com.bekwam.examples.javafx.memorytests.BigTableController.java Source code

Introduction

Here is the source code for com.bekwam.examples.javafx.memorytests.BigTableController.java

Source

/*
 * Copyright 2016 Bekwam, Inc
 *
 * 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.bekwam.examples.javafx.memorytests;

import java.util.ArrayList;
import java.util.LinkedList;
import java.util.List;
import java.util.Queue;

import org.apache.commons.lang3.RandomStringUtils;

import javafx.beans.property.BooleanProperty;
import javafx.beans.property.ReadOnlyObjectWrapper;
import javafx.beans.property.SimpleBooleanProperty;
import javafx.beans.value.ObservableValue;
import javafx.collections.FXCollections;
import javafx.collections.ObservableList;
import javafx.event.EventHandler;
import javafx.fxml.FXML;
import javafx.scene.control.Button;
import javafx.scene.control.TableColumn;
import javafx.scene.control.TableColumn.CellDataFeatures;
import javafx.scene.control.TableColumn.CellEditEvent;
import javafx.scene.control.TablePosition;
import javafx.scene.control.TableView;
import javafx.scene.control.cell.PropertyValueFactory;
import javafx.scene.control.cell.TextFieldTableCell;

/**
 * @author carl
 *
 */
public class BigTableController {

    private final static int NUM_RECORDS = 20_000_000;

    @FXML
    TableColumn<MyObject, Number> tcId;

    @FXML
    TableColumn<MyObject, String> tcData;

    @FXML
    TableView<MyObject> tblObjects;

    @FXML
    Button btnSave;

    private final BooleanProperty dirtyFlag = new SimpleBooleanProperty();

    private final Queue<UpdateObject> updateList = new LinkedList<>();

    static <T, S> T getObjectAtEvent(CellEditEvent<T, S> evt) {

        TableView<T> tableView = evt.getTableView();

        ObservableList<T> items = tableView.getItems();

        TablePosition<T, S> tablePosition = evt.getTablePosition();

        int rowId = tablePosition.getRow();

        T obj = items.get(rowId);

        return obj;
    }

    private final EventHandler<TableColumn.CellEditEvent<MyObject, String>> dataEditCommitHandler = (evt) -> {
        if (!dirtyFlag.get()) {
            dirtyFlag.set(true);
        }
        MyObject obj = getObjectAtEvent(evt);
        String oldData = obj.getData();
        obj.setData(evt.getNewValue());
        updateList.add(new UpdateObject(obj.getId(), obj.getData(), oldData));
    };

    int pvCounter = 0;

    @FXML
    public void initialize() {

        btnSave.disableProperty().bind(dirtyFlag.not());

        // id is read-only
        /*      tcId.setCellValueFactory(new PropertyValueFactory<MyObject,Number>("id") {
            
                 @Override
                 public ObservableValue<Number> call(CellDataFeatures<MyObject, Number> param) {
        return new ReadOnlyObjectWrapper<Number>(param.getValue().getId());
                 }
                     
              });      
        */
        tcId.setCellValueFactory(new PropertyValueFactory<MyObject, Number>("id"));

        tcData.setCellValueFactory(new PropertyValueFactory<MyObject, String>("data") {
            @Override
            public ObservableValue<String> call(CellDataFeatures<MyObject, String> param) {
                System.out.println("pvCounter=" + pvCounter++);
                return new ReadOnlyObjectWrapper<String>(param.getValue().getData());
            }

        });
        tcData.setCellFactory(TextFieldTableCell.forTableColumn());
        tcData.setOnEditCommit(dataEditCommitHandler);

    }

    private List<MyObject> fetchData() {

        List<MyObject> objectsFromDataSource = new ArrayList<>();

        for (int i = 0; i < NUM_RECORDS; i++) {
            objectsFromDataSource.add(new MyObject((long) i, RandomStringUtils.randomAlphabetic(20)));
        }

        return objectsFromDataSource;
    }

    @FXML
    public void loadTable() {

        //
        // load the data into domain objects
        //
        List<MyObject> objectsFromDataSource = fetchData();

        //
        // put in control
        //
        tblObjects.setItems(FXCollections.observableList(objectsFromDataSource));

        // Uncomment for "Scroll Time" blog post
        //      scrollEntireTable();
    }

    /**
     * Uncomment for "Scroll Time" blog post
     */
    /*   private void scrollEntireTable() {
          new Thread() {
     @Override
     public void run() {            
        for( int i=50; i<NUM_RECORDS; i=i+50 ) {
           final int pos = i;
           Platform.runLater(() -> tblObjects.scrollTo( pos ));               
        }
     }
          }.start();
       }
    */
    @FXML
    public void save() {

        UpdateObject uo = null;
        while ((uo = updateList.poll()) != null) {
            System.out.println("updating " + uo);
        }

        dirtyFlag.set(false);
    }
}