[JAVA] enums with number type are not supported

Created by: le-jhe

Description

Given that a numerical enum is in my custom input types, openapi-generator "decides" to use BigDecimal for mapping the "type" : "number" (maybe because of something in my pom). The problem is that the java source code generated for the enum is not correct

  public enum LogLevelEnum {
    _0("0"),
    _1("1"),
    _2("2"),
    _3("3"),
    _4("4");
    private BigDecimal value;
    LogLevelEnum(BigDecimal value) {
      this.value = value;
    }

Correct code should be something like

  public enum LogLevelEnum {
    _0(BigDecimal.valueOf(0)),
    _1(BigDecimal.valueOf(1)),
    _2(BigDecimal.valueOf(2)),
    _3(BigDecimal.valueOf(3)),
    _4(BigDecimal.valueOf(4));

openapi-generator version

• 3.0.2
• 3.1.0-SNAPSHOT [master]

OpenAPI declaration file content or url

With the following type definition in my input .json file:

"logLevel" : {
            "type" : "number",
            "description" : "* some description",
            "enum" : [ 0, 1, 2, 3, 4 ]
          }

Command line used for generation

    <build>
        <plugins>
            <plugin>
                <groupId>org.openapitools</groupId>
                <artifactId>openapi-generator-maven-plugin</artifactId>
                <version>3.0.3</version>
                <dependencies>
                    <dependency>
                        <groupId>com.google.guava</groupId>
                        <artifactId>guava</artifactId>
                        <version>19.0</version>
                    </dependency>
                </dependencies>
                <configuration>
                    <language>java</language>
                    <inputSpec>${project.basedir}/../my-client/src/test/resources/my.json</inputSpec>
                    <addCompileSourceRoot>false</addCompileSourceRoot>
                    <apiPackage>${api-package}</apiPackage>
                    <modelPackage>${model-package}</modelPackage>
                    <configOptions>
                        <sourceFolder>${generated-sources-java-path}</sourceFolder>
                        <dateLibrary>java8</dateLibrary>
                    </configOptions>
                </configuration>
                <executions>
                    <execution>
                        <id>generate-jersey2</id>
                        <phase>generate-sources</phase>
                        <goals>
                            <goal>generate</goal>
                        </goals>
                        <configuration>
                            <library>jersey2</library>
                            <output>${generated-output-root-jersey2}</output>
                        </configuration>
                    </execution>

Steps to reproduce

mvn package

Suggest a fix/enhancement

Check AbstractJavaCodegen.java:1045 ( toEnumValue(...) )in the list of numerical types, BigDecimal is not there, thus the processor goes to default and just wraps escaped values with string