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Given 3 classes (Sweater, Jacket, and Vest), Sweater can inherit from both Jacket and Vest with the following syntax: public class Sweater extends Jacket, Vest {     /* valid class definition */ }

Given the following class hierarchy, identify whether the method explore is overloaded, overridden, or neither by the subclass: public class Traveler {    public void explore(String place, String name) { /* implemented */ }}public class Hiker extends Traveler {    public void explore(String n, String p) { /* implemented */ }}

Given 3 classes (Sweater, Jacket, and Vest), Sweater can inherit from both Jacket and Vest with the following syntax: public class Sweater extends Jacket, Vest {     /* valid class definition */ }

Analyze the following code and indicate, for each line, whether autoboxing, unboxing, or neither occurs when the assignment operator is evaluated: char c = new Character(‘b’); //  1   occursCharacter a = c; //  2   occurs   1   : [1]   2   : [2]

You have files Parent.java, Child.java, and a driver class named Driver.java. Fill in the correct visibility modifiers so that the comments in the class Child and Driver’s main method are upheld. public class Parent {   1 void method1() { /*compiles*/ }   2 void method2() { /*compiles*/ }   3 void method3() { /*compiles*/ } } —– in a separate file in a different package/directory —– public class Child extends Parent {   public void foo() { method2(); // doesn’t compile method3(); // compiles }} —– in a separate file in a different package/directory —– public class Driver { public static void main(String[] args) { Child c = new Child(); c.method1(); // compiles c.method2(); // doesn’t compile c.method3(); // doesn’t compile }}   1   : [1]  2   : [2]  3   : [3]

Car c1 = new Ford();Car c2 = new Honda();Ford f = new Ford();Honda h = new Honda(); For the class hierarchy and declarations above, correctly indicate whether each of the following statements will compile and what will happen at runtime (runs correctly or runtime exception). It may be helpful to use scratch paper to keep track of each variable’s static and dynamic type. 1  Car carA = (Car) f; 2   Ford fordA = (Ford) c1; 3  Ford fordB = (Ford) c2; 4  Ford fordC = (Ford) h;   1   : [1]  2   : [2]  3   : [3]  4   : [4]

Can you see Buzz between the lines? If not, let us know ASAP!   

Analyze the following code and indicate, for each line, whether autoboxing, unboxing, or neither occurs when the assignment operator is evaluated: int a = new Integer(5); //  1   occursInteger b = a; //  2   occurs   1   : [1]   2   : [2]

Analyze the following code and indicate, for each line, whether autoboxing, unboxing, or neither occurs when the assignment operator is evaluated: int a = new Integer(5); //  1   occursInteger b = a; //  2   occurs   1   : [1]   2   : [2]

   Avatar a1 = new Earth(); Avatar a2 = new Fire(); Earth e = new Earth(); Fire f = new Fire();  For the class hierarchy and declarations above, correctly indicate whether each of the following statements will compile and what will happen at runtime (runs correctly or runtime exception). It may be helpful to use scratch paper to keep track of each variable’s static and dynamic type. 1  Avatar avatar = (Avatar) f; 2   Fire f1 = (Fire) a1;  3  Fire f2 = (Fire) a2; 4  Fire f3 = (Fire) e;   1   : [1]  2   : [2]  3   : [3]  4   : [4]