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General Best Practices

General Best Practices

This lesson discusses best practices for various aspects of Java Programming

We'll cover the following...

General Best Practices

  1. Strive to minimize the scope of a local variable The best way for minimizing the scope of a local variable is to declare it where it is first used.

    Bad Practice

            // Variable not used immediately but declared
        Random random = new Random(System.currentTimeMillis());

        for (int i = 0; i < 10; i++) {
            // ... for body
        }

        for (int i = 0; i < 10; i++) {
            // ... for body
        }

        // ... more processing
        // .
        // .
        // .
        // ...

        if (random.nextBoolean()) {
            // ... if body
        }

    Better Practice

            for (int i = 0; i < 10; i++) {
            // ... for body
        }

        for (int i = 0; i < 10; i++) {
            // ... for body
        }

        // ... more processing
        // .
        // .
        // .
        // ...
       
        // Variable declared closer to where it gets used
        Random random = new Random(System.currentTimeMillis());
        if (random.nextBoolean()) {
            // ... if body
        }

  2. Initialize every local variable when it is being declared. If you don’t yet have enough information to initialize a variable sensibly, postpone declaring it. One exception to this rule can be a ...