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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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package javafx.beans.property.adapter;

import com.sun.javafx.binding.ExpressionHelper;
import com.sun.javafx.property.MethodHelper;
import com.sun.javafx.property.adapter.Disposer;
import com.sun.javafx.property.adapter.PropertyDescriptor;
import javafx.beans.InvalidationListener;
import javafx.beans.property.FloatProperty;
import javafx.beans.value.ChangeListener;
import javafx.beans.value.ObservableValue;

import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.UndeclaredThrowableException;

import java.security.AccessControlContext;
import java.security.AccessController;
import java.security.PrivilegedAction;


A JavaBeanFloatProperty provides an adapter between a regular Java Bean property of type float or Float and a JavaFX FloatProperty. It cannot be created directly, but a JavaBeanFloatPropertyBuilder has to be used. 
 As a minimum, the Java Bean class must implement a getter and a setter for the property. The class, as well as the getter and a setter methods, must be declared public. If the getter of an instance of this class is called, the property of the Java Bean is returned. If the setter is called, the value will be passed to the Java Bean property. If the Java Bean property is bound (i.e. it supports PropertyChangeListeners), this JavaBeanFloatProperty will be aware of changes in the Java Bean. Otherwise it can be notified about changes by calling fireValueChangedEvent(). If the Java Bean property is also constrained (i.e. it supports VetoableChangeListeners), this JavaBeanFloatProperty will reject changes, if it is bound to an ObservableValue<Float>. 


Deploying an Application as a Module


 If the Java Bean class is in a named module, then it must be reflectively accessible to the javafx.base module. A class is reflectively accessible if the module opens the containing package to at least the javafx.base module. 


 For example, if com.foo.MyBeanClass is in the foo.app module, the module-info.java might look like this: 


module foo.app {
opens com.foo to javafx.base;



 Alternatively, a class is reflectively accessible if the module exports the containing package unconditionally. 


See Also:
Since:JavaFX 2.1
/**
 * A {@code JavaBeanFloatProperty} provides an adapter between a regular
 * Java Bean property of type {@code float} or {@code Float} and a JavaFX
 * {@code FloatProperty}. It cannot be created directly, but a
 * {@link JavaBeanFloatPropertyBuilder} has to be used.
 * <p>
 * As a minimum, the Java Bean class must implement a getter and a setter for the
 * property.
 * The class, as well as the getter and a setter methods, must be declared public.
 * If the getter of an instance of this class is called, the property of
 * the Java Bean is returned. If the setter is called, the value will be passed
 * to the Java Bean property. If the Java Bean property is bound (i.e. it supports
 * PropertyChangeListeners), this {@code JavaBeanFloatProperty} will be
 * aware of changes in the Java Bean. Otherwise it can be notified about
 * changes by calling {@link #fireValueChangedEvent()}. If the Java Bean property
 * is also constrained (i.e. it supports VetoableChangeListeners), this
 * {@code JavaBeanFloatProperty} will reject changes, if it is bound to an
 * {@link javafx.beans.value.ObservableValue ObservableValue&lt;Float&gt;}.
 * </p>
 * <p><b>Deploying an Application as a Module</b></p>
 * <p>
 * If the Java Bean class is in a named module, then it must be reflectively
 * accessible to the {@code javafx.base} module.
 * A class is reflectively accessible if the module
 * {@link Module#isOpen(String,Module) opens} the containing package to at
 * least the {@code javafx.base} module.
 * </p>
 * <p>
 * For example, if {@code com.foo.MyBeanClass} is in the {@code foo.app} module,
 * the {@code module-info.java} might
 * look like this:
 * </p>
 *
<pre>{@code module foo.app {
    opens com.foo to javafx.base;
}}</pre>
 *
 * <p>
 * Alternatively, a class is reflectively accessible if the module
 * {@link Module#isExported(String) exports} the containing package
 * unconditionally.
 * </p>
 *
 * @see javafx.beans.property.FloatProperty
 * @see JavaBeanFloatPropertyBuilder
 * @since JavaFX 2.1
 */
public final class JavaBeanFloatProperty extends FloatProperty implements JavaBeanProperty<Number> {

    private final PropertyDescriptor descriptor;
    private final PropertyDescriptor.Listener<Number> listener;

    private ObservableValue<? extends Number> observable = null;
    private ExpressionHelper<Number> helper = null;

    private final AccessControlContext acc = AccessController.getContext();

    JavaBeanFloatProperty(PropertyDescriptor descriptor, Object bean) {
        this.descriptor = descriptor;
        this.listener = descriptor.new Listener<Number>(bean, this);
        descriptor.addListener(listener);
        Disposer.addRecord(this, new DescriptorListenerCleaner(descriptor, listener));
    }

    
{@inheritDoc}

Throws:
  • UndeclaredThrowableException – if calling the getter of the Java Bean property throws an IllegalAccessException or an InvocationTargetException.
/**
     * {@inheritDoc}
     *
     * @throws UndeclaredThrowableException if calling the getter of the Java Bean
     * property throws an {@code IllegalAccessException} or an
     * {@code InvocationTargetException}.
     */
    @Override
    public float get() {
        return AccessController.doPrivileged((PrivilegedAction<Float>) () -> {
            try {
                return ((Number)MethodHelper.invoke(
                    descriptor.getGetter(), getBean(), (Object[])null)).floatValue();
            } catch (IllegalAccessException e) {
                throw new UndeclaredThrowableException(e);
            } catch (InvocationTargetException e) {
                throw new UndeclaredThrowableException(e);
            }
        }, acc);
    }

    
{@inheritDoc}

Throws:
  • UndeclaredThrowableException – if calling the getter of the Java Bean property throws an IllegalAccessException or an InvocationTargetException.
/**
     * {@inheritDoc}
     *
     * @throws UndeclaredThrowableException if calling the getter of the Java Bean
     * property throws an {@code IllegalAccessException} or an
     * {@code InvocationTargetException}.
     */
    @Override
    public void set(final float value) {
        if (isBound()) {
            throw new RuntimeException("A bound value cannot be set.");
        }
        AccessController.doPrivileged((PrivilegedAction<Void>) () -> {
            try {
                MethodHelper.invoke(descriptor.getSetter(), getBean(), new Object[] {value});
                ExpressionHelper.fireValueChangedEvent(helper);
            } catch (IllegalAccessException e) {
                throw new UndeclaredThrowableException(e);
            } catch (InvocationTargetException e) {
                throw new UndeclaredThrowableException(e);
            }
            return null;
        }, acc);
    }

    
{@inheritDoc}

/**
     * {@inheritDoc}
     */
    @Override
    public void bind(ObservableValue<? extends Number> observable) {
        if (observable == null) {
            throw new NullPointerException("Cannot bind to null");
        }

        if (!observable.equals(this.observable)) {
            unbind();
            set(observable.getValue().floatValue());
            this.observable = observable;
            this.observable.addListener(listener);
        }
    }

    
{@inheritDoc}

/**
     * {@inheritDoc}
     */
    @Override
    public void unbind() {
        if (observable != null) {
            observable.removeListener(listener);
            observable = null;
        }
    }

    
{@inheritDoc}

/**
     * {@inheritDoc}
     */
    @Override
    public boolean isBound() {
        return observable != null;
    }

    
{@inheritDoc}

/**
     * {@inheritDoc}
     */
    @Override
    public Object getBean() {
        return listener.getBean();
    }

    
{@inheritDoc}

/**
     * {@inheritDoc}
     */
    @Override
    public String getName() {
        return descriptor.getName();
    }

    
{@inheritDoc}

/**
     * {@inheritDoc}
     */
    @Override
    public void addListener(ChangeListener<? super Number> listener) {
        helper = ExpressionHelper.addListener(helper, this, listener);
    }

    
{@inheritDoc}

/**
     * {@inheritDoc}
     */
    @Override
    public void removeListener(ChangeListener<? super Number> listener) {
        helper = ExpressionHelper.removeListener(helper, listener);
    }

    
{@inheritDoc}

/**
     * {@inheritDoc}
     */
    @Override
    public void addListener(InvalidationListener listener) {
        helper = ExpressionHelper.addListener(helper, this, listener);
    }

    
{@inheritDoc}

/**
     * {@inheritDoc}
     */
    @Override
    public void removeListener(InvalidationListener listener) {
        helper = ExpressionHelper.removeListener(helper, listener);
    }

    
{@inheritDoc}

/**
     * {@inheritDoc}
     */
    @Override
    public void fireValueChangedEvent() {
        ExpressionHelper.fireValueChangedEvent(helper);
    }

    
{@inheritDoc}

/**
     * {@inheritDoc}
     */
    @Override
    public void dispose() {
        descriptor.removeListener(listener);

    }

    
Returns a string representation of this JavaBeanFloatProperty object. 
Returns:a string representation of this JavaBeanFloatProperty object.
/**
     * Returns a string representation of this {@code JavaBeanFloatProperty} object.
     * @return a string representation of this {@code JavaBeanFloatProperty} object.
     */
    @Override
    public String toString() {
        final Object bean = getBean();
        final String name = getName();
        final StringBuilder result = new StringBuilder("FloatProperty [");
        if (bean != null) {
            result.append("bean: ").append(bean).append(", ");
        }
        if ((name != null) && (!name.equals(""))) {
            result.append("name: ").append(name).append(", ");
        }
        if (isBound()) {
            result.append("bound, ");
        }
        result.append("value: ").append(get());
        result.append("]");
        return result.toString();
    }
}