Break & Continue statement in java

Break statement in java

break statement in Java programming language has the following two usages −

• When the break statement is encountered inside a loop, the loop is immediately terminated and the program control resumes at the next statement following the loop.
• It can be used to terminate a case in the switch statement (covered in the next chapter).

Syntax

The syntax of a break is a single statement inside any loop −

break;

Flow Diagram

Example

public class Test {

   public static void main(String args[]) {
      int [] numbers = {100, 200, 300, 400, 500};

      for(int x : numbers ) {
         if( x == 300 ) {
            break;
         }
         System.out.print( x );
         System.out.print("\n");
      }
   }
}

This will produce the following result −

Output

100
200

Continue statement in java

The continue keyword can be used in any of the loop control structures. It causes the loop to immediately jump to the next iteration of the loop.

• In a for loop, the continue keyword causes control to immediately jump to the update statement.
• In a while loop or do/while loop, control immediately jumps to the Boolean expression.

Syntax

The syntax of a continue is a single statement inside any loop −
continue;

Flow Diagram

Example

public class Test { public static void main(String args[]) { int [] numbers = {10, 20, 30, 40, 50}; for(int x : numbers ) { if( x == 30 ) { continue; } System.out.print( x ); System.out.print("\n"); } }}This will produce the following result −

Output

10 20 40 50

How to use do while loop in java

A do...while loop is similar to a while loop, except that a do...while loop is guaranteed to execute at least one time.

Syntax

Following is the syntax of a do...while loop −

do {
   // Statements
}while(Boolean_expression);

Notice that the Boolean expression appears at the end of the loop, so the statements in the loop execute once before the Boolean is tested.
If the Boolean expression is true, the control jumps back up to do statement, and the statements in the loop execute again. This process repeats until the Boolean expression is false.

Flow Diagram

Example

public class Test {

   public static void main(String args[]) {
      int x = 10;

      do {
         System.out.print("value of x : " + x );
         x++;
         System.out.print("\n");
      }while( x < 20 );
   }
}

This will produce the following result −

Output

value of x : 10
value of x : 11
value of x : 12
value of x : 13
value of x : 14
value of x : 15
value of x : 16
value of x : 17
value of x : 18
value of x : 19

How to use for loop in java

A for loop is a repetition control structure that allows you to efficiently write a loop that needs to be executed a specific number of times.
A for loop is useful when you know how many times a task is to be repeated.

Syntax

The syntax of a for loop is −

for(initialization; Boolean_expression; update) {
   // Statements
}

Here is the flow of control in a for loop −

• The initialization step is executed first, and only once. This step allows you to declare and initialize any loop control variables and this step ends with a semi colon (;).
• Next, the Boolean expression is evaluated. If it is true, the body of the loop is executed. If it is false, the body of the loop will not be executed and control jumps to the next statement past the for loop.
• After the body of the for loop gets executed, the control jumps back up to the update statement. This statement allows you to update any loop control variables. This statement can be left blank with a semicolon at the end.
• The Boolean expression is now evaluated again. If it is true, the loop executes and the process repeats (body of loop, then update step, then Boolean expression). After the Boolean expression is false, the for loop terminates.

Flow Diagram

Example

Following is an example code of the for loop in Java.

public class Test {

   public static void main(String args[]) {

      for(int x = 10; x < 20; x = x + 1) {
         System.out.print("value of x : " + x );
         System.out.print("\n");
      }
   }
}

This will produce the following result −

Output

value of x : 10
value of x : 11
value of x : 12
value of x : 13
value of x : 14
value of x : 15
value of x : 16
value of x : 17
value of x : 18
value of x : 19

How to use the while Loop in java

A while loop statement in Java programming language repeatedly executes a target statement as long as a given condition is true.

Syntax

The syntax of a while loop is −

while(Boolean_expression) {
   // Statements
}

Here, statement(s) may be a single statement or a block of statements. The condition may be any expression, and true is any non zero value.
When executing, if the boolean_expression result is true, then the actions inside the loop will be executed. This will continue as long as the expression result is true.
When the condition becomes false, program control passes to the line immediately following the loop.

Flow Diagram

Here, key point of the while loop is that the loop might not ever run. When the expression is tested and the result is false, the loop body will be skipped and the first statement after the while loop will be executed.

Example

public class Test {

   public static void main(String args[]) {
      int x = 10;

      while( x < 20 ) {
         System.out.print("value of x : " + x );
         x++;
         System.out.print("\n");
      }
   }
}

This will produce the following result −

Output

value of x : 10
value of x : 11
value of x : 12
value of x : 13
value of x : 14
value of x : 15
value of x : 16
value of x : 17
value of x : 18
value of x : 19

Java - Example for Assignment Operators

Copy and paste the following Java program in Test.java file. Compile and run this program −

Example

public class Test {

   public static void main(String args[]) {
      int a = 10;
      int b = 20;
      int c = 0;

      c = a + b;
      System.out.println("c = a + b = " + c );

      c += a ;
      System.out.println("c += a  = " + c );

      c -= a ;
      System.out.println("c -= a = " + c );

      c *= a ;
      System.out.println("c *= a = " + c );

      a = 10;
      c = 15;
      c /= a ;
      System.out.println("c /= a = " + c );

      a = 10;
      c = 15;
      c %= a ;
      System.out.println("c %= a  = " + c );

      c <<= 2 ;
      System.out.println("c <<= 2 = " + c );

      c >>= 2 ;
      System.out.println("c >>= 2 = " + c );

      c >>= 2 ;
      System.out.println("c >>= 2 = " + c );

      c &= a ;
      System.out.println("c &= a  = " + c );

      c ^= a ;
      System.out.println("c ^= a   = " + c );

      c |= a ;
      System.out.println("c |= a   = " + c );
   }
}

This will produce the following result −

Output

c = a + b = 30
c += a  = 40
c -= a = 30
c *= a = 300
c /= a = 1
c %= a  = 5
c <<= 2 = 20
c >>= 2 = 5
c >>= 2 = 1
c &= a  = 0
c ^= a   = 10
c |= a   = 10

Java - Example for Logical Operators

Copy and paste the following Java program in Test.java file and compile and run this program −

Example

public class Test {

   public static void main(String args[]) {
      boolean a = true;
      boolean b = false;

      System.out.println("a && b = " + (a&&b));
      System.out.println("a || b = " + (a||b) );
      System.out.println("!(a && b) = " + !(a && b));
   }
}

This will produce the following result −

Output

a && b = false
a || b = true
!(a && b) = true

Java - Example for Bitwise Operators

Copy and paste the following Java program in Test.java file and compile and run this program −

Example

public class Test {

   public static void main(String args[]) {
      int a = 60; /* 60 = 0011 1100 */
      int b = 13; /* 13 = 0000 1101 */
      int c = 0;

      c = a & b;        /* 12 = 0000 1100 */
      System.out.println("a & b = " + c );

      c = a | b;        /* 61 = 0011 1101 */
      System.out.println("a | b = " + c );

      c = a ^ b;        /* 49 = 0011 0001 */
      System.out.println("a ^ b = " + c );

      c = ~a;           /*-61 = 1100 0011 */
      System.out.println("~a = " + c );

      c = a << 2;       /* 240 = 1111 0000 */
      System.out.println("a << 2 = " + c );

      c = a >> 2;       /* 15 = 1111 */
      System.out.println("a >> 2  = " + c );

      c = a >>> 2;      /* 15 = 0000 1111 */
      System.out.println("a >>> 2 = " + c );
   }
}

This will produce the following result −

Output

a & b = 12
a | b = 61
a ^ b = 49
~a = -61
a << 2 = 240
a >> 15
a >>> 15