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A switch block comprises several case labels and an optional but highly recommended default label. By convention, statements that follow each case label end with a break statement, responsible for transferring the control to the end of the switch block. When omitted, the statements in the subsequent case label are executed. Because the break statement is optional, its omission omitting it produces no compiler warnings. If When this behavior is unintentional, it can cause unexpected control flow.

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In this noncompliant code example, the case wherein the card is 11, does not have lacks a break statement. As a result, execution continues with the statements for card = 12 are also executed.

int card = 11;

switch (card) {
  /* ... */
  case 11: 
    System.out.println("Jack");
  case 12: 
    System.out.println("Queen"); 
    break;
  case 13: 
    System.out.println("King"); 
    break;
  default: 
    System.out.println("Invalid Card"); 
    break;
}

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*MSC14-EX1*: The {{break}} statement at the end of the final case in a {{switch}} statement may be omitted; by convention, this is the {{default}} label. The {{break}} statement serves to transfer control to the end of the {{switch}} block; fall-through behavior also causes control to arrive at the end of the {{switch}} block. Consequently, control transfers to the statements following the {{switch}} block without regard to the presence or absence of the {{break}} statement. Conventionally, the last label is the {{default}} label. Nevertheless, the final case in a {{switch}} statement should end with a {{break}} statement, in accordance with good programming style (see \[[Rogue 2000|AA. Bibliography#Rogue 00]\]).

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Failure to include break statements may can cause unexpected control flow.

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