Neonira
by Neonira

Categories

  • programming-language
  • EN

Tags

  • code
  • technology
  • Java

How easy is it to create Java messy code ?

It is often said that Java is simple. Simple to write, simple to create a new program. Let’s have a closer look to this statement and try to show that it only relies on conventions.

Foreseing a result in Java

The Java language has greatly simplified the coding. First, it is a strongly typed language. Second, some tricky classical features of languages have disapeared: no pointer as in C or C++, no precompilation phase, … We could continue to enumerate a long list of features, all contributing to Java simplicity. It seems at the first glance, that the assertion is true.

Of course, we could enter a great Java obfuscation contest, and come with a counter example that will prove that Java could be messy too! This is not what we would like to prove. We would like to show that using standard Java coding technics and practices, we could end up very easily to a difficult-to-predict result. Let’s try to create a such short program.

Our two classes example

Let’s consider the two following Java class definitions. The first class has two methods and a main. The second one holds two methods. All the class methods are composed by only one instruction. It cannot be simpler.

Could you figure out what will be the output of the program ?

first class

package uc2;

public class _1 {
	private final int _;
	public _1 (int __) { _ = __;}
	public String __ () { return "" + _; }
	
	public static void main(String[] _) {
            _l_._l(new _1(_.length == 0 ? 1 : _l_.l_(_[0])).__());
	}
}

second class

package uc2;

public class _l_ {
	public static void _l(String _) { System.out.println(_); }
	public static int  l_(String _) { return Integer.parseInt(_); }
}

Getting the result

For your information, the right result is displayed below.

All we wanted to show, is that from a really simple Java example,

Run without argument

1

####Run with the integer 1234 as argument

1234

Run with the string “java is not so simple” as argument

Exception in thread "main" java.lang.NumberFormatException: 
For input string: "java is not so simple"
  at java.lang.NumberFormatException.forInputString(...:48)
  at java.lang.Integer.parseInt(Integer.java:447)
  at java.lang.Integer.parseInt(Integer.java:497)
  at uc2._l_.l_(_l_.java:9)
  at uc2._1.main(_1.java:13)
java Result: 1

The result is the string representation of the first argument passed to the program, considered to be an integer. If no parameter is given, the result defaults to 1. If the first argument is not convertible to an integer, then a java.lang.NumberFormatException is thrown.

Did you discover the full solution ?

So, is Java messy ?

From a really simple Java example, it appears counter intuitive and difficult to guess the right result. Of course, an attentive and constant reading could help. This example shows that the mental effort to produce in order to understand the program behavior, and to guess the right result is much harder than foreseen.

It is a best practice to impose its own presentation and naming rules to avoid such situations. Nevertheless, going to far this way, could lead to an extraneous amount of work to conform to this naming rules.

Who knows about a rewritting application, that should help the reader to understand better the written version, without having to produce a great effort ? Imagine the strength of a such application, that will greatly simplify the maintenance, an therefore, cut down its costs.