How to use

EitherTypeAdapter

in

org.eclipse.lsp4j.jsonrpc.json.adapters

@SuppressWarnings({ "rawtypes", "unchecked" })
@Override
public <T> TypeAdapter<T> create(Gson gson, TypeToken<T> typeToken) {
  if (!TypeUtils.isEither(typeToken.getType())) {
    return null;
  }
  return new EitherTypeAdapter(gson, typeToken);
}

@Override
public Either<L, R> read(JsonReader in) throws IOException {
  JsonToken next = in.peek();
  if (next == JsonToken.NULL) {
    in.nextNull();
    return null;
  }
  return create(next, in);
}

protected Either<L, R> create(JsonToken nextToken, JsonReader in) throws IOException {
  boolean matchesLeft = left.isAssignable(nextToken);
  boolean matchesRight = right.isAssignable(nextToken);
  if (matchesLeft && matchesRight) {
    if (leftChecker != null || rightChecker != null) {
      JsonElement element = new JsonParser().parse(in);
      if (leftChecker != null && leftChecker.test(element))
        // Parse the left alternative from the JSON element tree
        return createLeft(left.read(element));
      if (rightChecker != null && rightChecker.test(element))
        // Parse the right alternative from the JSON element tree
        return createRight(right.read(element));
    }
    throw new JsonParseException("Ambiguous Either type: token " + nextToken + " matches both alternatives.");
  } else if (matchesLeft) {
    // Parse the left alternative from the JSON stream
    return createLeft(left.read(in));
  } else if (matchesRight) {
    // Parse the right alternative from the JSON stream
    return createRight(right.read(in));
  } else {
    throw new JsonParseException("Unexpected token " + nextToken + ": expected " + left + " | " + right + " tokens.");
  }
}

@SuppressWarnings({ "rawtypes", "unchecked" })
@Override
public <T> TypeAdapter<T> create(Gson gson, TypeToken<T> typeToken) {
  if (!TypeUtils.isEither(typeToken.getType())) {
    return null;
  }
  return new EitherTypeAdapter(gson, typeToken);
}

protected Either<L, R> create(JsonToken nextToken, JsonReader in) throws IOException {
  boolean matchesLeft = left.isAssignable(nextToken);
  boolean matchesRight = right.isAssignable(nextToken);
  if (matchesLeft && matchesRight) {
    if (leftChecker != null || rightChecker != null) {
      JsonElement element = new JsonParser().parse(in);
      if (leftChecker != null && leftChecker.test(element))
        // Parse the left alternative from the JSON element tree
        return createLeft(left.read(element));
      if (rightChecker != null && rightChecker.test(element))
        // Parse the right alternative from the JSON element tree
        return createRight(right.read(element));
    }
    throw new JsonParseException("Ambiguous Either type: token " + nextToken + " matches both alternatives.");
  } else if (matchesLeft) {
    // Parse the left alternative from the JSON stream
    return createLeft(left.read(in));
  } else if (matchesRight) {
    // Parse the right alternative from the JSON stream
    return createRight(right.read(in));
  } else {
    throw new JsonParseException("Unexpected token " + nextToken + ": expected " + left + " | " + right + " tokens.");
  }
}

@Override
public Either<L, R> read(JsonReader in) throws IOException {
  JsonToken next = in.peek();
  if (next == JsonToken.NULL) {
    in.nextNull();
    return null;
  }
  return create(next, in);
}

  @SuppressWarnings("unchecked")
  @Override
  public <T> TypeAdapter<T> create(Gson gson, TypeToken<T> type) {
    Predicate<JsonElement> leftChecker = new PropertyChecker("start");
    Predicate<JsonElement> rightChecker = new PropertyChecker("range");
    TypeAdapter<Either<Range, PrepareRenameResult>> elementTypeAdapter = new EitherTypeAdapter<>(gson, ELEMENT_TYPE,
        leftChecker, rightChecker);
    return (TypeAdapter<T>) new CollectionTypeAdapter<>(gson, ELEMENT_TYPE.getType(), elementTypeAdapter,
        ArrayList::new);
  }
}

@SuppressWarnings("unchecked")
@Override
public <T> TypeAdapter<T> create(Gson gson, TypeToken<T> type) {
  PropertyChecker leftChecker = new PropertyChecker("location");
  PropertyChecker rightChecker = new PropertyChecker("range");
  TypeAdapter<Either<SymbolInformation, DocumentSymbol>> elementTypeAdapter = new EitherTypeAdapter<>(gson,
      ELEMENT_TYPE, leftChecker, rightChecker);
  return (TypeAdapter<T>) new CollectionTypeAdapter<>(gson, ELEMENT_TYPE.getType(), elementTypeAdapter, ArrayList::new);
}

  @SuppressWarnings("unchecked")
  @Override
  public <T> TypeAdapter<T> create(Gson gson, TypeToken<T> type) {
    Predicate<JsonElement> leftChecker = new PropertyChecker("start");
    Predicate<JsonElement> rightChecker = new PropertyChecker("range");
    TypeAdapter<Either<Range, PrepareRenameResult>> elementTypeAdapter = new EitherTypeAdapter<>(gson, ELEMENT_TYPE,
        leftChecker, rightChecker);
    return (TypeAdapter<T>) new CollectionTypeAdapter<>(gson, ELEMENT_TYPE.getType(), elementTypeAdapter,
        ArrayList::new);
  }
}

@SuppressWarnings("unchecked")
@Override
public <T> TypeAdapter<T> create(Gson gson, TypeToken<T> type) {
  PropertyChecker leftChecker = new PropertyChecker("location");
  PropertyChecker rightChecker = new PropertyChecker("range");
  TypeAdapter<Either<SymbolInformation, DocumentSymbol>> elementTypeAdapter = new EitherTypeAdapter<>(gson,
      ELEMENT_TYPE, leftChecker, rightChecker);
  return (TypeAdapter<T>) new CollectionTypeAdapter<>(gson, ELEMENT_TYPE.getType(), elementTypeAdapter, ArrayList::new);
}

@SuppressWarnings("unchecked")
@Override
public <T> TypeAdapter<T> create(Gson gson, TypeToken<T> type) {
  Predicate<JsonElement> leftChecker = new PropertyChecker("command", JsonPrimitive.class);
  Predicate<JsonElement> rightChecker = new PropertyChecker("edit").or(new PropertyChecker("command", JsonObject.class));
  TypeAdapter<Either<Command, CodeAction>> elementTypeAdapter = new EitherTypeAdapter<>(gson,
      ELEMENT_TYPE, leftChecker, rightChecker);
  return (TypeAdapter<T>) new CollectionTypeAdapter<>(gson, ELEMENT_TYPE.getType(), elementTypeAdapter, ArrayList::new);
}

  @SuppressWarnings("unchecked")
  @Override
  public <T> TypeAdapter<T> create(Gson gson, TypeToken<T> type) {
    Predicate<JsonElement> leftChecker = new PropertyChecker("textDocument").and(new PropertyChecker("edits"));
    Predicate<JsonElement> rightChecker = new PropertyChecker("kind");
    TypeAdapter<Either<TextDocumentEdit, ResourceOperation>> elementTypeAdapter = new EitherTypeAdapter<>(gson,
        ELEMENT_TYPE, leftChecker, rightChecker);
    return (TypeAdapter<T>) new CollectionTypeAdapter<>(gson, ELEMENT_TYPE.getType(), elementTypeAdapter, ArrayList::new);
  }
}

  @SuppressWarnings("unchecked")
  @Override
  public <T> TypeAdapter<T> create(Gson gson, TypeToken<T> type) {
    Predicate<JsonElement> leftChecker = new PropertyChecker("textDocument").and(new PropertyChecker("edits"));
    Predicate<JsonElement> rightChecker = new PropertyChecker("kind");
    TypeAdapter<Either<TextDocumentEdit, ResourceOperation>> elementTypeAdapter = new EitherTypeAdapter<>(gson,
        ELEMENT_TYPE, leftChecker, rightChecker);
    return (TypeAdapter<T>) new CollectionTypeAdapter<>(gson, ELEMENT_TYPE.getType(), elementTypeAdapter, ArrayList::new);
  }
}

@SuppressWarnings("unchecked")
@Override
public <T> TypeAdapter<T> create(Gson gson, TypeToken<T> type) {
  Predicate<JsonElement> leftChecker = new PropertyChecker("command", JsonPrimitive.class);
  Predicate<JsonElement> rightChecker = new PropertyChecker("edit").or(new PropertyChecker("command", JsonObject.class));
  TypeAdapter<Either<Command, CodeAction>> elementTypeAdapter = new EitherTypeAdapter<>(gson,
      ELEMENT_TYPE, leftChecker, rightChecker);
  return (TypeAdapter<T>) new CollectionTypeAdapter<>(gson, ELEMENT_TYPE.getType(), elementTypeAdapter, ArrayList::new);
}

@SuppressWarnings("unchecked")
@Override
public <T> TypeAdapter<T> create(Gson gson, TypeToken<T> type) {
  Predicate<JsonElement> leftChecker = new PropertyChecker("current").or(new PropertyChecker("newUri"));
  Predicate<JsonElement> rightChecker = new PropertyChecker("textDocument").and(new PropertyChecker("edits"));
  TypeAdapter<Either<ResourceChange, TextDocumentEdit>> elementTypeAdapter = new EitherTypeAdapter<>(gson,
      ELEMENT_TYPE, leftChecker, rightChecker);
  return (TypeAdapter<T>) new CollectionTypeAdapter<>(gson, ELEMENT_TYPE.getType(), elementTypeAdapter, ArrayList::new);
}

@SuppressWarnings("unchecked")
@Override
public <T> TypeAdapter<T> create(Gson gson, TypeToken<T> type) {
  Predicate<JsonElement> leftChecker = new PropertyChecker("current").or(new PropertyChecker("newUri"));
  Predicate<JsonElement> rightChecker = new PropertyChecker("textDocument").and(new PropertyChecker("edits"));
  TypeAdapter<Either<ResourceChange, TextDocumentEdit>> elementTypeAdapter = new EitherTypeAdapter<>(gson,
      ELEMENT_TYPE, leftChecker, rightChecker);
  return (TypeAdapter<T>) new CollectionTypeAdapter<>(gson, ELEMENT_TYPE.getType(), elementTypeAdapter, ArrayList::new);
}