That's a nice approach.
On Tuesday, March 22, 2016 at 3:25:13 AM UTC-4, Ignacio Baca Moreno-Torres
wrote:
>
> If your concert is to be able to write one-line initializers, and you are
> using java8 syntax you also do something like that:
>
> public static <T> T apply(T t, Consumer<T> fn) {
> fn.accept(t);
> return t;
> }
>
> @JsType(isNative = true, namespace = JsPackage.GLOBAL, name = "Object")
> class SomeObjectLiteral {
> int field1;
> String field2;
> }
>
> {
> SomeObjectLiteral sol = apply(new SomeObjectLiteral(), o -> { o.field1 =
> 1; o.field2 = "str"; });
>
> }
>
>
> Copied from kotlin (although without method extensions and method inline
> is not the same ;)), this is usable for client and server code when you
> need to initialize small pojos without fluent api.
>
> On Tuesday, March 22, 2016 at 5:42:23 AM UTC+1, Paul Stockley wrote:
>>
>> I have come up with 3 approaches to creating object literals given the
>> current JsInterop capabilities:
>>
>> *1) Construct and set the fields individually*
>>
>> @JsType(isNative = true, namespace = JsPackage.GLOBAL, name = "Object")
>> class SomeObjectLiteral {
>>
>> int field1;
>>
>> String field2;
>>
>> }
>>
>>
>> SomeObjectLiteral o = new SomeObjectLiteral();
>>
>> o.field1 = 1;
>>
>> o.field2 = "Some value";
>>
>>
>> *2) Define a fluent interface*
>>
>>
>> @JsType(isNative = true, namespace = JsPackage.GLOBAL, name = "Object")
>> class SomeObjectLiteral {
>>
>> int field1;
>>
>> String field2;
>>
>>
>>
>> @JsOverlay
>> public final SomeObjectLiteral Field1(int v) {
>> field1 = v;
>> return this;
>> }
>>
>>
>> @JsOverlay
>> public final SomeObjectLiteral Field2(String v) {
>> field2 = v;
>> return this;
>> }
>>
>> }
>>
>>
>> You can then write
>>
>>
>> new SomeObjectLiteral().Field1(1).Field2("A value");
>>
>>
>> Note I didn't call the setter setFieldx. This is because you currently get a
>> runtime error if you do this.
>>
>>
>>
>> *2) Use an ObjectLiteral Helper*
>>
>>
>> You can define a helper similar to
>>
>>
>> public class ObjectLiteral {
>> public static <O> O $(O base, Object ...fieldValues) {
>> String fieldName = null;
>>
>> for(Object f : fieldValues) {
>> if (fieldName == null)
>> fieldName = (String)f;
>> else {
>> if (f instanceof Integer)
>> setField(base, fieldName, ((Integer) f).intValue());
>> else if (f instanceof Double)
>> setField(base, fieldName, ((Double) f).doubleValue());
>> else if (f instanceof Boolean)
>> setField(base, fieldName, ((Boolean) f).booleanValue());
>> else
>> setField(base, fieldName, f);
>>
>> fieldName = null;
>> }
>> }
>>
>> return base;
>> }
>>
>> private final static native void setField(Object literal, String
>> fieldName, int i) /*-{
>> literal[fieldName] = i;
>> }-*/;
>>
>> private final static native void setField(Object literal, String
>> fieldName, double d) /*-{
>> literal[fieldName] = d;
>> }-*/;
>>
>> private final static native void setField(Object literal, String
>> fieldName, boolean b) /*-{
>> literal[fieldName] = b;
>> }-*/;
>>
>> private final static native void setField(Object literal, String
>> fieldName, Object o) /*-{
>> literal[fieldName] = o;
>> }-*/;
>> }
>>
>>
>> You can then write
>>
>>
>> import static com.xxx.ObjectLiteral.$;
>>
>>
>> @JsType(isNative = true, namespace = JsPackage.GLOBAL, name = "Object")
>> class SomeObjectLiteral {
>>
>> int field1;
>>
>> String field2;
>>
>> }
>>
>>
>> $(new SomeObjectLiteral(), "field1",123, "field2","some value")
>>
>>
>> You would probably want to add some more error checking to the helper. This
>> approach probably isn't
>>
>> particularly efficient, especially if you pass a lot of field values that
>> get boxed into Object primitives.
>>
>> It would be nice if the compiler unboxed varargs passed to isNative=true
>> methods. If this was true you
>>
>> could write a much more efficient javascript version.
>>
>>
>>
>>
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