如何在 main class JavaJDK NetBeans 中使用文本字段值

how to use Textfield value in main class JavaJDK NetBeans

我有一个 java 并且很成功! https://pastebin.com/VbxeFKFz 现在我想用 jdk netbeans 制作一个简单的表格,其中包含 5 个文本字段和按钮以及标签来显示结果,但我有错误,我认为发生是因为我在 Class Start 中使用我的方法,但我现在不知道如何在 main class 中使用我的方法(我的方法 + 按钮和工具代码) 我的代码:

package knnjdk;
import java.util.*;
import javafx.application.Application;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.Label;
import javafx.scene.control.TextField;
import javafx.scene.layout.GridPane;
import javafx.scene.layout.StackPane;
import javafx.stage.Stage;


public class KnnJDK extends Application {

@Override

public void start(Stage primaryStage) {
    GridPane grid = new GridPane();
    // Labels & inputs Settings
    Label number1 = new Label("Data 1 :");
    Label number2 = new Label("Data 2 :");
    Label number3 = new Label("Data 3 :");
    Label number4 = new Label("Data 4 :");
    Label number5 = new Label("Data 5 :");
    Label resultat1 = new Label("The Result");
    TextField txt1 = new TextField();
    TextField txt2 = new TextField();
    TextField txt3 = new TextField();
    TextField txt4 = new TextField();
    TextField txt5 = new TextField();
    grid.add(number1,0,0);
    grid.add(number2,0,1);
    grid.add(number3,0,2);
    grid.add(number4,0,3);
    grid.add(number5,0,4);
    grid.add(resultat1,0,6);
    grid.add(txt1,1,0);
    grid.add(txt2,1,1);
    grid.add(txt3,1,2);
    grid.add(txt4,1,3);
    grid.add(txt5,1,4);
    Button butt = new Button();
    butt.setText("Applique KPPV");
    grid.add(butt,0,5);
    // My Main Method
    ///////////////////////////////////
    double insertedInt = Double.parseDouble(txt1.getText());
    double insertedInt2 = Double.parseDouble(txt2.getText());
    double insertedInt3 = Double.parseDouble(txt3.getText());
    double insertedInt4 = Double.parseDouble(txt4.getText());
    double insertedInt5 = Double.parseDouble(txt5.getText());
    double[] query = {insertedInt, insertedInt2, insertedInt3, insertedInt4, insertedInt5};

    int k = 10;// K : Welaya List Counts  
    List<City> cityList = new ArrayList<City>();
    List<Result> resultList = new ArrayList<Result>();   
    cityList.add(new City(instances[0],"IRIS0"));
    cityList.add(new City(instances[1],"IRIS1"));
    cityList.add(new City(instances[2],"IRIS2"));
    cityList.add(new City(instances[3],"IRIS3"));
    cityList.add(new City(instances[4],"IRIS4"));
    cityList.add(new City(instances[5],"IRIS5"));
    cityList.add(new City(instances[6],"IRIS6"));
    cityList.add(new City(instances[7],"IRIS7"));
    cityList.add(new City(instances[8],"IRIS8"));
    cityList.add(new City(instances[9],"IRIS9"));
    //find distances
    for(City city : cityList){
        double dist = 0.0;  
        for(int j = 0; j < city.cityAttributes.length; j++){             
            dist += Math.pow(city.cityAttributes[j] - query[j], 2) ;
        }
        double distance = Math.sqrt( dist );
        resultList.add(new Result(distance,city.cityName));

    } 


    Collections.sort(resultList, new DistanceComparator());
    String[] ss = new String[k];
    for(int x = 0; x < k; x++){
        ss[x] = resultList.get(x).cityName;
    }
    String majClass = findMajorityClass(ss);
    //System.out.println("The Nearest IRIS Class is : "+majClass);   



    ///////////////////////////////////
    Scene scene = new Scene(grid, 300, 250);


    // Final Action
    butt.setOnAction(event->{
        resultat1.setText(majClass);
    });
    primaryStage.setTitle("KNN With JDK");
    primaryStage.setScene(scene);
    primaryStage.show();

}

/**
 * @param args the command line arguments
 */
public static void main(String[] args) {
    launch(args);

}
// My Method
// our Data Base
static double[][] instances = {
        {6.300000,2.500000,5.000000,1.900000,3.000000},
        {6.900000,3.200000,5.700000,2.300000,3.000000},
        {5.100000,3.800000,1.900000,0.400000,1.000000},
        {6.600000,2.900000,4.600000,1.300000,2.000000},
        {5.700000,4.400000,1.500000,0.400000,1.000000},
        {4.600000,3.400000,1.400000,0.300000,1.000000},
        {4.300000,3.000000,1.100000,0.100000,1.000000},
        {6.900000,3.100000,5.100000,2.300000,3.000000},
        {5.100000,3.700000,1.500000,0.400000,1.000000},
        {6.100000,2.800000,4.700000,1.200000,2.000000},

};
private static String findMajorityClass(String[] array)
{
    //add the String array to a HashSet to get unique String values
    Set<String> h = new HashSet<String>(Arrays.asList(array));
    //convert the HashSet back to array
    String[] uniqueValues = h.toArray(new String[0]);
    //counts for unique strings
    int[] counts = new int[uniqueValues.length];
    // loop thru unique strings and count how many times they appear in origianl array   
    for (int i = 0; i < uniqueValues.length; i++) {
        for (int j = 0; j < array.length; j++) {
            if(array[j].equals(uniqueValues[i])){
                counts[i]++;
            }
        }        
    }

    for (int i = 0; i < uniqueValues.length; i++)
        System.out.println(uniqueValues[i]);
    for (int i = 0; i < counts.length; i++)
        System.out.println(counts[i]);


    int max = counts[0];
    for (int counter = 1; counter < counts.length; counter++) {
        if (counts[counter] > max) {
            max = counts[counter];
        }
    }
    System.out.println("max # of occurences: "+max);
    int freq = 0;
    for (int counter = 0; counter < counts.length; counter++) {
        if (counts[counter] == max) {
            freq++;
        }
    }
    int index = -1;
    if(freq==1){
        for (int counter = 0; counter < counts.length; counter++) {
            if (counts[counter] == max) {
                index = counter;
                break;
            }
        }
        //System.out.println("one majority class, index is: "+index);
        return uniqueValues[index];
    } else{//we have multiple modes
        int[] ix = new int[freq];//array of indices of modes
        System.out.println("multiple majority classes: "+freq+" classes");
        int ixi = 0;
        for (int counter = 0; counter < counts.length; counter++) {
            if (counts[counter] == max) {
                ix[ixi] = counter;//save index of each max count value
                ixi++; // increase index of ix array
            }
        }

        for (int counter = 0; counter < ix.length; counter++)         
            System.out.println("class index: "+ix[counter]);       

        //now choose one at random
        Random generator = new Random();        
        //get random number 0 <= rIndex < size of ix
        int rIndex = generator.nextInt(ix.length);
        System.out.println("random index: "+rIndex);
        int nIndex = ix[rIndex];
        //return unique value at that index 
        return uniqueValues[nIndex];
    }

}



private static double meanOfArray(double[] m) {
    double sum = 0.0;
    for (int j = 0; j < m.length; j++){
        sum += m[j];
    }
    return sum/m.length;
}






//simple class to model instances (features + class)
static class City { 
    double[] cityAttributes;
    String cityName;
    public City(double[] cityAttributes, String cityName){
        this.cityName = cityName;
        this.cityAttributes = cityAttributes;               
    }
}
//simple class to model results (distance + class)
static class Result {   
    double distance;
    String cityName;
    public Result(double distance, String cityName){
        this.cityName = cityName;
        this.distance = distance;               
    }
}
//simple comparator class used to compare results via distances
static class DistanceComparator implements Comparator<Result> {
    @Override
    public int compare(Result a, Result b) {
        return a.distance < b.distance ? -1 : a.distance == b.distance ? 0 : 1;
    }
}

}

错误:

 Exception in Application start method
 java.lang.reflect.InvocationTargetException
 at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
 at                           sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at      sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.jav     a:43)
 at java.lang.reflect.Method.invoke(Method.java:498)
 at           com.sun.javafx.application.LauncherImpl.launchApplicationWithArgs(LauncherImpl.j     ava:389)
 at      com.sun.javafx.application.LauncherImpl.launchApplication(LauncherImpl.java:328)
 at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.Comparator;
import java.util.HashSet;
import java.util.List;
import java.util.Random;
import java.util.Set;

import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.Label;
import javafx.scene.control.TextField;
import javafx.scene.layout.GridPane;
import javafx.stage.Stage;

public class Etst extends Application {

    @Override

    public void start(Stage primaryStage) {
        GridPane grid = new GridPane();
        // Labels & inputs Settings
        Label number1 = new Label("Data 1 :");
        Label number2 = new Label("Data 2 :");
        Label number3 = new Label("Data 3 :");
        Label number4 = new Label("Data 4 :");
        Label number5 = new Label("Data 5 :");
        Label resultat1 = new Label("The Result");
        TextField txt1 = new TextField();
        TextField txt2 = new TextField();
        TextField txt3 = new TextField();
        TextField txt4 = new TextField();
        TextField txt5 = new TextField();
        grid.add(number1, 0, 0);
        grid.add(number2, 0, 1);
        grid.add(number3, 0, 2);
        grid.add(number4, 0, 3);
        grid.add(number5, 0, 4);
        grid.add(resultat1, 0, 6);
        grid.add(txt1, 1, 0);
        grid.add(txt2, 1, 1);
        grid.add(txt3, 1, 2);
        grid.add(txt4, 1, 3);
        grid.add(txt5, 1, 4);
        Button butt = new Button();
        butt.setText("Applique KPPV");
        grid.add(butt, 0, 5);
        // My Main Method
        ///////////////////////////////////


        // ADDED THESE 5 LINES. NOW IT SHOWS A WINDOW WITH THESE VALUES FILLED IN
        txt1.setText("0.0");
        txt2.setText("0.0");
        txt3.setText("0.0");
        txt4.setText("0.0");
        txt5.setText("0.0");

        double insertedInt = Double.parseDouble(txt1.getText());
        double insertedInt2 = Double.parseDouble(txt2.getText());
        double insertedInt3 = Double.parseDouble(txt3.getText());
        double insertedInt4 = Double.parseDouble(txt4.getText());
        double insertedInt5 = Double.parseDouble(txt5.getText());
        double[] query = { insertedInt, insertedInt2, insertedInt3, insertedInt4, insertedInt5 };

        int k = 10;// K : Welaya List Counts
        List<City> cityList = new ArrayList<City>();
        List<Result> resultList = new ArrayList<Result>();
        cityList.add(new City(instances[0], "IRIS0"));
        cityList.add(new City(instances[1], "IRIS1"));
        cityList.add(new City(instances[2], "IRIS2"));
        cityList.add(new City(instances[3], "IRIS3"));
        cityList.add(new City(instances[4], "IRIS4"));
        cityList.add(new City(instances[5], "IRIS5"));
        cityList.add(new City(instances[6], "IRIS6"));
        cityList.add(new City(instances[7], "IRIS7"));
        cityList.add(new City(instances[8], "IRIS8"));
        cityList.add(new City(instances[9], "IRIS9"));
        // find distances
        for (City city : cityList) {
            double dist = 0.0;
            for (int j = 0; j < city.cityAttributes.length; j++) {
                dist += Math.pow(city.cityAttributes[j] - query[j], 2);
            }
            double distance = Math.sqrt(dist);
            resultList.add(new Result(distance, city.cityName));

        }

        Collections.sort(resultList, new DistanceComparator());
        String[] ss = new String[k];
        for (int x = 0; x < k; x++) {
            ss[x] = resultList.get(x).cityName;
        }
        String majClass = findMajorityClass(ss);
        // System.out.println("The Nearest IRIS Class is : "+majClass);

        ///////////////////////////////////
        Scene scene = new Scene(grid, 300, 250);

        // Final Action
        butt.setOnAction(event -> {
            resultat1.setText(majClass);
        });
        primaryStage.setTitle("KNN With JDK");
        primaryStage.setScene(scene);
        primaryStage.show();

    }

    /**
     * @param args
     *            the command line arguments
     */
    public static void main(String[] args) {
        launch(args);

    }

    // My Method
    // our Data Base
    static double[][] instances = { { 6.300000, 2.500000, 5.000000, 1.900000, 3.000000 },
            { 6.900000, 3.200000, 5.700000, 2.300000, 3.000000 }, { 5.100000, 3.800000, 1.900000, 0.400000, 1.000000 },
            { 6.600000, 2.900000, 4.600000, 1.300000, 2.000000 }, { 5.700000, 4.400000, 1.500000, 0.400000, 1.000000 },
            { 4.600000, 3.400000, 1.400000, 0.300000, 1.000000 }, { 4.300000, 3.000000, 1.100000, 0.100000, 1.000000 },
            { 6.900000, 3.100000, 5.100000, 2.300000, 3.000000 }, { 5.100000, 3.700000, 1.500000, 0.400000, 1.000000 },
            { 6.100000, 2.800000, 4.700000, 1.200000, 2.000000 },

    };

    private static String findMajorityClass(String[] array) {
        // add the String array to a HashSet to get unique String values
        Set<String> h = new HashSet<String>(Arrays.asList(array));
        // convert the HashSet back to array
        String[] uniqueValues = h.toArray(new String[0]);
        // counts for unique strings
        int[] counts = new int[uniqueValues.length];
        // loop thru unique strings and count how many times they appear in
        // origianl array
        for (int i = 0; i < uniqueValues.length; i++) {
            for (int j = 0; j < array.length; j++) {
                if (array[j].equals(uniqueValues[i])) {
                    counts[i]++;
                }
            }
        }

        for (int i = 0; i < uniqueValues.length; i++)
            System.out.println(uniqueValues[i]);
        for (int i = 0; i < counts.length; i++)
            System.out.println(counts[i]);

        int max = counts[0];
        for (int counter = 1; counter < counts.length; counter++) {
            if (counts[counter] > max) {
                max = counts[counter];
            }
        }
        System.out.println("max # of occurences: " + max);
        int freq = 0;
        for (int counter = 0; counter < counts.length; counter++) {
            if (counts[counter] == max) {
                freq++;
            }
        }
        int index = -1;
        if (freq == 1) {
            for (int counter = 0; counter < counts.length; counter++) {
                if (counts[counter] == max) {
                    index = counter;
                    break;
                }
            }
            // System.out.println("one majority class, index is: "+index);
            return uniqueValues[index];
        } else {// we have multiple modes
            int[] ix = new int[freq];// array of indices of modes
            System.out.println("multiple majority classes: " + freq + " classes");
            int ixi = 0;
            for (int counter = 0; counter < counts.length; counter++) {
                if (counts[counter] == max) {
                    ix[ixi] = counter;// save index of each max count value
                    ixi++; // increase index of ix array
                }
            }

            for (int counter = 0; counter < ix.length; counter++)
                System.out.println("class index: " + ix[counter]);

            // now choose one at random
            Random generator = new Random();
            // get random number 0 <= rIndex < size of ix
            int rIndex = generator.nextInt(ix.length);
            System.out.println("random index: " + rIndex);
            int nIndex = ix[rIndex];
            // return unique value at that index
            return uniqueValues[nIndex];
        }

    }

    private static double meanOfArray(double[] m) {
        double sum = 0.0;
        for (int j = 0; j < m.length; j++) {
            sum += m[j];
        }
        return sum / m.length;
    }

    // simple class to model instances (features + class)
    static class City {
        double[] cityAttributes;
        String cityName;

        public City(double[] cityAttributes, String cityName) {
            this.cityName = cityName;
            this.cityAttributes = cityAttributes;
        }
    }

    // simple class to model results (distance + class)
    static class Result {
        double distance;
        String cityName;

        public Result(double distance, String cityName) {
            this.cityName = cityName;
            this.distance = distance;
        }
    }

    // simple comparator class used to compare results via distances
    static class DistanceComparator implements Comparator<Result> {
        @Override
        public int compare(Result a, Result b) {
            return a.distance < b.distance ? -1 : a.distance == b.distance ? 0 : 1;
        }
    }

}

我只是设置了文本字段的初始文本,因此它不会引发错误。这不是一个好的编程风格,因为你混合了图形用户界面和业务逻辑。也许你应该重构你的整个程序