What is the Difference between jdk1.4 and jdk1.5?

Answer 1

The new language features all have one thing in common: they take some common idiom and provide linguistic support for it.

In other words, they shift the responsibility for writing the boilerplate code from the programmer to the compiler. Because the source code is now free of this boilerplate, it's easier to write and read.

Because the compiler, unlike the programmer, never makes mistakes, the resulting code is also more likely to be free of bugs.

The following are the features added to jdk 1.5

# Generics - Provides compile-time type safety for collections and eliminates the drudgery of casting. Eg: you used to write (jdk 1.4)

List words = new ArrayList();

You'll have to say: (jdk 1.5)

List words = new ArrayList();

# Enhanced for loop - Eliminates the drudgery and error-proneness of iterators.

# Autoboxing/unboxing - Eliminates the drudgery of manual conversion between primitive types (such as int) and wrapper types (such as Integer).

# Typesafe enums - Provides all the well-known benefits of the Typesafe Enum pattern (Effective Java, Item 21) without the verbosity and the error-proneness.

# Static import - Lets you avoid qualifying static members with class names, without the shortcomings of the Constant Interface antipattern (Effective Java, Item 17).

# Metadata - Lets you avoid writing boilerplate code, by enabling tools to generate it from annotations in the source code. This leads to a "declarative" programming style where the programmer says what should be done and tools emit the code to do it.

Regards:

Kavitha N Yadav

(Java Developer)