Java PuzzlersOddityMaking changeLong DivisionAdditionTweedledumTweedledee+=Last LaughIndecisionHelloGoodbyeThe reluctant constructorHello againThe EndJava PuzzlersFrom the book Java Puzzlersby Joshua Bloch and Neal GafterOddityThe following method tests whether its argument is odd:public static boolean isOdd(int i) { return i % 2 == 1;}Does it work?It gives the correct answer for ¾ of the integersMaking changepublic class Change { public static void main(String[] args) { System.out.println(2.00 - 1.10); }}0.8999999999999999Long Divisionpublic class LongDivision { public static void main(String[] args) { final long MICROS_PER_DAY = 24 * 60 * 60 * 1000 * 1000; final long MILLIS_PER_DAY = 24 * 60 * 60 * 1000; System.out.println(MICROS_PER_DAY / MILLIS_PER_DAY); }}5Additionpublic class Addition { public static void main(String[] args) { System.out.println(12345 + 5432l); }}17777TweedledumDeclare variables x and i such that x += i;is legal, but x = x + i;is not legalshort x = 0;int i = 123456;TweedledeeDeclare variables x and i such that x = x + i;is legal, but x += i;is not legalObject x = "Hello ";String i = "world!";+=public class PlusEquals { public static void main(String[] args) { int i = 2; i += 3.75; System.out.println(i); }}5Last Laughpublic class LastLaugh { public static void main(String[] args) { System.out.print("H" + "a"); System.out.print('H' + 'a'); }}Ha169Indecisionpublic class Indecisive { public static void main(String[] args) { System.out.println(decision()); } static boolean decision() { try { return true; } finally { return false; } }}falseHelloGoodbyepublic class HelloGoodbye { public static void main(String[] args) { try { System.out.println("Hello world!"); System.exit(0); } finally { System.out.println("Goodbye world!"); } }}Hello world!The reluctant constructorpublic class Reluctant { private Reluctant internalInstance = new Reluctant(); public Reluctant() throws Exception { throw new Exception("I'm not coming out!"); } public static void main(String[] args) { try { Reluctant b = new Reluctant(); System.out.println("Surprise!"); } catch (Exception e) { System.out.println("I told you so."); } }}Exception in thread "main" java.lang.StackOverflowErrorHello againpublic class Null { public static void main(String[] args) { ((Null)null).greet(); } public static void greet() { System.out.println("Hello world!"); }}Hello world!The
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