BooleanAndOr.java Source code

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Here is the source code for BooleanAndOr.java

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/*
 * Test out combinations of Ands and Ors on Boolean values.
 * Some of these will probably throw a NullPointerException: which one(s)?
 * Pay attention to short-circuit evaluation; if the first subexpression
 * is known, do you need to evaluation the second??
 */
public class BooleanAndOr {
    public static void main(String[] a) {
        String s = null;

        // These use the conventional logical "and" (&&) and "or" (||).
        try {
            if ((s != null) && (s.length() > 0))
                System.out.println("At Point One");
            if ((s != null) || (s.length() > 0))
                System.out.println("At Point Two");
        } catch (Exception e) {
            System.out.print("Logical section threw ");
            e.printStackTrace();
        }

        // These use bitwise "and" (&) and "or" (|); is it valid? What results?
        try {
            if ((s == null) & (s.length() > 0))
                System.out.println("At Point Three");
            if ((s == null) | (s.length() > 0))
                System.out.println("At Point Four");
        } catch (Exception e) {
            System.out.print("Bitwise section threw ");
            e.printStackTrace();
        }
    }
}