If...else if...else and switch statements, as well as the difference between the If...else If...else and JS

Java If...else if...else Statements

The If statement can be followed by a elseif...else statement, which detects a variety of possible scenarios.

When using the If,else if,else statement, the following points need to be noted:

• The IF statement has at most 1 else statements, and ELSE statements after all ElseIf statements.
• An If statement can have several ElseIf statements, which must precede the Else statement.
• Once one of the else if statements detects true, the other else if and else statements will skip execution. (This is different from JS, can be self-testing)

Java

The switch statement has the following rules:

• The variable type in the switch statement can be: Byte, short, int, or char. Starting with Java SE 7, switch supports string types, and case labels must be string constants or literals.

• A switch statement can have more than one case statement. Each case is followed by a value and a colon to compare.

• The data type of the value in the case statement must be the same as the data type of the variable, and can only be constants or literal constants.

• When the value of a variable is equal to the value of the case statement, the statement after the case statement starts executing until the break statement appears and jumps out of the switch statement.

• The switch statement terminates when a break statement is encountered. The program jumps to the statement following the switch statement execution. The case statement does not have to contain a break statement. If no break statement appears, the program continues to execute the next case statement until a break statement appears.

• A switch statement can contain a default branch, which must be the last branch of a switch statement. Default is executed when there is no case statement with the value equal to the value of the variable. The default branch does not require a break statement.

If...else if...else and switch statements, as well as the difference between the If...else If...else and JS