ActionScript 3 v/s Java 6 Summary
Here is a quick list of differences I found between AS3 and Java 6 (mostly language syntax and concepts)
- AS3 places classes inside package blocks. Which allows AS3 to have multiple package definitions per file
- In AS3 the variable have function scope not block scope
- AS3 is a mostly type safe language with Dynamic behavior. This means you can add new capabilities (functions and properties) to existing objects at run time.
- AS3 has metadata while Java has annotations
- In AS3 semicolons are options if you have one statement per line
- In AS3 casts look more like a function call through the type being cast or we can use the as operator
- AS3 does not support generics and typed collections, except it has typed arrays through the Vector class
- AS3 has E4X integrated into the language to query/manipulation XML
- In AS3, constructors are always public
- AS3 does not allow properties on interfaces. Only functions can be declared on interfaces
- There is no concept of “abstract” in AS3
- In AS3, because functions are Objects, they can be passed around (like Function Pointers)
- AS3 has the concept of anonymous functions useful for declaring callbacks or event handlers inline
- In AS3, the override keyword is required if the subclass declares a function with the same name
- AS3 does not support Function overloading. Default parameter values might help you achieve it to some extent
- AS3 has properties as a first-class citizen of the language. get and set keywords are defined as special getters/setters for properties
- AS3 allows Property access via strings
- AS3 supports Untyped property access – allows accessing property through the String accessor, even if the property is not present at compile time (you’ll get run-time error)
- All AS3 objects can act like String maps
- AS3 supports Untyped variables (mostly type safe language). This allows you to told references without declaring its type
- AS3 allows Initializing dynamic properties using JSON-like syntax. Create and Initializes the object in one statement
Thanks to Chet Haase for his insightful article on ActionScript for Java developers.
