Java - Chapter 7 - 8

The following logical expression illustrates what concept?
!( A || B) = !A && !B

• DeMorgan's Theorem
• Short-circuiting
• Mathematical expression
• flow control

What is the difference between the "==" and "=" operators?

• "==" tests for equality, "=" is an assignment
• "=" tests for equality, "==" is an assignment
• "==" is used on strings, while "=" is used on numbers

Which of the following expressions is the most effective way to compare the contents of two strings in myString1 and myString2 variables?

• myString1.equals(myString2)
• myString1 == myString2
• Both of these work equally well
• Neither of these will work

Using the rules of operator precedence, what is the result of the following equation?
int result = 2 + 4 / 1 * 3 - 1;

• 13
• 17
• 12
• Impossible to tell without parentheses

If "A" is true, short-circuiting would prevent the "B" expression from being evaluated in this
overall expression: if ( A || B )

• True
• False

What is the effect of using the equals operator == to compare two reference values?

• You will find out if the two values refer to exactly the same object in memory
• You will find out if the two objects contain essentially the same data
• You will get a compile-time syntax error because you must always use the equals() method to compare
  reference values
• You may get a run-time exception if the two objects are not identical 0

When using an if() statement, what must go within the parentheses?

• A logical expression
• A mathematical expression
• A mathematical expression
  A string
• An else clause

What will be printed to the screen after the following statements execute?
if (false)
System.out.print("1");
System.out.print("2");

• 2
• 12
• 21
• nothing

How many "else if ()" clauses can you have after an if() expression?

• 0, 1, or more
• 1 only
• 0
• Up to 3

Which of the following expressions are valid?

• if (6 + 3 > 5)
• if (6 + 3)
• if (6 + 3 = 5)
• They are all valid if() expressions