support generate Scala code

[jxnu-liguobin]

Is your feature request related to a problem? Please describe.

Initially, it will be implemented by replacing parts of the syntax directly and using java collections as much as possible and java annotations (although annotations are not necessary for Scala). I will do it.

Of course, all the features on Java will be preserved. For example, builder class , javadoc and entity classes (it is not recommended to use var in functional lang , but in this pr varis default, and val is generated if immutableModels is true).

One of the problems that i can think of at present is that i can't build the basic types of Java in scala code, because Int in scala is equivalent to Java int(other primitive type), and Int itself is an object (optimized, so it still better than integer
), but i will use Integer directly at present.(can use putCustomTypeMappingIfAbsent to set scala type)

Describe the solution you'd like
A clear and concise description of what you want to happen.

Describe alternatives you've considered
A clear and concise description of any alternative solutions or features you've considered.

Additional context
Add any other context or screenshots about the feature request here.

If accept issue please assign to me, I have roughly worked out the template and the basic implementation, and will writegithub.graphqlsunit test.

This is example(maybe have some errors). There are a lot of annotations and var in this example, which is not a good style in Scala, but it can only be implemented this time:

1. input

package com.github.graphql

import java.util.StringJoiner

@javax.annotation.Generated(
    value = "com.kobylynskyi.graphql.codegen.GraphQLCodegen",
    date = "2020-12-31T23:59:59-0500"
)
case class AcceptTopicSuggestionInput(
    var clientMutationId: String,
    @javax.validation.constraints.NotNull
    var name: String,
    @javax.validation.constraints.NotNull
    var repositoryId: String
) {

    override def toString(): String = {
        val joiner = new StringJoiner(", ", "{ ", " }")
        if (clientMutationId != null) {
            joiner.add(s"clientMutationId: \"$clientMutationId\"")
        }
        if (name != null) {
            joiner.add(s"name: \"$name\"")
        }
        if (repositoryId != null) {
            joiner.add(s"repositoryId: \"$repositoryId\"")
        }
        joiner.toString()
    }
}

object AcceptTopicSuggestionInput {

    def builder(): AcceptTopicSuggestionInput.Builder = new Builder()

    class Builder {

        private var clientMutationId: String = _
        private var name: String = _
        private var repositoryId: String = _

        def setClientMutationId(clientMutationId: String): Builder = {
            this.clientMutationId = clientMutationId
            this
        }

        def setName(name: String): Builder = {
            this.name = name
            this
        }

        def setRepositoryId(repositoryId: String): Builder = {
            this.repositoryId = repositoryId
            this
        }

        def build(): AcceptTopicSuggestionInput = new AcceptTopicSuggestionInput(clientMutationId, name, repositoryId)

    }
}

2. resolver

package com.github.graphql


@javax.annotation.Generated(
    value = "com.kobylynskyi.graphql.codegen.GraphQLCodegen",
    date = "2020-12-31T23:59:59-0500"
)
trait AcceptTopicSuggestionMutationResolver {

    @throws[Exception]
    def acceptTopicSuggestion(input: AcceptTopicSuggestionInput): AcceptTopicSuggestionPayload

}

3. type

package com.github.graphql

import java.util.StringJoiner

@javax.annotation.Generated(
    value = "com.kobylynskyi.graphql.codegen.GraphQLCodegen",
    date = "2020-12-31T23:59:59-0500"
)
case class AcceptTopicSuggestionPayload(
    var clientMutationId: String,
    var topic: Topic
) {

    override def toString(): String = {
        val joiner = new StringJoiner(", ", "{ ", " }")
        if (clientMutationId != null) {
            joiner.add(s"clientMutationId: \"$clientMutationId\"")
        }
        if (topic != null) {
            joiner.add(s"topic: $topic")
        }
        joiner.toString()
    }
}

object AcceptTopicSuggestionPayload {

    def builder(): AcceptTopicSuggestionPayload.Builder = new Builder()

    class Builder {

        private var clientMutationId: String = _
        private var topic: Topic = _

        def setClientMutationId(clientMutationId: String): Builder = {
            this.clientMutationId = clientMutationId
            this
        }

        def setTopic(topic: Topic): Builder = {
            this.topic = topic
            this
        }

        def build(): AcceptTopicSuggestionPayload = new AcceptTopicSuggestionPayload(clientMutationId, topic)

    }
}

4. interface

package com.github.graphql


@javax.annotation.Generated(
    value = "com.kobylynskyi.graphql.codegen.GraphQLCodegen",
    date = "2020-12-31T23:59:59-0500"
)
trait Actor  {

    @javax.validation.constraints.NotNull
    def getAvatarUrl(): String

    @javax.validation.constraints.NotNull
    def getLogin(): String

    @javax.validation.constraints.NotNull
    def getResourcePath(): String

    @javax.validation.constraints.NotNull
    def getUrl(): String

}

5.type extend

package com.github.graphql

import java.util.StringJoiner

@javax.annotation.Generated(
    value = "com.kobylynskyi.graphql.codegen.GraphQLCodegen",
    date = "2020-12-31T23:59:59-0500"
)
case class BranchProtectionRule(
    @javax.validation.constraints.NotNull
    var branchProtectionRuleConflicts: BranchProtectionRuleConflictConnection,
    var creator: Actor,
    var databaseId: Integer,
    var dismissesStaleReviews: boolean,
    @javax.validation.constraints.NotNull
    var id: String,
    var isAdminEnforced: boolean,
    @javax.validation.constraints.NotNull
    var matchingRefs: RefConnection,
    @javax.validation.constraints.NotNull
    var pattern: String,
    @javax.validation.constraints.NotNull
    var pushAllowances: PushAllowanceConnection,
    var repository: Repository,
    var requiredApprovingReviewCount: Integer,
    var requiredStatusCheckContexts: java.util.List[String],
    var requiresApprovingReviews: boolean,
    var requiresCodeOwnerReviews: boolean,
    var requiresCommitSignatures: boolean,
    var requiresStatusChecks: boolean,
    var requiresStrictStatusChecks: boolean,
    var restrictsPushes: boolean,
    var restrictsReviewDismissals: boolean,
    @javax.validation.constraints.NotNull
    var reviewDismissalAllowances: ReviewDismissalAllowanceConnection
) extends Node {

    override def toString(): String = {
        val joiner = new StringJoiner(", ", "{ ", " }")
        if (branchProtectionRuleConflicts != null) {
            joiner.add(s"branchProtectionRuleConflicts: $branchProtectionRuleConflicts")
        }
        if (creator != null) {
            joiner.add(s"creator: $creator")
        }
        if (databaseId != null) {
            joiner.add(s"databaseId: $databaseId")
        }
        joiner.add(s"dismissesStaleReviews: $dismissesStaleReviews")
        if (id != null) {
            joiner.add(s"id: \"$id\"")
        }
        joiner.add(s"isAdminEnforced: $isAdminEnforced")
        if (matchingRefs != null) {
            joiner.add(s"matchingRefs: $matchingRefs")
        }
        if (pattern != null) {
            joiner.add(s"pattern: \"$pattern\"")
        }
        if (pushAllowances != null) {
            joiner.add(s"pushAllowances: $pushAllowances")
        }
        if (repository != null) {
            joiner.add(s"repository: $repository")
        }
        if (requiredApprovingReviewCount != null) {
            joiner.add(s"requiredApprovingReviewCount: $requiredApprovingReviewCount")
        }
        if (requiredStatusCheckContexts != null) {
            joiner.add(s"requiredStatusCheckContexts: $requiredStatusCheckContexts")
        }
        joiner.add(s"requiresApprovingReviews: $requiresApprovingReviews")
        joiner.add(s"requiresCodeOwnerReviews: $requiresCodeOwnerReviews")
        joiner.add(s"requiresCommitSignatures: $requiresCommitSignatures")
        joiner.add(s"requiresStatusChecks: $requiresStatusChecks")
        joiner.add(s"requiresStrictStatusChecks: $requiresStrictStatusChecks")
        joiner.add(s"restrictsPushes: $restrictsPushes")
        joiner.add(s"restrictsReviewDismissals: $restrictsReviewDismissals")
        if (reviewDismissalAllowances != null) {
            joiner.add(s"reviewDismissalAllowances: $reviewDismissalAllowances")
        }
        joiner.toString()
    }
}

object BranchProtectionRule {

    def builder(): BranchProtectionRule.Builder = new Builder()

    class Builder {

        private var branchProtectionRuleConflicts: BranchProtectionRuleConflictConnection = _
        private var creator: Actor = _
        private var databaseId: Integer = _
        private var dismissesStaleReviews: boolean = _
        private var id: String = _
        private var isAdminEnforced: boolean = _
        private var matchingRefs: RefConnection = _
        private var pattern: String = _
        private var pushAllowances: PushAllowanceConnection = _
        private var repository: Repository = _
        private var requiredApprovingReviewCount: Integer = _
        private var requiredStatusCheckContexts: java.util.List[String] = _
        private var requiresApprovingReviews: boolean = _
        private var requiresCodeOwnerReviews: boolean = _
        private var requiresCommitSignatures: boolean = _
        private var requiresStatusChecks: boolean = _
        private var requiresStrictStatusChecks: boolean = _
        private var restrictsPushes: boolean = _
        private var restrictsReviewDismissals: boolean = _
        private var reviewDismissalAllowances: ReviewDismissalAllowanceConnection = _

        def setBranchProtectionRuleConflicts(branchProtectionRuleConflicts: BranchProtectionRuleConflictConnection): Builder = {
            this.branchProtectionRuleConflicts = branchProtectionRuleConflicts
            this
        }

        def setCreator(creator: Actor): Builder = {
            this.creator = creator
            this
        }

        def setDatabaseId(databaseId: Integer): Builder = {
            this.databaseId = databaseId
            this
        }

        def setDismissesStaleReviews(dismissesStaleReviews: boolean): Builder = {
            this.dismissesStaleReviews = dismissesStaleReviews
            this
        }

        def setId(id: String): Builder = {
            this.id = id
            this
        }

        def setIsAdminEnforced(isAdminEnforced: boolean): Builder = {
            this.isAdminEnforced = isAdminEnforced
            this
        }

        def setMatchingRefs(matchingRefs: RefConnection): Builder = {
            this.matchingRefs = matchingRefs
            this
        }

        def setPattern(pattern: String): Builder = {
            this.pattern = pattern
            this
        }

        def setPushAllowances(pushAllowances: PushAllowanceConnection): Builder = {
            this.pushAllowances = pushAllowances
            this
        }

        def setRepository(repository: Repository): Builder = {
            this.repository = repository
            this
        }

        def setRequiredApprovingReviewCount(requiredApprovingReviewCount: Integer): Builder = {
            this.requiredApprovingReviewCount = requiredApprovingReviewCount
            this
        }

        def setRequiredStatusCheckContexts(requiredStatusCheckContexts: java.util.List[String]): Builder = {
            this.requiredStatusCheckContexts = requiredStatusCheckContexts
            this
        }

        def setRequiresApprovingReviews(requiresApprovingReviews: boolean): Builder = {
            this.requiresApprovingReviews = requiresApprovingReviews
            this
        }

        def setRequiresCodeOwnerReviews(requiresCodeOwnerReviews: boolean): Builder = {
            this.requiresCodeOwnerReviews = requiresCodeOwnerReviews
            this
        }

        def setRequiresCommitSignatures(requiresCommitSignatures: boolean): Builder = {
            this.requiresCommitSignatures = requiresCommitSignatures
            this
        }

        def setRequiresStatusChecks(requiresStatusChecks: boolean): Builder = {
            this.requiresStatusChecks = requiresStatusChecks
            this
        }

        def setRequiresStrictStatusChecks(requiresStrictStatusChecks: boolean): Builder = {
            this.requiresStrictStatusChecks = requiresStrictStatusChecks
            this
        }

        def setRestrictsPushes(restrictsPushes: boolean): Builder = {
            this.restrictsPushes = restrictsPushes
            this
        }

        def setRestrictsReviewDismissals(restrictsReviewDismissals: boolean): Builder = {
            this.restrictsReviewDismissals = restrictsReviewDismissals
            this
        }

        def setReviewDismissalAllowances(reviewDismissalAllowances: ReviewDismissalAllowanceConnection): Builder = {
            this.reviewDismissalAllowances = reviewDismissalAllowances
            this
        }

        def build(): BranchProtectionRule = new BranchProtectionRule(branchProtectionRuleConflicts, creator, databaseId, dismissesStaleReviews, id, isAdminEnforced, matchingRefs, pattern, pushAllowances, repository, requiredApprovingReviewCount, requiredStatusCheckContexts, requiresApprovingReviews, requiresCodeOwnerReviews, requiresCommitSignatures, requiresStatusChecks, requiresStrictStatusChecks, restrictsPushes, restrictsReviewDismissals, reviewDismissalAllowances)

    }
}

6. request

package com.github.graphql

import com.kobylynskyi.graphql.codegen.model.graphql.GraphQLOperation
import com.kobylynskyi.graphql.codegen.model.graphql.GraphQLOperationRequest
import java.util.{ LinkedHashMap => JLinkedHashMap }
import java.util.{ Map => JMap }
import java.util.Objects

@javax.annotation.Generated(
    value = "com.kobylynskyi.graphql.codegen.GraphQLCodegen",
    date = "2020-12-31T23:59:59-0500"
)
class AcceptTopicSuggestionMutationRequest extends GraphQLOperationRequest {

    private var alias: String = _
    private final lazy val input = new JLinkedHashMap[String, AnyRef]()

    def this(alias: String) {
        this()
        this.alias = alias
    }

    def setInput(input: AcceptTopicSuggestionInput ): Unit = {
        this.input.put("input", input)
    }

    override def getOperationType(): GraphQLOperation = AcceptTopicSuggestionMutationRequest.OPERATION_TYPE

    override def getOperationName(): String = AcceptTopicSuggestionMutationRequest.OPERATION_NAME

    override def getAlias(): String = if (alias != null) alias else AcceptTopicSuggestionMutationRequest.OPERATION_NAME

    override def getInput(): JMap[String, AnyRef] = input

    override def toString(): String = Objects.toString(input)
}

object AcceptTopicSuggestionMutationRequest {

    final val OPERATION_NAME: String = "acceptTopicSuggestion"
    final val OPERATION_TYPE: GraphQLOperation = GraphQLOperation.MUTATION

    def builder(): Builder = new Builder()

    class Builder {

        private var $alias: String = _
        private var input: AcceptTopicSuggestionInput = _

        def alias(alias: String): Builder = {
            this.$alias = alias
            this
        }

        def setInput(input: AcceptTopicSuggestionInput ): Builder = {
            this.input = input
            this
        }

        def build(): AcceptTopicSuggestionMutationRequest = {
            val obj = new AcceptTopicSuggestionMutationRequest($alias)
            obj.setInput(input)
            obj
        }

    }
}

7. response

package com.github.graphql

import com.kobylynskyi.graphql.codegen.model.graphql.GraphQLResult
import java.util.{ Map => JMap }

@javax.annotation.Generated(
    value = "com.kobylynskyi.graphql.codegen.GraphQLCodegen",
    date = "2020-12-31T23:59:59-0500"
)
class AcceptTopicSuggestionMutationResponse extends GraphQLResult[Map[String, AcceptTopicSuggestionPayload]] {

    def acceptTopicSuggestion(): AcceptTopicSuggestionPayload = {
        val data: JMap[String, AcceptTopicSuggestionPayload] = getData()
        if (data != null) data.get(AcceptTopicSuggestionMutationResponse.OPERATION_NAME) else null
    }

}

object AcceptTopicSuggestionMutationResponse {

    private final val OPERATION_NAME: String = "acceptTopicSuggestion"

}

8. projection

package com.github.graphql

import com.kobylynskyi.graphql.codegen.model.graphql.GraphQLResponseField
import com.kobylynskyi.graphql.codegen.model.graphql.GraphQLResponseProjection

/**
 * Response projection for AcceptTopicSuggestionPayload
 */
@javax.annotation.Generated(
    value = "com.kobylynskyi.graphql.codegen.GraphQLCodegen",
    date = "2020-12-31T23:59:59-0500"
)
class AcceptTopicSuggestionPayloadResponseProjection extends GraphQLResponseProjection {

    override def all$(): AcceptTopicSuggestionPayloadResponseProjection = all$(3)

    override def all$(int maxDepth): AcceptTopicSuggestionPayloadResponseProjection = {
        this.clientMutationId()
        if (projectionDepthOnFields.getOrDefault("AcceptTopicSuggestionPayloadResponseProjection.TopicResponseProjection.topic", 0) <= maxDepth) {
            projectionDepthOnFields.put("AcceptTopicSuggestionPayloadResponseProjection.TopicResponseProjection.topic", projectionDepthOnFields.getOrDefault("AcceptTopicSuggestionPayloadResponseProjection.TopicResponseProjection.topic", 0) + 1)
            this.topic(new TopicResponseProjection().all$(maxDepth - projectionDepthOnFields.getOrDefault("AcceptTopicSuggestionPayloadResponseProjection.TopicResponseProjection.topic", 0)))
        }
        this.typename()
        this
    }

    def clientMutationId(): AcceptTopicSuggestionPayloadResponseProjection  {
        clientMutationId(null)
    }

    def clientMutationId(alias: String): AcceptTopicSuggestionPayloadResponseProjection = {
        fields.add(new GraphQLResponseField("clientMutationId").alias(alias))
        this
    }

    def topic(subProjection: TopicResponseProjection ): AcceptTopicSuggestionPayloadResponseProjection  {
        topic(null, subProjection)
    }

    def topic(alias: String, subProjection: TopicResponseProjection): AcceptTopicSuggestionPayloadResponseProjection = {
        fields.add(new GraphQLResponseField("topic").alias(alias).projection(subProjection))
        this
    }

    def typename(): AcceptTopicSuggestionPayloadResponseProjection  {
        typename(null)
    }

    def typename(alias: String): AcceptTopicSuggestionPayloadResponseProjection = {
        fields.add(new GraphQLResponseField("__typename").alias(alias))
        this
    }


}

[kobylynskyi]

@jxnu-liguobin, I've reviewed your PR and it looks great to me.
Thank you for your contribution.
Will release the graphql-java-codegen-4.0.0 today.

[jxnu-liguobin]

thank you, i add a example with scala as new pr