Branching statements for the Java language Branch statement

1. What is the execution structure of a Java statement

Program flow control.

2. What are the structure of Java statements

There are three types of structures:

Sequential structure (execution code from top to bottom line of the program, no judgment and relay)

Select structure (conditional statement)　　　

Loop structure: Loop statement function (recurring execution of specific code if the recycle condition is met)

Circular statement Classification (for loop while loop Do/while loop)

For Loop statement format: for (initialization expression 1; Loop field expression 2; post-loop expression)

{

Loop statement body;

}

The specific code is as follows:

　　　　　　　　　　　　　　

public class Demo10
{
public static void Main (String[]args)
{
for (int i=0;i<5;i++)
{
System.out.println (i);
}
}

}

While loop statement format: while (conditional expression) {loop body statement}

The specific code is as follows:

public class Demo10

{

public static void Main (String[]args)

{

int i=0;

while (i)

{

System.out.println (i);

i++;

}

}

}

Do-while Loop statement Format do

{

loop body statement;

}

while (conditional expression statement);

The specific code is as follows:

public class Demo11

{

public static void Main (String[]args)

{

int i=0;

Do

{

System.out.println (i)

i++;

}

while (I>5);

}

}

　　　　　　　　　　　　　　　　　　　　　　　　

　　　　　　　　　　　　　　　　

　　　　　　　　　　　　　　　　

3. Mastering the Branch structure ()

4. Mastering the use of the IF statement

if (conditional statement) {... }

if (conditional statement) {... }else{... }

if (conditional statement) {... }else if (conditional statement) {... }

if (conditional statement) {... }else if (conditional statement) {... }else{... }

The specific code is as follows:

public class Demo1

{

public static void Main (String[]args)

{

int i=3;

if (i>4)

{

System.out.println (i);

}

}

}

5. Mastering the use of switch statements

Switch

Switch (1)

{

Case 0: statement block 1;break;

Case 1: statement block 2;

Case 2: statement block 3;

Case 3: statement block 4;break;

······

case N; statement block N; break;

Default: statement block N+1;break;

}

The specific code is as follows:

public class Demo9
{
public static void Main (String [] args)
{
int i=3; Used to denote the first quarter.
Switch (i)
{
Case 1:
System.out.println ("This is the first quarter");
Break
Case 2:
System.out.println ("This is the second quarter");
Break
Case 3:
System.out.println ("This is the third quarter");
Break
Case 4:
System.out.println ("This is the fourth quarter");
Break
Default
SYSTEM.OUT.PRINTLN ("incorrect output");

}
}

}

Conditional Statement-switch statement about rules

1 The return value of an expression must be one of the following types:

int byte char short

2 The value of the case sub-statement must be a constant, and the values in all case sub-statements should be different

3 The default statement is optional

4 The break statement is used to jump out of a switch statement block after executing a case branch

Branching statements for the Java language Branch statement