OpenApi boolean type variable java generated code is not correct.

Description

I am using openapi: 3.0.1 specification, defined an attribute with type: boolean but generated java code has boxed type of Boolean instead of boolean. Due to this, api parameter accepting null values.

I tried setting nullable:false, but no luck.

When I sent a request with hasBalance: null the same coming to server side without validating null checks.

Swagger-codegen version

// https://mvnrepository.com/artifact/io.swagger.codegen.v3/swagger-codegen-cli/3.0.36
swaggerCodegen 'io.swagger.codegen.v3:swagger-codegen-cli:3.0.36'

Swagger declaration file content or url

Command line used for generation

I used build.gradle file in springboot applicaiton.

buildscript {
	repositories {
	}

	dependencies {
	}
}

plugins {

        id 'java'
	id 'org.springframework.boot' version '3.0.1'
	id 'io.spring.dependency-management' version '1.1.0'	id 'org.hidetake.swagger.generator' version '2.19.2'

}

group = 'com.example'
version = '0.0.1-SNAPSHOT'
sourceCompatibility = '17'

repositories {
   mavenCentral()
}

dependencies {
	implementation 'org.springframework.boot:spring-boot-starter-web'
	implementation 'org.springframework.boot:spring-boot-starter-validation'
	
	testImplementation 'org.springframework.boot:spring-boot-starter-test'
	
	// For building the code generated by swagger codegen.
	// https://mvnrepository.com/artifact/io.swagger.core.v3/swagger-annotations/2.2.7
	implementation 'io.swagger.core.v3:swagger-annotations:2.2.8'

	// For generating code using swagger codegen.
	// https://mvnrepository.com/artifact/io.swagger.codegen.v3/swagger-codegen-cli/3.0.36
	swaggerCodegen 'io.swagger.codegen.v3:swagger-codegen-cli:3.0.36'


}

// https://openapi-generator.tech/docs/generators/java/
swaggerSources {
	dms {
		inputFile = file('specs/api/dms-openapi.yaml')
		code {
			language = 'spring'
			components = [models: true, apis: true]
			configFile = file('openapi-config.json')
			jvmArgs = ['--add-opens=java.base/java.util=ALL-UNNAMED']
		}
	}
}

Steps to reproduce

Related issues/PRs

Suggest a fix/enhancement

If type: boolean should not accept null values until unless we specify nullable: true.

That mean in the generated java code variable type should be

1. if type: boolean then it should be boolean aka primitive type.
2. if type: boolean and property of nullable: true then it should be boxed type Boolean

Reproduce the generated model from specs/api/dms-openapi.yaml using the build.gradle setup and openapi-config.json. Then trace boolean and nullable handling in the Java Spring generator templates and compare the generated output with the reported BalanceRequest example. Done means the generator has a verified behavior for non-nullable and nullable boolean properties, backed by a regression test.