Chapter 1

Question 1

Java identifier

Answer 1

A sequence of letters, digits, underscores, and dollar signs that must begin with either a letter or an underscore.

Question 2

keywords in Java

Answer 2

Certain identifiers reserved by Java

Question 3

Variable

Answer 3

Represents a memory location that contains a value of a primitive data type or a reference.

Question 4

How to declare a variable’s data type

Answer 4

You declare a variable’s data type by preceding the variable name with the data type, as in
double radius;
String name;

Question 5

What are the four categories of primitive data types in Java?

Answer 5

1. Boolean
2. Character
3. Integer
4. Floating Point

Question 6

Integral Types

Answer 6

Character and integer types (primitive types, that is)

Question 7

Arithmetic types

Answer 7

Integral and floating point types

Question 8

Integer values

Answer 8

These are signed and allow numbers such as -5 and +98.

Question 9

Floating-point Types

Answer 9

These provide for real numbers that have both an integer portion and a fractional portion.

Question 10

Wrapper class

Answer 10

Everything in Java is an object, except primitive data types. As a solution to this problem, Java allows you to include the primitives in the family of objects by using what are called wrapper classes.

Question 11

Autoboxing

Answer 11

Makes it easier to convert from a primitive type to their equivalent wrapper class counterparts.

Integer intObject = 9;

Question 12

Auto-unboxing

Answer 12

The reverse process of converting an object of one of the wrapper classes into a value of the corresponding primitive type.

Question 13

References in Java

Answer 13

Java has one other type that is used to locate an object. This reference variable contains an object’s location in memory.

Question 14

Literal constants

Answer 14

Indicate particular values within a program.
4 * Math.PI * radiusCubed / 3
(4 & 3 are literal constants)

Question 15

Backslash notation

Answer 15

This notation is useful when you want to embed one of these characters within a literal character string.

Question 16

Named constants

Answer 16

Have values that do not change. The declaration of a named constant is like that of a variable, but the keyword final precedes the data type.

Question 17

Assignment Statement

Answer 17

Assigns the value of an expression to a variable.

Question 18

What is an Array?

Answer 18

An array is a collection of elements, items, or values that have the same data type. Contains a finite, limited number of elements. Is direct, or random, access data structure.