public static <K, V, E extends SimpleExpression<? super V>> MapPath<K,V,E> mapPath(Class<? super K> keyType,
                                                                                       Class<? super V> valueType,
                                                                                       Class<E> queryType,
                                                                                       PathMetadata metadata) {
        return new MapPath<K,V,E>(keyType, valueType, queryType, metadata);
    }
Create a new Path expression

@param keyType key type
@param valueType value type
@param queryType value expression type
@param metadata path metadata
@param <K> key type
@param <V> value type
@param <E> value expression type
@return path expression
querydsl-core/src/main/java/com/querydsl/core/types/dsl/Expressions.java