ArcGIS Runtime SDK for Java

Feature Layer Query

Demonstrates how to query a FeatureLayer from a FeatureTable.

How it works

To query a Feature from your FeatureLayer:

  1. Create a ServiceFeatureTable from a URL.
  2. Create a feature layer from the service feature table.
  3. Create a QueryParameters object and specified the where clause on it with QueryParameters.setWhereClause() from the text entered by the user.
  4. Fire the query on the service feature table using ServiceFeatureTable.queryFeaturesAsync(query).
  5. Once complete get the feature's from the FeatureQueryResult.

Code

/*
 * Copyright 2017 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.featurelayers.feature_layer_query;

import javafx.application.Application;
import javafx.application.Platform;
import javafx.geometry.Insets;
import javafx.geometry.Pos;
import javafx.scene.Scene;
import javafx.scene.control.Alert;
import javafx.scene.control.Alert.AlertType;
import javafx.scene.control.Button;
import javafx.scene.control.Label;
import javafx.scene.control.TextField;
import javafx.scene.layout.HBox;
import javafx.scene.layout.StackPane;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;

import com.esri.arcgisruntime.concurrent.ListenableFuture;
import com.esri.arcgisruntime.data.Feature;
import com.esri.arcgisruntime.data.FeatureQueryResult;
import com.esri.arcgisruntime.data.QueryParameters;
import com.esri.arcgisruntime.data.ServiceFeatureTable;
import com.esri.arcgisruntime.geometry.Envelope;
import com.esri.arcgisruntime.geometry.Point;
import com.esri.arcgisruntime.geometry.SpatialReferences;
import com.esri.arcgisruntime.layers.FeatureLayer;
import com.esri.arcgisruntime.loadable.LoadStatus;
import com.esri.arcgisruntime.mapping.ArcGISMap;
import com.esri.arcgisruntime.mapping.Basemap;
import com.esri.arcgisruntime.mapping.view.MapView;
import com.esri.arcgisruntime.symbology.SimpleFillSymbol;
import com.esri.arcgisruntime.symbology.SimpleLineSymbol;
import com.esri.arcgisruntime.symbology.SimpleRenderer;

public class FeatureLayerQuerySample extends Application {

  private Alert dialog;

  private MapView mapView;
  private FeatureLayer featureLayer;
  private ServiceFeatureTable featureTable;
  private Point startPoint;
  private ListenableFuture<FeatureQueryResult> tableQueryResult;

  private static final String SERVICE_FEATURE_URL =
      "https://sampleserver6.arcgisonline.com/arcgis/rest/services/USA/MapServer/2";
  private static final int SCALE = 100000000;

  @Override
  public void start(Stage stage) throws Exception {

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

      // set title, size, and add scene to stage
      stage.setTitle("Feature Layer Query Sample");
      stage.setWidth(800);
      stage.setHeight(700);
      stage.setScene(scene);
      stage.show();

      // create a control panel
      VBox vBoxControl = new VBox(6);
      vBoxControl.setMaxSize(250, 80);
      vBoxControl.getStyleClass().add("panel-region");

      // create area for searching
      Label searchLabel = new Label("Search for a State:");
      searchLabel.getStyleClass().add("panel-label");
      TextField searchField = new TextField();
      searchField.setMaxWidth(150);
      Button searchButton = new Button("Search");
      HBox searchBox = new HBox(5);
      searchBox.getChildren().addAll(searchField, searchButton);
      searchBox.setDisable(true);

      // create dialog to display alert information
      dialog = new Alert(AlertType.WARNING);

      // search for the state that was entered
      searchButton.setOnAction(e -> {
        // clear the selection of the feature
        featureLayer.clearSelection();
        String stateText = searchField.getText();

        if (stateText.trim().length() > 0) {
          searchForState(stateText);
        } else {
          dialog.setContentText("State Not Found! Add a valid state name.");
          dialog.showAndWait();
          mapView.setViewpointCenterAsync(startPoint, SCALE);
        }
      });

      // add search label and box to the control panel
      vBoxControl.getChildren().addAll(searchLabel, searchBox);

      // create a starting point for the view
      startPoint = new Point(-11000000, 5000000, SpatialReferences.getWebMercator());

      // set fill orange (0xFFFFCC00) color for the US states with a black color
      // (0xFF000000) outline
      SimpleLineSymbol lineSymbol = new SimpleLineSymbol(SimpleLineSymbol.Style.SOLID, 0xFF000000, 1);
      SimpleFillSymbol fillSymbol = new SimpleFillSymbol(SimpleFillSymbol.Style.SOLID, 0xFFFFCC00, lineSymbol);

      // create a service feature table
      featureTable = new ServiceFeatureTable(SERVICE_FEATURE_URL);

      // create a feature layer from table
      featureLayer = new FeatureLayer(featureTable);
      featureLayer.setOpacity(0.8f);

      // enable search once the feature layer is loaded
      featureLayer.addDoneLoadingListener(() -> {
        if (featureLayer.getLoadStatus() == LoadStatus.LOADED) {
          searchBox.setDisable(false);
        } else {
          Alert alert = new Alert(Alert.AlertType.ERROR, "Feature Layer Failed to Load!");
          alert.show();
        }
      });

      // set renderer for feature layer
      featureLayer.setRenderer(new SimpleRenderer(fillSymbol));

      // create a ArcGISMap with basemap topographic
      final ArcGISMap map = new ArcGISMap(Basemap.createTopographic());

      // add feature layer to operational layers
      map.getOperationalLayers().add(featureLayer);

      // create a view for this ArcGISMap
      mapView = new MapView();
      mapView.setMap(map);

      // set viewpoint to the start point
      mapView.setViewpointCenterAsync(startPoint, SCALE);

      // add the map view and control panel to stack pane
      stackPane.getChildren().addAll(mapView, vBoxControl);
      StackPane.setAlignment(vBoxControl, Pos.TOP_LEFT);
      StackPane.setMargin(vBoxControl, new Insets(10, 0, 0, 10));
    } catch (Exception e) {
      // on any error, display the stack trace
      e.printStackTrace();
    }
  }

  /**
   * Searches for a US state inside the current ServiceFeatureTable.
   * 
   * @param state a US state that is being searched
   */
  private void searchForState(String state) {

    // create a query for the state that was entered
    QueryParameters query = new QueryParameters();
    query.setWhereClause("upper(STATE_NAME) LIKE '" + state.toUpperCase() + "'");

    // search for the state feature in the feature table
    tableQueryResult = featureTable.queryFeaturesAsync(query);

    tableQueryResult.addDoneListener(() -> {
      try {
        // get the result from the query
        FeatureQueryResult result = tableQueryResult.get();
        // if a state feature was found
        if (result.iterator().hasNext()) {
          // get state feature and zoom to it
          Feature feature = result.iterator().next();
          Envelope envelope = feature.getGeometry().getExtent();
          mapView.setViewpointGeometryAsync(envelope, 200);

          // set the state feature to be selected
          featureLayer.selectFeature(feature);
        } else {
          Platform.runLater(() -> {
            dialog.setContentText("State Not Found! Add a valid state name.");
            dialog.showAndWait();
            mapView.setViewpointCenterAsync(startPoint, SCALE);
          });
        }
      } catch (Exception e) {
        // on any error, display the stack trace
        e.printStackTrace();
      }
    });
  }

  /**
   * Stops and releases all resources used in application.
   */
  @Override
  public void stop() throws Exception {

    if (mapView != null) {
      mapView.dispose();
    }
  }

  /**
   * Opens and runs application.
   *
   * @param args arguments passed to this application
   */
  public static void main(String[] args) {

    Application.launch(args);
  }

}


In this topic
  1. How it works
  2. Code