[JAVA] Nullpointer Exception generating Jaxrs

[maha79]

Description

When generating JaxRS code, I run in a Nullpointer exception.
This is caused by a string array within the body parameter in the json description.
The problem is in AbstractJavaCodegen Method

protected boolean needToImport(String type) {
    return super.needToImport(type) && type.indexOf(".") < 0;
}

There is a null value in the list of imports to check. This in turn results from this code in DefaultCodegen.java (Line 2581):

    // recursively add import
    CodegenProperty innerCp = cp;
    while(innerCp != null) {
       imports.add(innerCp.complexType);
       innerCp = innerCp.items;
    }

innerCp is not a complexType is this case what causes NULL to be added to the import.

Swagger-codegen version

2.2.3

Swagger declaration file content or url

"paths": {		
	    "/test": {
            "post": {
                "summary": "Test method to show error",
                "operationId": "test",
                "parameters": [
					{
						"name": "queryparam1",
						"in": "query",
						"type": "string"
					}, 
                    {
                        "name": "listOfStrings",
                        "in": "body",
                        "description": "An array of strings",
                        "required": true,
                        "schema": {
		                    "type": "array",
		                    "items": {
		                        "type": "string"
		                    }
                        }
                    }
                ]
            }
        }     

Command line used for generation

    <plugin>
        <groupId>io.swagger</groupId>
        <artifactId>swagger-codegen-maven-plugin</artifactId>
        <version>2.2.3</version>            
        <executions>                                    
  			<execution>
  				<id>generation-java</id>
  				<goals>
  					<goal>generate</goal>
  				</goals>
  				<configuration>
  					<inputSpec>test.json</inputSpec>
  					<language>jaxrs</language>  <!-- Defaults to jersey2 -->
  				</configuration>
  			</execution>
        </executions>
     </plugin>

Suggest a fix/enhancement

Add a null check to the needToImport method.

[wing328]

@maha79 thanks for reporting the issue. Do you mind submitting a PR with the suggested fix?

[set321go]

I'm seeing the same issue, I tracked down these PR's from the release notes that seem to concern the importMappings (which i think is causing the problem).
#5384
#6063

I tried adding importMappings but that didn't change anything.

task swaggerGen {
    doLast {
        def config = new CodegenConfigurator()
        config.lang = "java"
        config.inputSpec = "${project(':address-rest').swaggerSpecFile}"
        config.outputDir = "${buildDir}/swagger/client"
        config.groupId = "${project.group}"
        config.artifactId = "address-java-client"
        config.artifactVersion = "${project.version}"
        config.apiPackage = "${project.group}.client.${project.parent.name}.api"
        config.modelPackage = "${project.group}.client.${project.parent.name}.model"
        config.invokerPackage = "${project.group}.client.${project.parent.name}.invoker"
        config.library = "okhttp-gson"
        config.templateDir = "${projectDir}/src/main/swagger-templates/${config.library}"

        new DefaultGenerator()
                .opts(config.toClientOptInput())
                .generate()
    }
}

[set321go]

After further investigation the line in my code that results in a null getting into the imports set is public Response getAddresses(@ApiParam(value = "IDs to get by", required = true) List<String> addressIds)

As maha79 identified this occurs at L2582

                CodegenProperty innerCp = cp;
                while(innerCp != null) {
                    imports.add(innerCp.complexType);
                    innerCp = innerCp.items;
                }

The toString for this instance is inner(List<String>) and complexType is indeed null, should it be for this type?

Looking a little further, innerCp.items contains an entry whose toString is inner(String) which also has a complexType of null.

This is new code and was added as part of #5891 I reverted this and validated that my build passes afterwards.

[wing328]

@set321go do you mind submitting a PR with a proper null check when you've time? or share a spec so that we can more easily reproduce the issue while working on a fix later.

[akhalikov]

This should have been fixed in #6079.

[wing328]

@akhalikov thanks for confirming the issue has been addressed.