TypedBuilder
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(New 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 clas...) |
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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:
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; } } }
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:
<T extends ElemBuilder & Href<T> & ClassName<T>>
as such the IDE provides reasonable code completion.