How do I convert a Java Bean to a JsonObject?

The reason you are not able to see that constructor is since the JSONObject class that you are using is from the android-json package. You can see the same constructors in the Android JSONObject doc.

To get the JSONObject that you're expecting, you would need to add the dependency of org.json as below (either Maven or Gradle)

Maven dependency

<dependency>
    <groupId>org.json</groupId>
    <artifactId>json</artifactId>
    <version>20180813</version>
</dependency>

Gradle dependency

compile group: 'org.json', name: 'json', version: '20180813'

Then import this JSONObject class and you would see the constructor that you actually want.