Erreur "Could not instantiate bean class []: Constructor threw exception"

Bonjour,

Je suis en train de m'initier à Spring et donc j'ai créé un projet test.

Le problème est que j'obtiens cette exception à l'exécution :

Citation:

Could not instantiate bean class [monProg.maClasse]: Constructor threw exception;

Quelqu'un pourrait m'éclairer sur la manière de résoudre ce problème ?

Merci d'avance pour votre aide.

Bonjour,

Peut-on voir un peu plus sur les messages d'erreur? Les codes java et xml que tu as fait correspondants à la classe dite par l'erreur?

A+.

Voilà le message d'erreur :

Citation:

Exception in Application start method
java.lang.reflect.InvocationTargetException
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:601)
at com.javafx.main.Main.launchApp(Main.java:642)
at com.javafx.main.Main.main(Main.java:805)
Caused by: java.lang.RuntimeException: Exception in Application start method
at com.sun.javafx.application.LauncherImpl.launchApplication1(Unknown Source)
at com.sun.javafx.application.LauncherImpl.access$000(Unknown Source)
at com.sun.javafx.application.LauncherImpl$1.run(Unknown Source)
at java.lang.Thread.run(Thread.java:722)
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'clav' defined in class path resource [melordi/springXMLConfig.xml]: Instantiation of bean failed; nested exception is org.springframework.beans.BeanInstantiationException: Could not instantiate bean class [melordi.Clavier]: Constructor threw exception; nested exception is java.lang.NullPointerException
at org.springframework.beans.factory.support.ConstructorResolver.autowireConstructor(ConstructorResolver.java:288)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.autowireConstructor(AbstractAutowireCapableBeanFactory.java:1035)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:939)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:485)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:456)
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:294)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:225)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:291)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:193)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:585)
at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:913)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:464)
at org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:139)
at org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:83)
at melordi.MelOrdi.start(MelOrdi.java:27)
at com.sun.javafx.application.LauncherImpl$5.run(Unknown Source)
at com.sun.javafx.application.PlatformImpl$5.run(Unknown Source)
at com.sun.javafx.application.PlatformImpl$4.run(Unknown Source)
at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
at com.sun.glass.ui.win.WinApplication.access$100(Unknown Source)
at com.sun.glass.ui.win.WinApplication$3$1.run(Unknown Source)
... 1 more
Caused by: org.springframework.beans.BeanInstantiationException: Could not instantiate bean class [melordi.Clavier]: Constructor threw exception; nested exception is java.lang.NullPointerException
at org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:162)
at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:110)
at org.springframework.beans.factory.support.ConstructorResolver.autowireConstructor(ConstructorResolver.java:280)
... 21 more
Caused by: java.lang.NullPointerException
at melordi.Clavier.<init>(Clavier.java:62)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:525)
at org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:147)
... 23 more

Le code XML :
Code:

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 <?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:aop="http://www.springframework.org/schema/aop/spring-aop-2.5.xsd" xmlns:context="http://www.springframework.org/schema/context/spring-context-2.5.xsd" xmlns:lang="http://www.springframework.org/schema/lang/spring-lang-2.5.xsd" xmlns:util="http://www.springframework.org/schema/util/spring-util-2.5.xsd" xmlns:p="http://www.springframework.org/schema/p" xsi:schemaLocation="http://www.springframework.org/schema/beans <a href="http://www.springframework.org/schema/beans/spring-beans-2.5.xsd" target="_blank">http://www.springframework.org/schem...-beans-2.5.xsd</a> <a href="http://www.springframework.org/schema/aop/spring-aop-2.5.xsd" target="_blank">http://www.springframework.org/schem...ng-aop-2.5.xsd</a> <a href="http://www.springframework.org/schema/aop/spring-aop-2.5.xsd/spring-spring-aop-2.5.xsd-3.1.1.RELEASE.xsd" target="_blank">http://www.springframework.org/schem....1.RELEASE.xsd</a> <a href="http://www.springframework.org/schema/context/spring-context-2.5.xsd" target="_blank">http://www.springframework.org/schem...ontext-2.5.xsd</a> <a href="http://www.springframework.org/schema/context/spring-context-2.5.xsd/spring-spring-context-2.5.xsd-3.1.1.RELEASE.xsd" target="_blank">http://www.springframework.org/schem....1.RELEASE.xsd</a> <a href="http://www.springframework.org/schema/lang/spring-lang-2.5.xsd" target="_blank">http://www.springframework.org/schem...g-lang-2.5.xsd</a> <a href="http://www.springframework.org/schema/lang/spring-lang-2.5.xsd/spring-spring-lang-2.5.xsd-3.1.1.RELEASE.xsd" target="_blank">http://www.springframework.org/schem....1.RELEASE.xsd</a> <a href="http://www.springframework.org/schema/util/spring-util-2.5.xsd" target="_blank">http://www.springframework.org/schem...g-util-2.5.xsd</a> <a href="http://www.springframework.org/schema/util/spring-util-2.5.xsd/spring-spring-util-2.5.xsd-3.1.1.RELEASE.xsd" target="_blank">http://www.springframework.org/schem....1.RELEASE.xsd</a> "> <bean id="sound" class="melordi.SoundPlayer"> </bean> <bean id="metr" class="melordi.Metronome"> </bean> <bean id="change" class="melordi.ChangementSound"> <constructor-arg index="0" ref="sound"/> </bean> <bean id="clav" class="melordi.Clavier"> <constructor-arg index="0" ref="sound"/> <constructor-arg index="1" ref="metr"/> </bean> <bean id="vol" class="melordi.Volume"> <constructor-arg index="0" ref="clav"/> <constructor-arg index="1" ref="sound"/> </bean> <bean id="touch" class="melordi.Touche" scope="prototype"> <constructor-arg index="0" ref="sound"/> <constructor-arg index="1" ref="metr"/> <property name="haut" value="70"/> <property name="larg" value="70"/> </bean> </beans>
J'utilise JavaFX. La méthode start de la classe principale est comme suit :
Code:

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 public void start(Stage primaryStage) { primaryStage.setTitle("MelOrdi - Vamos la musica !"); appCtx = new ClassPathXmlApplicationContext("melordi/springXMLConfig.xml"); Group backGround = new Group(); Scene scene = new Scene(backGround, 500, 500, Color.WHITE); SoundPlayer instrument = appCtx.getBean("sound", SoundPlayer.class); Metronome metr = appCtx.getBean("metr", Metronome.class); backGround.getChildren().add(metr); Clavier monClavier = appCtx.getBean("clav", Clavier.class); backGround.getChildren().add(monClavier); ChangementSound change = appCtx.getBean("change", ChangementSound.class); backGround.getChildren().add(change); Volume volume = appCtx.getBean("vol", Volume.class); backGround.getChildren().add(volume); monClavier.setVol(volume); primaryStage.setScene(scene); primaryStage.show(); monClavier.requestFocus(); //transmission de la focalisation }
Enfin le classe qui crée l'erreur :
Code:

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 private SoundPlayer sound; private Volume vol; private Metronome metr; private ApplicationContext appCtx; public Clavier(SoundPlayer sound, Metronome metr){ this.sound = sound; this.metr = metr; Rectangle arriereClavier = new Rectangle(480, 200, Color.BLACK); arriereClavier.setArcHeight(30); arriereClavier.setArcWidth(30); arriereClavier.setFill( // ajout d'un dégradé new LinearGradient(0f, 0f, 0f, 1f, true, CycleMethod.NO_CYCLE, new Stop[] { new Stop(0, Color.web("#333333")), new Stop(1, Color.web("#000000")) } ) ); Reflection reflect = new Reflection(1, 0.25, 0, 0.5);// application d'un effet de réflection arriereClavier.setEffect(reflect); this.setTranslateX(10); this.setTranslateY(250); this.getChildren().add(arriereClavier); Touche touche = appCtx.getBean("touch", Touche.class); int var = -5; int dep = (int)(arriereClavier.getWidth() - (8 * (touche.getLarg() + 5))) / 2; for (int i = 0; i < 8; i++){ touches[i] = new Touche(notes[i], i * (touche.getLarg() + 5) + dep, 100 + var, sons[i], raccourcis[i], sound, metr); this.getChildren().add(touches[i]); var = - var; } this.setOnKeyPressed(new EventHandler<KeyEvent>(){ public void handle(KeyEvent ke) { if (ke.getCode().equals(KeyCode.UP)) { changeVolume(true); } if (ke.getCode().equals(KeyCode.DOWN)) { changeVolume(false); } for (Touche t : touches){ if (t.getRaccourci().toUpperCase().equals(ke.getText().toUpperCase())){ t.appui(); break; } } } }); this.setOnKeyReleased(new EventHandler<KeyEvent>(){ public void handle(KeyEvent ke) { for (Touche t : touches){ if (t.getRaccourci().toUpperCase().equals(ke.getText().toUpperCase())){ t.relachement(); break; } } } }); };

Citation:

Caused by: org.springframework.beans.BeanInstantiationException: Could not instantiate bean class [melordi.Clavier]: Constructor threw exception; nested exception is java.lang.NullPointerException

Il n'arrive pas à instancier la classe Clavier. Peut-on le voir?

A+.

Voilà la classe Clavier entière :

Code:

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
import javafx.event.EventHandler;
import javafx.scene.Parent;
import javafx.scene.effect.Reflection;
import javafx.scene.input.KeyCode;
import javafx.scene.input.KeyEvent;
import javafx.scene.paint.Color;
import javafx.scene.paint.CycleMethod;
import javafx.scene.paint.LinearGradient;
import javafx.scene.paint.Stop;
import javafx.scene.shape.Rectangle;
import org.springframework.context.ApplicationContext;
 
/**
 *
 * @author fnac
 */
public class Clavier extends Parent{
 
    private String[] notes = {"Do", "Ré", "Mi", "Fa", "Sol", "La", "Si", "Do"};
    private int[] sons = {60, 62, 64, 65, 67, 69, 71, 72};
    private Touche[] touches = new Touche[8];
    private String[] raccourcis = {"A", "Z", "E", "R", "T", "Y", "U", "I"};
    private SoundPlayer sound;
    private Volume vol;
    private Metronome metr;
 
    private ApplicationContext appCtx;
 
    public Clavier(SoundPlayer sound, Metronome metr){
 
        this.sound = sound;
        this.metr = metr;
 
        Rectangle arriereClavier = new Rectangle(480, 200, Color.BLACK);
        arriereClavier.setArcHeight(30);
        arriereClavier.setArcWidth(30);
 
        arriereClavier.setFill(                 // ajout d'un dégradé
            new LinearGradient(0f, 0f, 0f, 1f, true, CycleMethod.NO_CYCLE,
                new Stop[] {
                    new Stop(0, Color.web("#333333")),
                    new Stop(1, Color.web("#000000"))
                }
            )
        );
 
        Reflection reflect = new Reflection(1, 0.25, 0, 0.5);// application d'un effet de réflection
        arriereClavier.setEffect(reflect);
 
        this.setTranslateX(10);
        this.setTranslateY(250);
 
        this.getChildren().add(arriereClavier);
 
        Touche touche = appCtx.getBean("touch", Touche.class);
        int var = -5;
        int dep = (int)(arriereClavier.getWidth() - (8 * (touche.getLarg() + 5))) / 2;
        for (int i = 0; i < 8; i++){
            touches[i] = new Touche(notes[i], i * (touche.getLarg() + 5) + dep, 100 + var, sons[i], raccourcis[i], sound, metr);
            this.getChildren().add(touches[i]);
            var = - var;
        }
 
        this.setOnKeyPressed(new EventHandler<KeyEvent>(){
            public void handle(KeyEvent ke) {
                if (ke.getCode().equals(KeyCode.UP)) {
                    changeVolume(true);
                }
 
                if (ke.getCode().equals(KeyCode.DOWN)) {
                    changeVolume(false);
                }
 
                for (Touche t : touches){
                    if (t.getRaccourci().toUpperCase().equals(ke.getText().toUpperCase())){
                        t.appui();
                        break;
                    }
                }
            }
        });
 
        this.setOnKeyReleased(new EventHandler<KeyEvent>(){
            public void handle(KeyEvent ke) {
                for (Touche t : touches){
                    if (t.getRaccourci().toUpperCase().equals(ke.getText().toUpperCase())){
                        t.relachement();
                        break;
                    }
                }
            }
        });
    };
 
    public void setVol(Volume vol){
        this.vol = vol;
    }
 
    public void changeVolume(boolean up){
        if (up) {
            this.vol.slider.setValue(this.vol.slider.getValue() + 5);
        }
        else {
            this.vol.slider.setValue(this.vol.slider.getValue() - 5);
        }
    }
 
    public SoundPlayer getSound() {
        return sound;
    }
 
    public void setSound(SoundPlayer sound) {
        this.sound = sound;
    }
 
    public Metronome getMetr() {
        return metr;
    }
 
    public void setMetr(Metronome metr) {
        this.metr = metr;
    }
 
}

En fait, j'aimerais pouvoir définir les dimensions des objets dans le fichier XML et les récupérer comme paramètres dans mon code.
Mais puisque je ne trouve rien du genre "getProperty()", je veux passer par un bean mais je ne sais pas comment m'y prendre.