Here is an example of the way that the ? is employed:
ratio = denom == 0 ? 0 : num / denom;
When Java evaluates this assignment expression, it first looks at the expression to the left of
the question mark. If denom equals zero, then the expression between the question mark
and the colon is evaluated and used as the value of the entire ? expression. If denom does
not equal zero, then the expression after the colon is evaluated and used for the value of the
entire ? expression. The result produced by the ? operator is then assigned to ratio.

The switch statement works like this: The value of the expression is compared with each of
the values in the case statements. If a match is found, the code sequence following that case
statement is executed. If none of the constants matches the value of the expression, then the
default statement is executed. However, the default statement is optional. If no case matches
and no default is present, then no further action is taken.
The break statement is used inside the switch to terminate a statement sequence. When a
break statement is encountered, execution branches to the first line of code that follows the
entire switch statement. This has the effect of “jumping out” of the switch.

class MissingBreak {
public static void main(String args[]) {
for(int i=0; i<12; i++)
switch(i) {
case 0:
case 1:
case 2:
case 3:
case 4:
System.out.println(“i is less than 5”);
case 5:
case 6:
case 7:
case 8:
case 9:
System.out.println(“i is less than 10”);
System.out.println(“i is 10 or more”);

switch(count) {
case 1:
switch(target) { // nested switch
case 0:
System.out.println(“target is zero”);
case 1: // no conflicts with outer switch
System.out.println(“target is one”);


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