View source

From APIDesign

You do not have permission to do that, for the following reason:

The action you have requested is limited to users in the group Bureaucrats.

You can view and copy the source of this page:

[[TBD]]

I need to write a builder for [[HTML]] DOM elements. Or rather React.js elements. How can we create a builder for all the difference elements without generating many [[Java]] classes? Here is an idea:

<source lang="java">

public abstract class ElemBuilder {
    ElemBuilder() {
    }
    
    public static <T extends ElemBuilder & Href<T> & ClassName<T>> T a() {
        return (T) new Impl("a");
    }
    
    public static <T extends ElemBuilder & ClassName<T>> T b() {
        return (T) new Impl("b");
    }
    
    public interface ClassName<T> {
        T className(String className);
    }
    
    public interface Href<T> {
        T href(String url);
    }
    
    private static final class Impl extends ElemBuilder 
    implements ClassName<ElemBuilder>, Href<ElemBuilder> {
        private final String name;

        private Impl(String name) {
            this.name = name;
        }
        
        @Override
        public ElemBuilder className(String className) {
            return this;
        }

        @Override
        public ElemBuilder href(String url) {
            return this;
        }
    }
}
</source>

The implementation of the builder '''Impl''' implements all the element interfaces, but each builder creating method - e.g. '''a''' or '''b''' - specify the attributes that are supported with the use of generics: 
<source lang="java">
<T extends ElemBuilder & Href<T> & ClassName<T>>
</source>
as such the IDE provides reasonable code completion.

[[Category:APIDesignPatterns]]
[[Category:APIDesignPatterns:Creational]]

Return to TypedBuilder.

Retrieved from "http://wiki.apidesign.org/wiki/TypedBuilder"

View source

From APIDesign

Views

Personal tools

blogs & look

Navigation

Search

Toolbox

View source

From APIDesign

Views

Personal tools

blogs & look

Navigation

Search

Toolbox

buy