CriteriaServiceImpl.java 文件源码

@SuppressWarnings ({ "unchecked", "rawtypes" })
protected Predicate buildPredicate(Path<T> root, SearchField field)
{
    Path<T> tt = (!field.getField().contains(".")) ? root.get(field.getField()) : fetchNestedPath(root, field.getField());
    CriteriaBuilder criteriaBuilder = this.entitymanager.getCriteriaBuilder();

    Class<?> javaType = tt.getJavaType();

    if (!classCompatibleWithOperator(javaType, field.getOperator()))
    {
        throw new RuntimeException("operator incompatible with field");
    }

    Object valueObject = convertStringValueToObject(field.getValue(), javaType);
    switch (field.getOperator())
    {
        case GE:
            return criteriaBuilder.greaterThan((Expression) tt, (Comparable) valueObject);
        case GTE:
            return criteriaBuilder.greaterThanOrEqualTo((Expression) tt, (Comparable) valueObject);
        case LE:
            return criteriaBuilder.lessThan((Expression) tt, (Comparable) valueObject);
        case LTE:
            return criteriaBuilder.lessThanOrEqualTo((Expression) tt, (Comparable) valueObject);
        case NE: 
               return criteriaBuilder.notEqual(tt, valueObject); 
        case EX:
            return criteriaBuilder.like((Expression) tt, "%"+field.getValue()+"%");
        default:
        {
            //EQ
            return criteriaBuilder.equal(tt, valueObject);
        }
    }
}