src/main/java/com/googlecode/objectify/impl/QueryDef.java
public QueryDef andFilter(final Filter addFilter) {
		return filter(this.filter == null ? addFilter : CompositeFilter.and(this.filter, addFilter));
	}
public QueryDef andFilter(final Filter addFilter) {
		return filter(this.filter == null ? addFilter : CompositeFilter.and(this.filter, addFilter));
	}
Convenince method that creates a composite filter with any existing filter (if present)