Some computer science concept questions:
a. What is an object?
b. What is a class?
c. What is a type? Why are types important?
d. What is casting? What is it used for?
e. What is a variable? What are the differences between object variables and primitive variables?
f. What is garbage collection?
g. What are relational operators? What are math operators?
h. What is a string?
a. Objects are the persons, places, or things that do the action in a situation or are acted upon.
b. The way we classify objects or the type of the object. A class tells Java what data we expect objects of the class to have and what things objects can do.
c. The type of something in Java tells the computer how much space to allocate for the variable or object and how to treat the contents of the space. Variables declared as primitive types allocate space based on the type and set the value in that space to the
value of the variable. Variables declared as object types allocate space for a reference to an object. A reference is a way to find the object in memory.
d. Casting tells the compiler to change the type of the item to the specified type. One use of casting is to get the result of an integer expression in a double form.
e. A variable is a named memory location. When do you
need one? You need a variable when you want to remember a value or keep a reference to an object. Object variables are references to objects while primitive variables store values.
f. Garbage collection frees memory that has been allocated when it is no longer being used.
g. Relational operators are ways to test the relation between two numbers. You can check if numbers are greater-than, less-than equal or not equal. You can test combinations of these as well. Math operators include addition, subtraction, division, multiplication, negation, and remainder.
h. Java a string is an object that has a sequence of characters.
You might also like to view...
To draw a polygon, you pass to the method:
a) a brush or pen b) an array of points c) a brush or pen, and an array of points d) a grid with a list of points drawn on it
Answer the following statements true (T) or false (F)
1. If you set a group box control’s Visible property to False, the attached controls will still remain visible. 2. When a check box control has the focus, the spacebar can be used to invoke its CheckedChanged event. 3. As with the button and check box controls, an access key can be set up by placing an ampersand in front of a letter in the radio button’s Text property setting. 4. Suppose a form contains two group box controls with one radio button placed on each. In this case, both radio buttons can be selected (or turned “on”) at the same time.
Organizations invest heavily in information systems to improve customer service.
Answer the following statement true (T) or false (F)
Wide area networks share a few characteristics with local area networks.
Answer the following statement true (T) or false (F)