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This compliant solution terminates each case (including the default case) with a break statement.:

int card = 11;

switch (card) {
  /* ... */
  case 11: 
    System.out.println("Jack");
    break;
  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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Exceptionally, when multiple cases require execution of identical code, then break statements may be omitted from all cases except the last one. Similarly, when processing for one case is a proper prefix of processing for one or more other cases, the break statement may be omitted from the prefix case. This should be clearly indicated with a comment. For example:

int card = 11;
int value;

// Cases 11,12,13 fall through to the same case 
switch (card) {
  // processingProcessing for this case requires a prefix
  // of the actions for the following three
  case 10:
    do_something(card);
    // intentionalIntentional fall-through
    // theseThese three cases are treated identically 
  case 11:        // breakBreak not required
  case 12:        // breakBreak not required
  case 13: 
    value = 10; 
    break;        // breakBreak required
  default: 
    // Handle Errorerror Conditioncondition 
}

Also, when a case ends with a return or throw statement, the break statement may be omitted.

Related Guidelines

Bibliography

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