// Test case for Issue 337:
// https://github.com/typetools/checker-framework/issues/337

import javax.annotation.Nullable;

abstract class Issue337<R> {
    abstract R getThing(String key);

    @Nullable R m1(@Nullable String key) {
        return (key == null) ? null : getThing(key);
    }

    @Nullable R m1b(@Nullable String key) {
        return (key != null) ? getThing(key) : null;
    }

    @Nullable R m2(@Nullable String key) {
        return (key == null)
                ?
                // :: error: (argument.type.incompatible)
                getThing(key)
                : null;
    }

    @Nullable R m2b(@Nullable String key) {
        return (key != null)
                ? null
                :
                // :: error: (argument.type.incompatible)
                getThing(key);
    }
}