Question

would someone please kind enough to help me out on my intro to java study guide by helping me with some useful tips/ examples or anything on these questions.

My grade is on the line and would really appreciate your help!

Final exam study guide

13. truncating vs rounding - Where do you encounter truncation? Where do you encounter rounding?
14. Can you identify the following items in a Java source code example (using just syntax, usage, and naming convention)?
Java reserved/keyword, primitive, array, object, class, named constant, literals (integer literal, floating point literal, character literal, string literal, Boolean literal), instance variable, void method, return method

15. Overloading - What is overloading? When is it valid for two methods to be overloaded?
16. When evaluating an expression, what are the three rules for order of operations?
17. List the operators (or their categories) in order of precedence.

Answer 1

13.

Truncating: In Java, truncating is referred as chopping of the decimal part of a number. For example, 5.8 can be truncated to 5.

Rounding: In Java, rounding is referred as rounding the decimal part of a number up to specified number of decimals. For example, rounding of 5.865 to two decimal places is 5.87.

Truncating is used whenever the decimal part needs to be excluded where as the concept of rounding is used to round the decimal part of a number up to certain decimals.

14.

Reserved / keyword: In Java, some words are reserved for certain functionality and they cannot be used as identifiers. For example, while, do, class, abstract etc.

Primitive: In Java, primitive types are the basic data types such as int, float, double, long, char, short, Boolean, byte. These are used for manipulating the dats.

For example, int d=5; char c=’A’; float num=3.564;

Array: Array holds the elements of similar type in contiguous locations.

For example, int arrElem[]={5,4,8};

Object: Object is a real-world entity. The objects share properties of a class.

For example, Dog t1=new Dog(); // t1 is the object of the class Dog.

Class: In Java, class is a blueprint which contains set of properties. The object of a class shares the properties of a class.

Named constant: The value of the named constant is permanent which cannot be changed during the execution of a program.

For example, final int num=4;

Literals: In Java, literals are syntactic representation of data. Various of Java literals are integer literal, floating point literal, character literal, string literal, Boolean literal. These are used to represent a fixed value.

Instance variable: The instance variable is created when the object is created. These variables can be accessed by calling the variables of the class.

Void method: Void is used as a return type for the method which returns nothing.

Return method: The method that returns some type of data is the return method. The return type may be int, float, double etc.

15.

Overloading: Overloading is a concept in which the class can have more than one method having the same name with different arguments.

This concept is valid if and only if there are more methods with same name having different arguments.

16.

The three rules while evaluating the expression are,

• First evaluate the operations within the parenthesis (if found).
• Next, perform all multiplication and division operations from left to right of the expression.
• After that, perform all addition and subtraction operations from left to right of the expression.

17.

In evaluating the expressions, order of precedence should be followed. The order of preference in Java is,

• The operators with in the Parenthesis
• postfix increment and decrement operators (++, --)
• prefix increment and decrement, and unary operators (++, --, +, -, ~, !)
• multiplicative operators (*, /, %)
• additive operators (+, -)
• shift operators (<<, >>, >>>)
• relational operators (<, >, <=, >=)
• equality operators (==, !=)
• bitwise AND operator (&)
• bitwise exclusive OR operator (^)
• bitwise inclusive OR operator (|)
• logical AND operator (&&)
• logical OR operator (||)
• ternary operator (? :)
• assignment operators (=, +=, -= etc.)