Java Resolvers
Java Resolvers Plugin. Generate Java interfaces for your resolvers. Works with graphql-java library.
- Version
- 4.0.1
- Weekly downloads
- 928
- License
- MIT
- Updated
- Apr 19, 2026
Installation
npm i -D @graphql-codegen/java-resolvers
yarn add -D @graphql-codegen/java-resolvers
pnpm add -D @graphql-codegen/java-resolvers
bun add -D @graphql-codegen/java-resolvers
Config API Reference
package
type: string
Customize the Java package name. The default package name will be generated according to the output file path.
mappers
type: object
Allow you to replace specific GraphQL types with your custom model classes. This is useful when you want to make sure your resolvers returns the correct class.
The default value is the values set by defaultMapper configuration.
You can use a direct path to the package, or use package#class syntax to have it imported.
defaultMapper
type: string
Sets the default mapper value in case it’s not specified by mappers.
You can use a direct path to the package, or use package#class syntax to have it imported.
The default mapper is Java’s Object.
Default value: “Object”
className
type: string
Allow you to customize the parent class name. Default value: “Resolvers”
listType
type: string
Allow you to customize the list type. Default value: “Iterable”
strictScalars
type: boolean
Makes scalars strict.
If scalars are found in the schema that are not defined in scalars
an error will be thrown during codegen.
Default value: “false”
defaultScalarType
type: string
Allows you to override the type that unknown scalars will have. Default value: “unknown”
scalars
type: object
Extends or overrides the built-in scalars and custom GraphQL scalars to a custom type.
namingConvention
type: object
Allow you to override the naming convention of the output.
You can either override all namings, or specify an object with specific custom naming convention per output.
The format of the converter must be a valid module#method.
Allowed values for specific output are: typeNames, enumValues.
You can also use “keep” to keep all GraphQL names as-is.
Additionally, you can set transformUnderscore to true if you want to override the default behavior,
which is to preserve underscores.
Available case functions in change-case-all are camelCase, capitalCase, constantCase, dotCase, headerCase, noCase, paramCase, pascalCase, pathCase, sentenceCase, snakeCase, lowerCase, localeLowerCase, lowerCaseFirst, spongeCase, titleCase, upperCase, localeUpperCase and upperCaseFirst
See more
Default value: “change-case-all#pascalCase”
typesPrefix
type: string
Prefixes all the generated types. Default value: ""
typesSuffix
type: string
Suffixes all the generated types. Default value: ""
enumPrefix
type: boolean
Allow you to disable prefixing for generated enums, works in combination with typesPrefix.
Default value: “true”
enumSuffix
type: boolean
Allow you to disable suffixing for generated enums, works in combination with typesSuffix.
Default value: “true”
useTypeImports
type: boolean
Will use import type {} rather than import {} when importing only types. This gives
compatibility with TypeScript’s “importsNotUsedAsValues”: “error” option
Default value: “false”
inlineFragmentTypes
type: string
Whether fragment types should be inlined into other operations. “inline” is the default behavior and will perform deep inlining fragment types within operation type definitions. “combine” is the previous behavior that uses fragment type references without inlining the types (and might cause issues with deeply nested fragment that uses list types). “mask” transforms the types for use with fragment masking. Useful when masked types are needed when not using the “client” preset e.g. such as combining it with Apollo Client’s data masking feature. Default value: “inline”
emitLegacyCommonJSImports
type: boolean
Emit legacy common js imports.
Default it will be true this way it ensure that generated code works with non-compliant bundlers.
Default value: “true”
importExtension
type: object
Append this extension to all imports. Useful for ESM environments that require file extensions in import statements.
printFieldsOnNewLines
type: boolean
If you prefer to have each field in generated types printed on a new line, set this to true. This can be useful for improving readability of the resulting types, without resorting to running tools like Prettier on the output. Default value: “false”
includeExternalFragments
type: boolean
Whether to include external fragments in the generated code. External fragments are not defined in the same location as the operation definition. Default value: “false”
The java-resolvers plugin creates Java interfaces for the resolvers’ signature.
It works with graphql-java library, and it uses it’s DataFetcher API.
You can use this plugin to generate interfaces and later implement them, this way you can always tell if one of the fields is missing a resolvers:
Prepare your environment
To use the GraphQL Code Generator with Java, start by adding the
com.moowork.node Gradle plugin to your
build.gradle:
plugins {
id "com.moowork.node" version "1.3.1"
}
Then, add the following in order to make sure you are running the code-generator on each build:
build.dependsOn yarn
Then, create a package.json file in your project root, with the following content:
{
"name": "java-app",
"scripts": {
"postinstall": "graphql-codegen"
},
"dependencies": {
"graphql": "14.5.8",
"@graphql-codegen/cli": "1.7.0",
"@graphql-codegen/RELEVANT_PLUGIN": "1.7.0"
}
}
Then, create codegen.yml file in your root directory, pointing to your schema, and add the plugins
you need. For example:
schema: src/main/resources/schema.graphqls
generates:
src/main/java/com/my-name/my-app/generated/File.java:
- RELEVANT_PLUGIN # Replace with your plugin name
Also, make sure you add the following to your .gitignore file:
yarn.lock
node_modules
Now, run gradle yarn to install the dependencies for the first time.
Next time, the codegen will run automatically each time you run your Gradle build script.