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2. Expression statement: An expression statement contains an expression. Variables, operators, literals and method
calls are all part of the Java expression and always evaluate a single value.
For example:
double radius = 2.2, area;
area = 3.142 * radius * radius;
Here, the first statement is a declarative statement and the second statement is an expression statement.
3. Control flow statement: Normally all statements execute in sequential order, but sometimes it becomes necessary
to execute a set of statements repeatedly for a number of times or as required by the condition of the program. This
is done by the control flow statements or control statements.
Control statements are used to decide in which direction the program will execute. There are mainly four types of
control statements. They are:
• Sequential statements
• Conditional statements
• Iterative statements
• Jump statements
7.1 SEQUENTIAL STATEMENTS
These statements normally execute sequentially from top to bottom in the order that the code appears. It follows the
Top – Down approach.
For example:
class cal
{
public static void main(int side)
{
int area;
area = side * side;
System.out.println("Area of a square : " +area);
}
}
7.2 CONDITIONAL STATEMENTS
According to the need of the program, the execution of the statements are directed on the basis of a condition. If the
condition is satisfied, then the statements given in the true part of the conditional statement is executed, otherwise
the statements in the else part will be executed. The conditional statements are of three types. They are:
• if statement
• ternary operator
• switch statement
7.2.1 ‘if’ statement
The ‘if’ statement consists of the statements given in its true as well as else parts and executes either set of statements
based on the result of a given condition. There are five types of if statements. They are:
• simple if statement
• if-else statement
• if and only if statement
• if else if statement
• nested if statement
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