WeatherData.java

package ObserverPattern.JavaBuiltInExample;

import java.beans.PropertyChangeListener;
import java.beans.PropertyChangeSupport;

public class WeatherData {
    private final PropertyChangeSupport pcs = new PropertyChangeSupport(this);
    private float temperature;
    private float humidity;
    private float pressure;

    public WeatherData() {
    }

    public void addPropertyChangeListener(PropertyChangeListener listener) {
        pcs.addPropertyChangeListener(listener);
    }

    public void removePropertyChangeListener(PropertyChangeListener listener) {
        pcs.removePropertyChangeListener(listener);
    }

    public void measurementsChanged() {
        pcs.firePropertyChange("measurements", null, this);
    }

    public void setMeasurements(float temperature, float humidity, float pressure) {
        this.temperature = temperature;
        this.humidity = humidity;
        this.pressure = pressure;
        measurementsChanged();
    }

    public float getTemperature() {
        return temperature;
    }

    public float getHumidity() {
        return humidity;
    }

    public float getPressure() {
        return pressure;
    }
}