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Chapter 8 Objects and Classes 1. See the section Declaring and Creating Objects. 2. Constructors are special kinds of methods that are called when creating an object using the new operator. Constructors do not have a return type—not even void. An array is an object. The default value for the elements of an array is 0 for numeric, false for boolean, ‘\u0000’ for char, null for object element type. a There is such constructor ShowErrors int in the ShowErrors class. The ShowErrors class in the book has a default constructor. It is actually same as public class ShowErrors public static void main String[] args ShowErrors t new ShowErrors 5 ; public ShowErrors On Line 3, new ShowErrors 5 attempts to create an instance using a constructor ShowErrors int , but the ShowErrors class does not have such a constructor. That is an error. b x is not a method in the ShowErrors class. The ShowErrors class in the book has a default constructor. It is actually same as public class ShowErrors public static void main String[] args ShowErrors t new ShowErrors ; t.x ; public ShowErrors On Line 4, t.x is invoked, but the ShowErrors class does not have the method named x . That is an error. c The program compiles fine, but it has a runtime error because variable c is null when the println statement is executed. d new C 5.0 does not match any constructors in class C. The program has a compilation error because class C does not have a constructor with a double argument. The program does not compile because new A is used in class Test, but class A does not have a default constructor. See the second NOTE in the Section, “Constructors.” false Use the Date’s no-arg constructor to create a Date for the current time. Use the Date’s toString method to display a string representation for the Date. Use the JFrame’s no-arg constructor to create JFrame. Use the setTitle String method a set a title and use the setVisible true method to display the frame. Date is in java.util.