@Override
    public boolean equals(final Object o) {
        if (this == o) {
            return true;
        }
        if (o == null || getClass() != o.getClass()) {
            return false;
        }
        final SimpleMetaImpl meta = (SimpleMetaImpl) o;
        return id == meta.id;
    }
A lighter weight version of {@link Meta} with only key fields.
stroom-core-shared/src/main/java/stroom/meta/shared/SimpleMetaImpl.java