[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"$focstqe7xgZfcxgKOgM9TRZ7-ORqQyRpqvRimVRNd-vo":3},{"answer":4,"createTime":5,"id":6,"options":7,"origin":12,"question":19,"related":20,"source":30,"type":31},[],"2024-12-17 23:56:19",171917932,[8,9,10,11],"BA","BB","AB","AA",{"count":13,"courseId":14,"courseImg":15,"courseName":16,"workId":17,"workName":18},38,"3e98ca3bfe17bba47b43d97d3e082a44","https:\u002F\u002Ftihai-oss-cloud.itihey.com\u002Fimg\u002F9fdf9c3346a58e86cdf9bde73189de1e.jpg","JAVA编程技术","work_39585719","第7次作业20221201(zz老师)","下面程序运行结果( ) public class Alpha{ public void foo(){ System.out.print("A"); } } public class Beta extends Alpha{ public void foo(){ System.out.print("B"); } } public class test{ public static void main(String[] args){ Alpha a = new Beta(); Beta b = (Beta)a; a.foo(); b.foo(); }}",[21,32,41,50,59,67,70,75,84,93],{"answer":22,"createTime":5,"id":23,"options":24,"question":29,"source":30,"type":31},[],171917927,[25,26,27,28],"12","8","-12","Compilation fails","1. public class SimpleCalc{ 2. public int value; 3. public void calculate(){value += 7;} 4. } And: 1. public class MultiCalc extends SimpleCalc{ 2. public void calculate(){value -= 3;} 3. public void calculate(int multiplier){ 4. calculate(); 5. super.calculate(); 6. value *= multiplier; 7. } 8. public static void main(String[] args){ 9. MultiCalc calculator = new MultiCalc(); 10. calculator.calculate(2); 11. System.out.println("Value is: " + calculator.value); 12. } 13. } What is the result","v1",0,{"answer":33,"createTime":5,"id":34,"options":35,"question":40,"source":30,"type":31},[],171917928,[36,37,38,39],"3","5","4","6","下面接口声明1-7中,用法错误有几个( ) public interface A { 1. int var=1; 2. public A() { } 3. void method1() { } 4. protected void method2(); 5. static void method3(); 6. static void method4() { } 7. default void method5() { } }",{"answer":42,"createTime":5,"id":43,"options":44,"question":49,"source":30,"type":31},[],171917929,[45,46,47,48],"Foo f = (Delta)x","Foo f = (Alpha)x","Beta b = (Beta)(Alpha)x","Alpha a = x","10. interface Foo{ } 11. class Alpha implements Foo{ } 12. class Beta extends Alpha{ } 13. class Delta extends Beta{ 14. public static void main(String[ ] args){ 15. Beta x = new Beta(); 16. \u002F\u002Finsert code here 17. } 18. } Which code, inserted at line 16, will cause a java.lang.ClassCastException",{"answer":51,"createTime":5,"id":52,"options":53,"question":58,"source":30,"type":31},[],171917930,[54,55,56,57],"B b= new C( )","C x= new B( )","B b= new B( )","C x= C( )","B是一个抽象类,C是B的非抽象子类,下列创建对象x的语句中正确的是( )",{"answer":60,"createTime":5,"id":61,"options":62,"question":66,"source":30,"type":31},[],171917931,[28,63,64,65],"s 16","s 10","s 14","11.public interface A {12. public static final int EASY = 3;13. void doStuff(int t);14.}15.16.public class Test implements A {17. void doStuff(int s) {18. s += A.EASY + ++s;19. System.out.println("s " + s);20. }21. public static void main(String[] args) {22. int x = 5;23. new Test2().doStuff(++x);24. }35.}What is the result",{"answer":68,"createTime":5,"id":6,"options":69,"question":19,"source":30,"type":31},[],[8,9,10,11],{"answer":71,"createTime":5,"id":72,"options":73,"question":74,"source":30,"type":31},[],171917933,[8,9,11,10],"11. class Alpha{ 12. public void foo(){System.out.print("A");} 13. } 14. public class Beta extends Alpha{ 15. public void foo(){System.out.print("B");} 16. public static void main(String[ ] args){ 17. Alpha a = new Beta(); 18. Beta b = (Beta)a; 19. a.foo(); 20. b.foo(); 21. } 22. } What is the result",{"answer":76,"createTime":5,"id":77,"options":78,"question":83,"source":30,"type":31},[],171917934,[79,80,81,82],"public interface A implements C extends B { }","public interface A extends B { }","public class A implements C extends B { }","public class A extends B implements C, D { }","设B是类,C和D是接口,以下声明正确的是( )",{"answer":85,"createTime":5,"id":86,"options":87,"question":92,"source":30,"type":31},[],171917935,[88,89,90,91],"Compilation fails because of an error in line 5","Compilation fails because of an error in line 4","test","null","1. interface TestA{ String toString(); } 2. public class Test{ 3. public static void main(String[ ] args){ 4. System.out.println(new TestA(){ 5. public String toString(){return "test";} 6. }); 7. } 8. } What is the result",{"answer":94,"createTime":5,"id":95,"options":96,"question":101,"source":30,"type":31},[],171917936,[97,98,99,100],"Exactly one class does NOT compile","Exactly four class does NOT compile","Exactly three class does NOT compile","Exactly two class does NOT compile","11. public interface A{ public void m1(); } 13. class B implements A{ } 14. class C implements A{ public void m1(){ }} 15. class D implements A{ public void m1(int x){ }} 16. abstract class E implements A { } 17. abstract class F implements A { public void m1(){ } } 18. abstract class G implements A { public void m1(int x){ } } What is the result"]