Item Use exceptions only in exceptional circumstances

Avoid using exceptions for common flow control:

Exceptions should only be used for unexpected situations, not to control the flow of a program.

Problematic code example: trying to use an exception to end a loop when exceeding the limits of an array.

try {
    int i = 0;
    while (true) {
        System.out.println(array[i++]);
    }
} catch (ArrayIndexOutOfBoundsException e) {
    // Este código encerra o loop quando o índice ultrapassa o tamanho do array
}

Problems: This use of exceptions is inefficient and confusing. It is better to use a suitable loop structure.

for (int i = 0; i < array.length; i++) {
    System.out.println(array[i]);
}

API Design Implications:

A well-designed API should avoid forcing the use of exceptions into the normal flow.

Example: The Iterator interface provides the hasNext() method to check for more elements, avoiding unnecessary exceptions when calling next().

Iterator<String> iterator = list.iterator();
while (iterator.hasNext()) {
    System.out.println(iterator.next());
}

Alternatives to state-dependent methods:

Provide a separate method to test the state (hasNext) or a special return value, such as null or an Optional, when the expected state cannot be met.

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