NullnessReflectionExampleTest.java

import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import org.checkerframework.checker.nullness.qual.NonNull;
import org.checkerframework.common.reflection.qual.MethodVal;

/**
 * Example used in the reflection resolution section of the Checker Framework manual
 *
 * @author smillst
 */
public class NullnessReflectionExampleTest {
    @NonNull Location getCurrentLocation() {
        //...
        return new Location();
    }

    String getCurrentCity()
            throws NoSuchMethodException, SecurityException, IllegalAccessException,
                    IllegalArgumentException, InvocationTargetException {
        @MethodVal(
            className = "NullnessReflectionExampleTest",
            methodName = "getCurrentLocation",
            params = 0
        )
        Method toLowerCase = getClass().getMethod("getCurrentLocation");
        Location currentLocation = (Location) toLowerCase.invoke(this);
        return currentLocation.nameOfCity();
    }
}

class Location {
    String nameOfCity() {
        return "Seattle";
    }
}