Exceptions are handy Gotos and flags. Let's abuse them.

TL;DR: Do not use exceptions for flow control.

Problems

• Readability

• Principle of least astonishment Violation.

Solutions

1. Use Exceptions just for unexpected situations.

2. Exceptions handle contract violations. Read the contract.

Sample Code

Wrong

try {
    for (int i = 0;; i++)
        array[i]++;
    } catch (ArrayIndexOutOfBoundsException e) {}

//Endless loop without end condition

Right

for (int index = 0; index < array.length; index++)
        array[index]++;

//index < array.length breaks execution

Detection

This is a semantic smell. Unless we use machine learning linters it will be very difficult to find the mistakes.

Tags

• Readability

Conclusion

Exceptions are handy, and we should definitively use them instead of returning codes.

The boundary between correct usage and wrong usage is blur like so many design principles.

Relations

More info

• Don't use exceptions for flow control

• Java Zone

• Stack Exchange

• Stack Overflow

Credits

Photo by Greg Rosenke on Unsplash

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When debugging, novices insert corrective code; experts remove defective code.

Richard Pattis

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This article is part of the CodeSmell Series.