lib/core/entity/metadata/ColumnDecorators.js
function ManyToOne(elements) {
    return function (targetObject, propertyKey) {
        var entityMetadata = targetObject;
        if (!entityMetadata.manyToOneMap) {
            entityMetadata.manyToOneMap = {};
        }
        entityMetadata.manyToOneMap[propertyKey] = elements;
    };
}
function ManyToOne(elements) {
    return function (targetObject, propertyKey) {
        var entityMetadata = targetObject;
        if (!entityMetadata.manyToOneMap) {
            entityMetadata.manyToOneMap = {};
        }
        entityMetadata.manyToOneMap[propertyKey] = elements;
    };
}
Specifies a single-valued association to another entity class that has many-to-one multiplicity.

http://docs.oracle.com/javaee/7/api/javax/persistence/ManyToOne.html

@param elements
@returns {function(any, string)}
@constructor