[BUG] [JAVA] Missing imports in okhttp-gson client

[swanysimon]

Bug Report Checklist

• Have you provided a full/minimal spec to reproduce the issue? https://github.com/swanysimon/java-generator-example-14599
• Have you validated the input using an OpenAPI validator (example)?
• Have you tested with the latest master to confirm the issue still exists?
• Have you searched for related issues/PRs?
• What's the actual output vs expected output?
• [Optional] Sponsorship to speed up the bug fix or feature request (example)

Description

I'm trying to upgrade my Gradle plugin version from 5.4.0 to 6.3.0 and running into an issue with generated enum classes for my API client.

There are a number of missing imports in https://github.com/juanavilactn/openapi-generator/blob/master/modules/openapi-generator/src/main/resources/Java/libraries/okhttp-gson/pojo.mustache. This is the list I get in my IDE that I have to manually add imports for with my enums:

com.google.gson.TypeAdapter
com.google.gson.stream.JsonReader
com.google.gson.stream.JsonWriter
java.io.IOException

openapi-generator version

6.3.0

OpenAPI declaration file content or url

Generation Details

import org.openapitools.generator.gradle.plugin.tasks.GenerateTask

plugins {
    id "java"
    id "org.openapi.generator" version "6.3.0"
}

group = "example.example"
version = "0.0.1"

repositories { mavenCentral() }

java { toolchain { languageVersion.set(JavaLanguageVersion.of(11)) } }

sourceSets { main { java.srcDirs += "${buildDir}/generated/src/main/java" } }

dependencies {
    implementation "com.google.code.gson:gson:2.8.9"
    implementation "com.squareup.okhttp3:logging-interceptor:4.9.3"
    implementation "com.squareup.okhttp3:okhttp:4.9.3"
    implementation "com.squareup.okio:okio:2.8.0"
    implementation "io.gsonfire:gson-fire:1.8.5"
    implementation "io.swagger:swagger-core:1.6.9"
    implementation "javax.annotation:javax.annotation-api:1.3.2"
    implementation "javax.ws.rs:javax.ws.rs-api:2.1.1"
    implementation "org.openapitools:jackson-databind-nullable:0.2.2"
}

def generateSchemaTask = tasks.register("generateJavaClient", GenerateTask) {
    generatorName = "java"
    group = project.group
    version = project.version
    inputSpec = file("openapi.yaml").toString()
    outputDir = "${buildDir}/generated"
    apiPackage = "example.example.api"
    modelPackage = "example.example.api.model"
    configOptions = [
            dateLibrary            : "java8",
            hideGenerationTimestamp: "true",
    ]
}

Steps to reproduce

Try to generate with the above with an enum object. I can work on a minimal example if it would actually be helpful, but it seems pretty straightforward.

Minimal example: https://github.com/swanysimon/java-generator-example-14599

Related issues/PRs

n/a

Suggest a fix

I can make this change myself since it is just adding imports, but this clearly made it through testing and its possible folks want a more thorough fix and/or testing.

[wing328]

I can work on a minimal example

please provide one for easier troubleshooting.

[swanysimon]

@wing328 Here's a (not) working example (heh): https://github.com/swanysimon/java-generator-example-14599

Updating the original comment too

[stowns]

I seem to have the same missing imports. Java11 with dateLibrary=java8 additionalParameter

[wing328]

@swanysimon if you change the spec to 3.0.2, it seems to work (there's another issue how the parameter in which int64 should be format instead)

[wing328]

@stowns please provide a spec to reproduce the issue.

[swanysimon]

Thanks for the update @wing328 . 3.0.2 does indeed seem to work, but then I run into issues with a nullable ref a la #5180. Will try to get that working after reading through that thread

[swanysimon]

Looks like I'm blocked on a problem extremely similar to #14041 or #12556 and cannot upgrade

[stowns]

ah yes @wing328 using swagger: "2.0"

[ole-v-v]

My 15 lines example here: https://github.com/ole-v-v/openapi-generator-java-bug-14599-example/blob/main/test.swagger.json
import java.io.IOException; is missing in the generated Test.java file.

[stowns]

Migrating my schema yaml from swagger 2.0 -> openapi 3.0.2 didn't solve the import issue. Still missing imports for IOException and TypeAdapter in my models using 6.3.0. Unfortunately, I can't share the schema :/ .

[ole-v-v]

Have you tested with the latest master to confirm the issue still exists? Yes, I have observed the bug on master (up to commit d7edbad from Wed Feb 15 02:12:39 2023 -0500 (inclusive)).

[vanwobe]

above PR should fix this issue of missing imports.

[wing328]

I've tested the fix (#15388) with the spec provided by @ole-v-v and confirmed the fix.

Thanks for the PR, which has just been merged. Please pull the latest master to give it a try.

[ole-v-v]

In a few tests using the latest from master (up to and including commit b6b8883 from Sun May 14 23:06:20 2023 +0800 inclusive) I was unable to reproduce the bug. Thanks for fixing.