java语言的科学与艺术-编程练习7.4

import java.lang.Runtime;
import acm.program.*;
public class GCTest extends ConsoleProgram {
public void run() {
Runtime myRuntime = Runtime.getRuntime();
long oldMemory = myRuntime.freeMemory();
for(int i = 0; i < 10000; i++){
new Rational(1);
}
myRuntime.gc();
long newMemory = myRuntime.freeMemory();
long freeMemory = newMemory - oldMemory;
println("Allocating 10000 Rational objects");
println("Garbage collections freed " + freeMemory + " bytes");
}
}