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//: generics/Apply.java

package generics; /* Added by Eclipse.py */

// {main: ApplyTest}

import java.lang.reflect.*;

import java.util.*;

import static net.mindview.util.Print.*;

public class Apply {

public static <T, S extends Iterable<? extends T>>

void apply(S seq, Method f, Object... args) {

try {

for(T t: seq)

f.invoke(t, args);

} catch(Exception e) {

// Failures are programmer errors

throw new RuntimeException(e);

}

}

}

class Shape {

public void rotate() { print(this + " rotate"); }

public void resize(int newSize) {

print(this + " resize " + newSize);

}

}

class Square extends Shape {}

class FilledList<T> extends ArrayList<T> {

public FilledList(Class<? extends T> type, int size) {

try {

for(int i = 0; i < size; i++)

// Assumes default constructor:

add(type.newInstance());

} catch(Exception e) {

throw new RuntimeException(e);

}

}

}

class ApplyTest {

public static void main(String[] args) throws Exception {

List<Shape> shapes = new ArrayList<Shape>();

for(int i = 0; i < 10; i++)

shapes.add(new Shape());

Apply.apply(shapes, Shape.class.getMethod("rotate"));

Apply.apply(shapes,

Shape.class.getMethod("resize", int.class), 5);

List<Square> squares = new ArrayList<Square>();

for(int i = 0; i < 10; i++)

squares.add(new Square());

Apply.apply(squares, Shape.class.getMethod("rotate"));

Apply.apply(squares,

Shape.class.getMethod("resize", int.class), 5);

Apply.apply(new FilledList<Shape>(Shape.class, 10),

Shape.class.getMethod("rotate"));

Apply.apply(new FilledList<Shape>(Square.class, 10),

Shape.class.getMethod("rotate"));

SimpleQueue<Shape> shapeQ = new SimpleQueue<Shape>();

for(int i = 0; i < 5; i++) {

shapeQ.add(new Shape());

shapeQ.add(new Square());

}

Apply.apply(shapeQ, Shape.class.getMethod("rotate"));

}

} /* (Execute to see output) *///:~