多选题In which two cases does the compiler supply a default constructor for class A?()Aclass A{}Bclass A { public A(){} }Cclass A { public A(int x){} }Dclass Z {} class A extends Z { void A(){} }
多选题
In which two cases does the compiler supply a default constructor for class A?()
A
class A{}
B
class A { public A(){} }
C
class A { public A(int x){} }
D
class Z {} class A extends Z { void A(){} }
参考解析
解析:
暂无解析
相关考题:
单选题1. public class Test { 2. int x= 12; 3. public void method(int x) { 4. x+=x; 5. System.out.println(x); 6. } 7. } Given: 34. Test t = new Test(); 35. t.method(5); What is the output from line 5 of the Test class?()A 5B 10C 12D 17E 24
单选题class Super { public int i = 0; public Super(String text) { i = 1; } } public class Sub extends Super { public Sub(String text) { i = 2; } public static void main(String args[]) { Sub sub = new Sub(“Hello”); System.out.println(sub.i); } } What is the result?()A 0B 1C 2D Compilation fails.
单选题A programmer needs to create a logging method that can accept an arbitrary number of arguments. For example, it may be called in these ways: logIt(”log message 1 “); logIt(”log message2”,”log message3”); logIt(”log message4”, “log message5”, “log message6); Which declaration satisfies this requirement?()A public void logIt(String * msgs)B public void logIt(String [] msgs)C public void logIt(String... msgs)D public void logIt(String msg1, String msg2, String msg3)
多选题Which two statements are true regarding the creation of a default constructor? ()AThe default constructor initializes method variables.BThe compiler always creates a default constructor for every class.CThe default constructor invokes the no-parameter constructor of the superclass.DThe default constructor initializes the instance variables declared in the class.EWhen a class has only constructors with parameters, the compiler does not create a default constructor.
单选题public class Score implements Comparable { private int wins, losses; public Score(int w, int 1) { wins = w; losses = 1; } public int getWins() { return wins; } public int getLosses() { return losses; } public String toString() { return “”; } // insert code here } Which method will complete this class?()A public int compareTo(Object o) {/*mode code here*/}B public int compareTo(Score other) {/*more code here*/}C public int compare(Score s1,Score s2){/*more code here*/}D public int compare(Object o1,Object o2){/*more code here*/}
多选题1. class TestA { 2. TestB b; 3. TestA() { 4. b = new TestB(this); 5. } 6. } 7. class TestB { 8. TestA a; 9. TestB(TestA a) { 10. this.a = a; 11. } 12. } 13. class TestAll { 14. public static void main (String args[]) { 15. new TestAll().makeThings(); 16. // ...code continues on 17. } 18. void makeThings() { 19. TestA test = new TestA(); 20. } 21. } Which two statements are true after line 15, before main completes?()ALine 15 causes a stack overflow.BAn exception is thrown at runtime.CThe object referenced by a is eligible for garbage collection.DThe object referenced by b is eligible for garbage collection.EThe object referenced by a is not eligible for garbage collection.FThe object referenced by b is not eligible for garbage collection.
多选题10. abstract public class Employee { 11. protected abstract double getSalesAmount(); 12. public double getCommision() { 13. return getSalesAmount() * 0.15; 14. } 15. } 16. class Sales extends Employee { 17. // insert method here 18. } Which two methods, inserted independently at line 17, correctly complete the Sales class?()Adouble getSalesAmount() { return 1230.45; }Bpublic double getSalesAmount() { return 1230.45; }Cprivate double getSalesAmount() { return 1230.45; }Dprotected double getSalesAmount() { return 1230.45; }
单选题You need to store elements in a collection that guarantees that no duplicates are stored and all elements can be accessed in natural order. Which interface provides that capability?()AJava.util.Map.BJava.util.Set.CJava.util.List.DJava.util.StoredSet.EJava.util.StoredMap.FJava.util.Collection.