Java: Converting from .NET Constructors

Question

We're converting some .NET 3.5 code to Java (Android).

This Java code gives the error:

Syntax error on token "Chapters", VariableDeclaratorId expected after this token

this.add (new Book() {Chapters=50, OneBasedBookID = 1, 
Long = "Bahai", Short = "ba", Color = c,   BookType = b; });

The types are all correct.

Answer 1

You are using .NET/C#'s ability to initialize properties at the time you create your object. To do it in Java (or in older C#), you are going to have to do it the long way.

Book book = new Book();
book.Chapters = 50;
// etc
this.add(book);

Answer 2

Java doesn't have object initializers, so this syntax is not valid.

Instead, you're probably looking to do something like this:

Book book = new Book();

book.Chapters = 50;
book.OneBasedBookID = 1;
book.Long = "Bahai";
book.Short = "ba";
book.Color = c;
book.BookType = b;

this.add(book);

Also note that Java has no concept of "proper" properties either, and typical "good" practice is to use getters/setters, and to not name your variables starting with upper-case letters. This wouldn't work for your Long and Short members though, and overall these practices may not provide any value in your scenario anyway.

Answer 3

You could use the anonymous class initializer trick:

this.add (new Book() {{
    Chapters=50;
    OneBasedBookID = 1;
    Long = "Bahai";
    Short = "ba";
    Color = c;
    BookType = b;
}});