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rickyclarkson/gist:382097

Created April 28, 2010 12:47
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gistfile1.txt
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import java.beans.PropertyChangeSupport;
import java.util.ArrayList;
import java.util.List;
class Main {
public static void main(String[] args) {
System.out.println("Version 1");
MutableComplex.main();
System.out.println("Version 2, changing double to float but not changing the PropertyChangeListener");
try {
MutableComplex2.main();
}
catch (ClassCastException e) {
e.printStackTrace();
}
System.out.println("Version 3, based on version 1 but dumping the PCListener in favour of types.");
MutableComplex3.main();
System.out.println("Version 4, based on version 3 but with the refactor from double to float.");
MutableComplex4.main();
}
}
class MutableComplex {
private double re, im;
public double re() { return re; }
public double im() { return im; }
private final PropertyChangeSupport support = new PropertyChangeSupport(this);
public static final String RE = "Re";
public static final String IM = "Im";
public void addPropertyChangeListener(PropertyChangeListener listener) {
support.addPropertyChangeListener(listener);
}
public void re(double re) {
support.firePropertyChange(RE, this.re, this.re = re);
}
public void im(double im) {
support.firePropertyChange(IM, this.im, this.im = im);
}
public static void main(String... args) {
MutableComplex complex = new MutableComplex();
complex.addPropertyChangeListener(new PropertyChangeListener() {
@Override
public void propertyChange(PropertyChangeEvent event) {
if (event.getPropertyName().equals(RE))
System.out.println(RE + " was changed by " +
((Double)event.getNewValue() - (Double)event.getOldValue()) + " units.");
}
});
complex.re(3);
complex.im(4);
complex.re(5);
}
}
class MutableComplex2 {
private float re, im;
public float re() { return re; }
public float im() { return im; }
private final PropertyChangeSupport support = new PropertyChangeSupport(this);
public static final String RE = "Re";
public static final String IM = "Im";
public void addPropertyChangeListener(PropertyChangeListener listener) {
support.addPropertyChangeListener(listener);
}
public void re(float re) {
support.firePropertyChange(RE, this.re, this.re = re);
}
public void im(float im) {
support.firePropertyChange(IM, this.im, this.im = im);
}
public static void main(String... args) {
MutableComplex2 complex = new MutableComplex2();
complex.addPropertyChangeListener(new PropertyChangeListener() {
@Override
public void propertyChange(PropertyChangeEvent event) {
if (event.getPropertyName().equals(RE))
System.out.println(RE + " was changed by " +
((Double)event.getNewValue() - (Double)event.getOldValue()) + " units.");
}
});
complex.re(3);
complex.im(4);
complex.re(5);
}
}
interface ChangeListener<T> {
void changed(T oldValue, T newValue);
}
final class Watch<T> {
private final List<ChangeListener<T>> listeners = new ArrayList<ChangeListener<T>>();
public void addListener(ChangeListener<T> listener) {
listeners.add(listener);
}
public void changed(T oldValue, T newValue) {
for (ChangeListener<T> listener: listeners)
listener.changed(oldValue, newValue);
}
}
class MutableComplex3 {
private double re, im;
public double re() { return re; }
public double im() { return im; }
public final Watch<Double> watchRe = new Watch<Double>();
public final Watch<Double> watchIm = new Watch<Double>();
public void re(double re) {
watchRe.changed(this.re, this.re = re);
}
public void im(double im) {
watchIm.changed(this.im, this.im = im);
}
public static void main(String... args) {
MutableComplex3 complex = new MutableComplex3();
complex.watchRe.addListener(new ChangeListener<Double>() {
@Override
public void changed(Double oldValue, Double newValue) {
System.out.println("Re was changed by " + (newValue - oldValue) + " units.");
}
});
complex.re(3);
complex.im(4);
complex.re(5);
}
}
class MutableComplex4 {
private float re, im;
public float re() { return re; }
public float im() { return im; }
public final Watch<Float> watchRe = new Watch<Float>();
public final Watch<Float> watchIm = new Watch<Float>();
public void re(float re) {
watchRe.changed(this.re, this.re = re);
}
public void im(float im) {
watchIm.changed(this.im, this.im = im);
}
public static void main(String... args) {
MutableComplex4 complex = new MutableComplex4();
complex.watchRe.addListener(new ChangeListener<Float>() {
@Override
public void changed(Float oldValue, Float newValue) {
System.out.println("Re was changed by " + (newValue - oldValue) + " units.");
}
});
complex.re(3);
complex.im(4);
complex.re(5);
}
}
@rickyclarkson
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import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import java.beans.PropertyChangeSupport;
import java.util.ArrayList;
import java.util.List;

class Main {
public static void main(String[] args) {
System.out.println("Version 1");
MutableComplex.main();
System.out.println("Version 2, changing double to float but not changing the PropertyChangeListener");
try {
MutableComplex2.main();
}
catch (ClassCastException e) {
e.printStackTrace();
}
System.out.println("Version 3, based on version 1 but dumping the PCListener in favour of types.");
MutableComplex3.main();
System.out.println("Version 4, based on version 3 but with the refactor from double to float.");
MutableComplex4.main();
}
}

class MutableComplex {
private double re, im;
public double re() { return re; }
public double im() { return im; }

private final PropertyChangeSupport support = new PropertyChangeSupport(this);
public static final String RE = "Re";
public static final String IM = "Im";

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

public void re(double re) {
support.firePropertyChange(RE, this.re, this.re = re);

}

public void im(double im) {
support.firePropertyChange(IM, this.im, this.im = im);
}

public static void main(String... args) {
MutableComplex complex = new MutableComplex();
complex.addPropertyChangeListener(new PropertyChangeListener() {
    @Override
    public void propertyChange(PropertyChangeEvent event) {
    if (event.getPropertyName().equals(RE))
        System.out.println(RE + " was changed by " + ((Double)event.getNewValue() - (Double)event.getOldValue()) + " units.");
    }
});
complex.re(3);
complex.im(4);
complex.re(5);
}

}

class MutableComplex2 {
private float re, im;
public float re() { return re; }
public float im() { return im; }

private final PropertyChangeSupport support = new PropertyChangeSupport(this);
public static final String RE = "Re";
public static final String IM = "Im";

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

public void re(float re) {
    support.firePropertyChange(RE, this.re, this.re = re);

}

public void im(float im) {
    support.firePropertyChange(IM, this.im, this.im = im);
}

public static void main(String... args) {
    MutableComplex2 complex = new MutableComplex2();
    complex.addPropertyChangeListener(new PropertyChangeListener() {
        @Override
    public void propertyChange(PropertyChangeEvent event) {
            if (event.getPropertyName().equals(RE))
                System.out.println(RE + " was changed by " + ((Double)event.getNewValue() - (Double)event.getOldValue()) + " units.");
        }
    });
    complex.re(3);
    complex.im(4);
    complex.re(5);
}

}

interface ChangeListener {
void changed(T oldValue, T newValue);
}

final class Watch {
private final List<ChangeListener> listeners = new ArrayList<ChangeListener>();

public void addListener(ChangeListener<T> listener) {
listeners.add(listener);
}

public void changed(T oldValue, T newValue) {
for (ChangeListener<T> listener: listeners)
    listener.changed(oldValue, newValue);
}

}

class MutableComplex3 {
private double re, im;
public double re() { return re; }
public double im() { return im; }

public final Watch<Double> watchRe = new Watch<Double>();
public final Watch<Double> watchIm = new Watch<Double>();

public void re(double re) {
watchRe.changed(this.re, this.re = re);

}

public void im(double im) {
watchIm.changed(this.im, this.im = im);
}

public static void main(String... args) {
MutableComplex3 complex = new MutableComplex3();
complex.watchRe.addListener(new ChangeListener<Double>() {
    @Override
        public void changed(Double oldValue, Double newValue) {
        System.out.println("Re was changed by " + (newValue - oldValue) + " units.");
    }
});
complex.re(3);
complex.im(4);
complex.re(5);
}

}

class MutableComplex4 {
private float re, im;
public float re() { return re; }
public float im() { return im; }

public final Watch<Float> watchRe = new Watch<Float>();
public final Watch<Float> watchIm = new Watch<Float>();

public void re(float re) {
watchRe.changed(this.re, this.re = re);

}

public void im(float im) {
watchIm.changed(this.im, this.im = im);
}

public static void main(String... args) {
MutableComplex4 complex = new MutableComplex4();
complex.watchRe.addListener(new ChangeListener<Float>() {
    @Override
        public void changed(Float oldValue, Float newValue) {
        System.out.println("Re was changed by " + (newValue - oldValue) + " units.");
    }
});
complex.re(3);
complex.im(4);
complex.re(5);
}

}

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