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swaggerswagger-codegen

How to fix java.lang.RuntimeException: missing swagger input or config?

I'm trying to generate java code from swagger.json using swagger-codegen-cli.jar but I get this exception:

Exception in thread "main" java.lang.RuntimeException: missing swagger input or config!
        at io.swagger.codegen.DefaultGenerator.generate(DefaultGenerator.java:763)
        at io.swagger.codegen.cmd.Generate.run(Generate.java:299)
        at io.swagger.codegen.SwaggerCodegen.main(SwaggerCodegen.java:35)

The command I'm trying to run is the following:

java -jar swagger-codegen-cli.jar generate -i swagger.json -l java -c java-config.json -o api-client
Solution

  • You are using Swagger Codegen 2.x which does not support OpenAPI 3.0.

    You need to use Swagger Codegen 3.x instead. You can download the latest 3.x CLI JAR from Maven Central:
    https://mvnrepository.com/artifact/io.swagger.codegen.v3/swagger-codegen-cli

    Here's a direct link to v. 3.0.20 CLI (the latest version as of the time of writing):
    https://repo1.maven.org/maven2/io/swagger/codegen/v3/swagger-codegen-cli/3.0.20/swagger-codegen-cli-3.0.20.jar


    Or if you prefer to build the codegen from the source code, version 3 is in the 3.0.0 branch:
    https://github.com/swagger-api/swagger-codegen/tree/3.0.0