Kotlin support for index access operators

[Bixilon]

In Kotlin you can define your own operators. You can use the ::set Method to add a object. See https://kotlinlang.org/docs/reference/keyword-reference.html for more.

I added the set method in JsonObject. It is a simple alias to add or addProperty.

Also I need the current String position in JsonReader. E.g I have a command as a string and the next argument is a JsonObject. I just want to know how many chars were read from the input string to determinate the next argument. Currently this looks like this:

    private static final Field JSON_READER_POS_FIELD;
    private static final Field JSON_READER_LINE_START_FIELD;

        new JsonReader(new StringReader(""));
        Class<?> jsonReadClass = JsonReader.class;
        try {
            JSON_READER_POS_FIELD = jsonReadClass.getDeclaredField("pos");
            JSON_READER_POS_FIELD.setAccessible(true);
            JSON_READER_LINE_START_FIELD = jsonReadClass.getDeclaredField("lineStart");
            JSON_READER_LINE_START_FIELD.setAccessible(true);
        } catch (NoSuchFieldException e) {
            e.printStackTrace();
            throw new RuntimeException(e);
        }

        try {
            return JSON_READER_POS_FIELD.getInt(jsonReader) - JSON_READER_LINE_START_FIELD.getInt(jsonReader) + 1;
        } catch (IllegalAccessException e) {
            throw new IllegalStateException();
        }

[Marcono1234]

Personally I am not sure whether adding more methods with different names but the same behavior as existing methods is really worth it, especially since the main target of this project seems to be Java. Have a look at https://github.com/square/moshi which is designed for Kotlin.

I have added some review comments, but it might not be worth it considering them because this project does not seem to be actively maintained anymore, see #1821.

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Note that I am not a maintainer of this project.

[Bixilon]

I don't know if it is still maintained, but still making this PR. Everything is resolved now.

[eamonnmcmanus]

Reviving this conversation. 🙂
This project is now maintained. However I agree with @Marcono1234 that syntactic convenience in Kotlin isn't a good enough reason to add a second name to existing methods. You can easily use Kotlin extension functions to achieve the same thing in your project:

operator fun JsonObject.set(property: String, value: JsonElement) = add(property, value)
operator fun JsonObject.set(property: String, value: String) = addProperty(property, value)
operator fun JsonObject.set(property: String, value: Number) = addProperty(property, value)
operator fun JsonObject.set(property: String, value: Boolean) = addProperty(property, value)
operator fun JsonObject.set(property: String, value: Char) = addProperty(property, value)

It would be good if there were a standard artifact to house extension functions like these. I don't think the main Gson artifact (com.google.code.gson:gson) would be the right place, though, because it would probably have to acquire a dependency on the Kotlin runtime.