Begin to read Java Language Specification(preface - chapter 1)

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Why Should every Javaer read Java Language Specification ?

Java Language Specification is wrote by some excellent programmers including James Gosling, who is the father of Java. The Spec describes some basic and import concepts in Java , like packages, classes and interfaces. When I wrote first Java code, some tutorials and books helped me. However, those tutorials and books are not the root of Java knowledge, this Java Language Specification is .

Some knowledges about Java won’t be mentioned in other books, but can be found in Java Language Specification, and you can believe in these descriptions . Sometimes, I found some mistakes in some Java books , it is very harmful for beginner to learn Java. Java Language Specification must be read so that you can correct some details you learned.

When a class is no longer needed, it may be unloaded.

I know class loading, but never know about class unloading. Chapter 12 tells me that. I guess , I will get more valuable points while traveling the specification.

Preface And Chapter 1 in Spec

The preface describes the most important three features in Java 8 :

  • lambda expressions
  • method references
  • functional interfaces

These features are given in Java 8, with compiler javac upgrading and Java standard libraries supporting.

And chapter 1 describes the organization of the specification which shows what each chapter talks about. At the same time, a 'hello world’ code snippet has been shown to us :

class Test {
    public static void main(String[] args) {
        for (int i = 0; i < args.length; i++)
            System.out.print(i == 0 ? args[i] : " " + args[i]);

That’s all.