JavaFx tableview排序非常慢，如何提高排序速度，就像在java swing中一样 [英] JavaFx tableview sort is really slow how to improve sort speed as in java swing
问题描述
我正在研究javaFx应用程序并创建了一个tableview，并且有大约100,000多行，包含10列。
I am working on javaFx application and have created a tableview and have around 100,000+ rows with 10 columns.
我还使用java swing Jtable创建了相同的表。
I have also created same table using java swing Jtable.
现在我需要排序性能在javaFx中更好，如果不比java swing的jtable更接近。
Now I need sorting performance to be better in javaFx if not better than some what near to java swing's jtable.
现在我正在使用sortorder（）通过单击列标题对数据进行排序，排序速度比Jtable慢20倍。
Right Now I am using sortorder() which sort data by clicking on column headers and sort speed is 20 times slower than Jtable.
任何人都可以帮忙吗？
谢谢
编辑：
我正在使用示例13.8在此链接中 http://docs.oracle.com/javafx/ 2 / ui_controls / table-view.htm
只需添加几行代码就可以通过生成随机数据来添加100,000行。
I am using example 13.8 in this link http://docs.oracle.com/javafx/2/ui_controls/table-view.htm just has added few line of code to just add 100,000 rows by generating random data.
推荐答案
花了一段时间，但我想我已经想到了这一点，至少在这个例子中。
It took a while, but I think I have figured this out, at least for this example.
在此示例中，Person类没有任何属性访问器（即有一个getFirstName（）方法，但没有firstNameProperty（）方法）。按列排序必须通过单元格值工厂访问列中每个单元格中的值。当没有属性访问器时，单元格值工厂将调用getFirstName（），然后在每次调用时将结果包装在新的ReadOnlyObjectWrapper中。
In this example, the Person class doesn't have any property accessors (i.e. there's a getFirstName() method, but no firstNameProperty() method). Sorting by columns has to access the value in each cell in the column via the cell value factory. When there's no property accessor, the cell value factory is going to call getFirstName() and then wrap the result in a new ReadOnlyObjectWrapper on each invocation.
如果确保表示行数据的类具有适当的属性访问器，然后检索该值的效率要高得多，因为它只返回对现有StringProperty的引用。
If you make sure the class representing the row data has the appropriate property accessors, then retrieving the value is much more efficient, as it merely returns a reference to the existing StringProperty.
此示例在我的系统上大约一秒钟内排序100,000行（MacBookPro 8GB RAM，四核）。您可以通过提供显式单元值工厂来提高性能，这可以满足计算单元格值时反射的需要。换句话说，替换
This example sorts 100,000 rows in approximately a second on my system (MacBookPro 8GB RAM, quad core). You can improve performance more by providing an explicit cell value factory, which gets around the need for reflection in computing the cell value. In other words, replace
firstNameCol.setCellValueFactory(
new PropertyValueFactory<Person, String>("firstName"));
with
firstNameCol.setCellValueFactory(new Callback<TableColumn.CellDataFeatures<Person,String>, ObservableValue<String>>() {
@Override
public ObservableValue<String> call(CellDataFeatures<Person, String> cdf) {
return cdf.getValue().firstNameProperty();
}
});
此处的性能节省并不那么显着。
The performance saving here is not as dramatic.
以下是完整示例：
import javafx.application.Application;
import javafx.beans.property.SimpleStringProperty;
import javafx.beans.property.StringProperty;
import javafx.beans.value.ObservableValue;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.geometry.Insets;
import javafx.scene.Group;
import javafx.scene.Scene;
import javafx.scene.control.*;
import javafx.scene.control.TableColumn.CellDataFeatures;
import javafx.scene.control.cell.PropertyValueFactory;
import javafx.scene.layout.HBox;
import javafx.scene.layout.VBox;
import javafx.scene.text.Font;
import javafx.stage.Stage;
import javafx.util.Callback;
import java.util.Arrays;
import java.util.Collections;
import java.util.Date;
import java.util.Random;
public class TableSortPerformanceTest extends Application {
public static void main(String[] args) {
launch(args);
}
@Override
public void start(Stage stage) {
Scene scene = new Scene(new Group());
stage.setTitle("Table View Sample");
stage.setWidth(550);
stage.setHeight(550);
final Label label = new Label("Address Book");
label.setFont(new Font("Arial", 20));
final TableView<Person> table = new TableView<Person>();
table.setEditable(true);
TableColumn<Person, String> firstNameCol = new TableColumn<Person, String>("First Name");
firstNameCol.setMinWidth(100);
firstNameCol.setCellValueFactory(
new PropertyValueFactory<Person, String>("firstName"));
firstNameCol.setCellValueFactory(new Callback<TableColumn.CellDataFeatures<Person,String>, ObservableValue<String>>() {
@Override
public ObservableValue<String> call(CellDataFeatures<Person, String> cdf) {
return cdf.getValue().firstNameProperty();
}
});
TableColumn<Person, String> lastNameCol = new TableColumn<Person, String>("Last Name");
lastNameCol.setMinWidth(100);
lastNameCol.setCellValueFactory(
new PropertyValueFactory<Person, String>("lastName"));
TableColumn<Person, String> emailCol = new TableColumn<Person, String>("Email");
emailCol.setMinWidth(200);
emailCol.setCellValueFactory(
new PropertyValueFactory<Person, String>("email"));
Random random = new Random();
for (int i = 0; i < 100000; i++) {
table.getItems().add(new Person(randomString(random), randomString(random), randomString(random)));
}
table.getColumns().addAll(Arrays.asList(firstNameCol, lastNameCol, emailCol));
long start = new Date().getTime();
Collections.sort(table.getItems());
long end = new Date().getTime();
System.out.println("Took: " + (end - start));
final TextField addFirstName = new TextField();
addFirstName.setPromptText("First Name");
addFirstName.setMaxWidth(firstNameCol.getPrefWidth());
final TextField addLastName = new TextField();
addLastName.setMaxWidth(lastNameCol.getPrefWidth());
addLastName.setPromptText("Last Name");
final TextField addEmail = new TextField();
addEmail.setMaxWidth(emailCol.getPrefWidth());
addEmail.setPromptText("Email");
final Button addButton = new Button("Add");
addButton.setOnAction(new EventHandler<ActionEvent>() {
@Override
public void handle(ActionEvent e) {
table.getItems().add(new Person(
addFirstName.getText(),
addLastName.getText(),
addEmail.getText()));
addFirstName.clear();
addLastName.clear();
addEmail.clear();
}
});
final HBox hb = new HBox(3);
hb.getChildren().addAll(addFirstName, addLastName, addEmail, addButton);
final VBox vbox = new VBox();
vbox.setSpacing(5);
vbox.setPadding(new Insets(10, 0, 0, 10));
vbox.getChildren().addAll(label, table, hb);
((Group) scene.getRoot()).getChildren().addAll(vbox);
stage.setScene(scene);
stage.show();
}
private String randomString(Random random) {
char[] chars = new char[20];
for (int i = 0; i < 20; i++) {
int nextInt = random.nextInt(26);
nextInt += random.nextBoolean() ? 65 : 97;
chars[i] = (char) nextInt;
}
return new String(chars);
}
public static class Person implements Comparable<Person> {
private final StringProperty firstName;
private final StringProperty lastName;
private final StringProperty email;
private Person(String fName, String lName, String email) {
this.firstName = new SimpleStringProperty(fName);
this.lastName = new SimpleStringProperty(lName);
this.email = new SimpleStringProperty(email);
}
public String getFirstName() {
return firstName.get();
}
public void setFirstName(String fName) {
firstName.set(fName);
}
public StringProperty firstNameProperty() {
return firstName ;
}
public String getLastName() {
return lastName.get();
}
public void setLastName(String fName) {
lastName.set(fName);
}
public StringProperty lastNameProperty() {
return lastName ;
}
public String getEmail() {
return email.get();
}
public void setEmail(String fName) {
email.set(fName);
}
public StringProperty emailProperty() {
return email ;
}
@Override
public int compareTo(Person o) {
return firstName.get().compareTo(o.getFirstName());
}
}
}
更新：注意这是固定的在JavaFX 8中。
UPDATE: Note this is fixed in JavaFX 8.
这篇关于JavaFx tableview排序非常慢，如何提高排序速度，就像在java swing中一样的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
