Difference between java 1.4 and java 1.5

Java programming language is simple,distributed , robust, object oriented & secure.The Java 2 SDK is developing environment that is used for building applications, applets, and components by using the Java programming language. The Java 2 SDK includes the following important tools that are useful for developing and testing programs written in the Java programming language and running on the Java platform.

java 1.4 :

java 1.4 contains the following features such as :
(1) The newly edition of Java, JDK 1.4 (or J2SE 1.4), includes new features like a new I/O system, newly framework, Java Web Start, and Java regular expressions. Java 2 Platform, Standard Edition (J2SE) is an advance version from J2SE 1.3. J2SE 1.4 adds the following new features and improve the functionality .

(2 ) Enhanced performance and scalability .

(3) And also improved reliability and serviceability.

(4 ) The Java 2 Runtime Environment (JRE) allows us to run applications written in Java programming language. Like the Java 2 SDK, it also contains the Java virtual machine(JVM) that converts the byte code into machine code , classes comprising the Java 2 Platform API which are required for running the java applications, and supporting files.

(5) Unlike the Java 2 SDK, it does not contain development tools such as compilers and debuggers.

java 1.5 :

Java 2 Platform standard Edition 5.0 is an advance version of JDK 1.4 (or J2SE 1.4) includes the more features .

(1) provides the enhancing for loop - Eliminates the error-proneness of iterators.

(2) generics - provides compile-time type safety for collections and avoids problems occur during type casting.

(3) autoboxing/unboxing - avoids manual conversion between primitive types (such as int) and wrapper types (such as Integer).

(4) metadata - provides a "declarative" programming style where the programmer says what should be done and tools emit the code to do it.

Java 2 Platform standard Edition 5.0 is the major revision to the java platform and language. It is currently slated to contain 15 component JSRs. Java J2SE also keeps the version number 1.5.0 or 1.5 in same places that are visible only to developers, or where the version number is parsed by programs. As mentioned 1.5.0 refers to exactly the same platform and products numbered 5.0 version 1.5.0 and 1.5 are used at

(i) java.version- gives the infomation about the system property
(ii) java -fullversion

(iii) javac -source 1.5

(iv) advance version jdk1.5.0 provides the installation directory

(vi) advance version of JDK1.4 provides jre1.5.0 installation directory