编程思想14章总结及习题答案

package basic;
interface A1401{ }
interface B1401{}
interface C1401{}
class Toy{
    //public Toy(){
   // }
    public Toy(int i){
    }
}
class FancyToy extends Toy implements A1401,B1401,C1401{
    public FancyToy(){
        super(1);
    }
}
public class Test1401 {
    static void printInfo(Class cc){
        System.out.println("Class name" + cc.getName() + "is interface ? [ "+ cc.isInterface() +"]"  );
        System.out.println("Class simplename :" + cc.getSimpleName());
        System.out.println("Class canonical name :" + cc.getCanonicalName());
    }
    public static void main(String[] args) {
        Class c = null;
        try {
            c = Class.forName("basic.FancyToy");
        } catch (ClassNotFoundException e) {
            System.out.println("catch not find");
            System.exit(1);
        }
        printInfo(c);
        for (Class inter: c.getInterfaces()
        ){
            printInfo(inter);
        }
        Object obj = null;
        Class superclass = c.getSuperclass();
        try {
            obj = superclass.newInstance();
        } catch (InstantiationException e) {
            e.printStackTrace();
        } catch (IllegalAccessException e) {
            e.printStackTrace();
        }
        printInfo(obj.getClass());
    }
}

Class namebasic.FancyToyis interface ? [ false]
java.lang.InstantiationException: basic.Toy
Class simplename :FancyToy
  at java.lang.Class.newInstance(Class.java:427)
Class canonical name :basic.FancyToy
Class namebasic.A1401is interface ? [ true]
  at basic.Test1401.main(Test1401.java:42)
Class simplename :A1401
Class canonical name :basic.A1401
Caused by: java.lang.NoSuchMethodException: basic.Toy.<init>()
Class namebasic.B1401is interface ? [ true]
  at java.lang.Class.getConstructor0(Class.java:3082)
Class simplename :B1401
  at java.lang.Class.newInstance(Class.java:412)
Class canonical name :basic.B1401
  ... 1 more
Class namebasic.C1401is interface ? [ true]
Class simplename :C1401
Exception in thread "main" java.lang.NullPointerException
Class canonical name :basic.C1401
  at basic.Test1401.main(Test1401.java:48)
Process finished with exit code 1