Systems Analysis and Design Assignment Example | Topics and Well Written Essays - 3000 words

Systems Analysis and Design - Assignment Example Unlike C++, which combines the syntax for structured, generic, and object-oriented programming, Java was built almost exclusively as an object-oriented language. All code is written inside a class, and everything is an object, with the exception of the intrinsic data types (ordinal and real numbers, boolean values, and characters), which are not classes for performance reasons. Java uses similar commenting methods to C++. There are three different styles of comment: a single line style marked with two slashes (//), a multiple line style opened with a slash asterisk ( ), and the Javadoc commenting style opened with a slash and two asterisks ( ). The Javadoc style of commenting allows the user to run the Javadoc executable to compile documentation for the program. Source files must be named after the public class they contain, appending the suffix .java, for example, HelloWorld.java. It must first be compiled into bytecode, using a Java compiler, producing a file named HelloWorld.class. Only then can it be executed, or launched. The java source file may only contain one public class but can contain multiple classes with less than public access and any number of public inner classes. A class that is not declared public may be stored in any .java file. The compiler will generate a class file for each class defined in the source file. The name of the class file is the name of the class, with .class appended. For class file generation, anonymous classes are treated as if their name were the concatenation of the name of their enclosing class, a $, and an integer. The keyword public denotes that a method can be called from code in other classes, or that a class may be used by classes outside the class hierarchy. The class hierarchy is related to the name of the directory in which the .java file is located. The keyword static in front of a method indicates a static method.