsTable;
  private ListView<Feature> commentsListView;

  /**
   * Starting point of this application.
   *
   * @param args arguments to this application.
   */
  public static void main(String[] args) {

    Application.launch(args);
  }

  @Override
  public void start(Stage stage) {

    try {
      // create a stack pane and application scene
      StackPane stackPane = new StackPane();
      Scene scene = new Scene(stackPane);
      scene.getStylesheets().add(getClass().getResource("/css/style.css").toExternalForm());

      // size the stage and add a title
      stage.setTitle("Map Image Layer Tables Sample");
      stage.setWidth(800);
      stage.setHeight(700);
      stage.setScene(scene);
      stage.show();

      // create a map with a basemap
      ArcGISMap map = new ArcGISMap(Basemap.createStreetsVector());

      // create and add a map image layer to the map
      // the map image layer contains a feature table with related spatial and non-spatial comment features
      ArcGISMapImageLayer imageLayer = new ArcGISMapImageLayer(
          "https://sampleserver6.arcgisonline.com/arcgis/rest/services/ServiceRequest/MapServer");
      map.getOperationalLayers().add(imageLayer);

      // create a map view and set the map to it
      mapView = new MapView();
      mapView.setMap(map);

      // create a graphics overlay to show the related spatial features in
      graphicsOverlay = new GraphicsOverlay();
      mapView.getGraphicsOverlays().add(graphicsOverlay);

      // show the related graphics as cyan circles
      SimpleRenderer renderer = new SimpleRenderer();
      renderer.setSymbol(new SimpleMarkerSymbol(SimpleMarkerSymbol.Style.CIRCLE, 0xFF00FFFF, 14));
      graphicsOverlay.setRenderer(renderer);

      // create a list view to show the non-spatial comment features
      commentsListView = new ListView<>();
      commentsListView.setMaxSize(200.0, 150.0);
      // show the comments attribute of the feature in the list
      commentsListView.setCellFactory(listView -> new ListCell<Feature>() {
        @Override
        protected void updateItem(Feature item, boolean empty) {
          super.updateItem(item, empty);
          if (item != null) {
            ArcGISFeature feature = (ArcGISFeature) item;
            setText((String) feature.getAttributes().get("comments"));
          }
        }
      });

      // when a comment is selected, query its related spatial features and show the first result on the map
      commentsListView.getSelectionModel().selectedItemProperty().addListener(observable -> showRelatedRequests());

      // when the layer is loaded, get the comment features
      imageLayer.addDoneLoadingListener(() -> {
        if (imageLayer.getLoadStatus() == LoadStatus.LOADED) {
          // zoom to the layer's extent
          mapView.setViewpoint(new Viewpoint(imageLayer.getFullExtent()));

          // get the comments feature table
          commentsTable = imageLayer.getTables().get(0);

          // create query parameters to get features that have non-empty comments
          QueryParameters queryParameters = new QueryParameters();
          queryParameters.setWhereClause("requestid <> '' AND comments <> ''");

          // query the comments table for features
          ListenableFuture<FeatureQueryResult> featureQuery = commentsTable.queryFeaturesAsync(queryParameters);
          featureQuery.addDoneListener(() -> {
            try {
              // add the returned features to the list view
              FeatureQueryResult results = featureQuery.get();
              for (Feature f : results) {
                commentsListView.getItems().addAll(f);
              }
            } catch (InterruptedException | ExecutionException ex) {
              new Alert(Alert.AlertType.ERROR, "Error querying comment features");
            }
          });
        } else {
          new Alert(Alert.AlertType.ERROR, imageLayer.getLoadError().getMessage()).show();
        }
      });

      // add the mapview and controls to the stack pane
      stackPane.getChildren().addAll(mapView, commentsListView);
      StackPane.setAlignment(commentsListView, Pos.TOP_LEFT);
      StackPane.setMargin(commentsListView, new Insets(10, 0, 0, 10));

    } catch (Exception e) {
      // on any error, display the stack trace.
      e.printStackTrace();
    }
  }

  /**
   * Queries for spatial features related to the selected comment in the list view and shows the first result on the
   * map as a graphic.
   */
  private void showRelatedRequests() {
    // clear any previous results
    graphicsOverlay.getGraphics().clear();

    // get the selected comment feature from the list view
    Feature selectedCommentFeature = commentsListView.getSelectionModel().getSelectedItem();
    if (selectedCommentFeature != null) {

      // get the relationships info between layers in the table
      ArcGISFeature feature = (ArcGISFeature) selectedCommentFeature;
      List<RelationshipInfo> relationshipInfos = commentsTable.getLayerInfo().getRelationshipInfos();
      if (!relationshipInfos.isEmpty()) {

        // use the first relationship for the related query parameters
        RelationshipInfo commentsRelationshipInfo = relationshipInfos.get(0);
        RelatedQueryParameters relatedQueryParameters = new RelatedQueryParameters(commentsRelationshipInfo);
        relatedQueryParameters.setReturnGeometry(true);

        // query the table for related features using the parameters
        ListenableFuture<List<RelatedFeatureQueryResult>> relatedFeaturesRequest = commentsTable
            .queryRelatedFeaturesAsync(feature, relatedQueryParameters);
        relatedFeaturesRequest.addDoneListener(() -> {
          try {
            // loop through the returned related features
            List<RelatedFeatureQueryResult> results = relatedFeaturesRequest.get();
            if (!results.isEmpty()) {
              RelatedFeatureQueryResult relatedResult = results.get(0);
              if (relatedResult.iterator().hasNext()) {
                // get the first related feature
                ArcGISFeature relatedFeature = (ArcGISFeature) relatedResult.iterator().next();
                // load the feature and get its geometry to show as a graphic on the map
                relatedFeature.loadAsync();
                relatedFeature.addDoneLoadingListener(() -> {
                  if (relatedFeature.getLoadStatus() == LoadStatus.LOADED) {
                    Point point = (Point) relatedFeature.getGeometry();
                    Graphic graphic = new Graphic(point);
                    graphicsOverlay.getGraphics().add(graphic);
                    // zoom to the graphic
                    mapView.setViewpointCenterAsync(point, 40000);
                  }
                });
              }
            } else {
              new Alert(Alert.AlertType.INFORMATION, "No related features found").show();
            }
          } catch (InterruptedException | ExecutionException ex) {
            new Alert(Alert.AlertType.ERROR, "Failed to query relationships").show();
          }
        });
      }
    }

  }

  @Override
  public void stop() {

    // releases resources when the application closes
    if (mapView != null) {
      mapView.dispose();
    }
  }
}


In this topic
  1. How it works
  2. Code