--- /dev/null
+<?php
+/*
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * This software consists of voluntary contributions made by many individuals
+ * and is licensed under the MIT license. For more information, see
+ * <http://www.doctrine-project.org>.
+ */
+
+namespace Doctrine\ORM\Query\Filter;
+
+use Doctrine\ORM\EntityManager,
+ Doctrine\ORM\Mapping\ClassMetaData,
+ Doctrine\ORM\Query\ParameterTypeInferer;
+
+/**
+ * The base class that user defined filters should extend.
+ *
+ * Handles the setting and escaping of parameters.
+ *
+ * @author Alexander <iam.asm89@gmail.com>
+ * @author Benjamin Eberlei <kontakt@beberlei.de>
+ * @abstract
+ */
+abstract class SQLFilter
+{
+ /**
+ * The entity manager.
+ * @var EntityManager
+ */
+ private $em;
+
+ /**
+ * Parameters for the filter.
+ * @var array
+ */
+ private $parameters;
+
+ /**
+ * Constructs the SQLFilter object.
+ *
+ * @param EntityManager $em The EM
+ */
+ final public function __construct(EntityManager $em)
+ {
+ $this->em = $em;
+ }
+
+ /**
+ * Sets a parameter that can be used by the filter.
+ *
+ * @param string $name Name of the parameter.
+ * @param string $value Value of the parameter.
+ * @param string $type The parameter type. If specified, the given value will be run through
+ * the type conversion of this type. This is usually not needed for
+ * strings and numeric types.
+ *
+ * @return SQLFilter The current SQL filter.
+ */
+ final public function setParameter($name, $value, $type = null)
+ {
+ if (null === $type) {
+ $type = ParameterTypeInferer::inferType($value);
+ }
+
+ $this->parameters[$name] = array('value' => $value, 'type' => $type);
+
+ // Keep the parameters sorted for the hash
+ ksort($this->parameters);
+
+ // The filter collection of the EM is now dirty
+ $this->em->getFilters()->setFiltersStateDirty();
+
+ return $this;
+ }
+
+ /**
+ * Gets a parameter to use in a query.
+ *
+ * The function is responsible for the right output escaping to use the
+ * value in a query.
+ *
+ * @param string $name Name of the parameter.
+ *
+ * @return string The SQL escaped parameter to use in a query.
+ */
+ final public function getParameter($name)
+ {
+ if (!isset($this->parameters[$name])) {
+ throw new \InvalidArgumentException("Parameter '" . $name . "' does not exist.");
+ }
+
+ return $this->em->getConnection()->quote($this->parameters[$name]['value'], $this->parameters[$name]['type']);
+ }
+
+ /**
+ * Returns as string representation of the SQLFilter parameters (the state).
+ *
+ * @return string String representation of the SQLFilter.
+ */
+ final public function __toString()
+ {
+ return serialize($this->parameters);
+ }
+
+ /**
+ * Gets the SQL query part to add to a query.
+ *
+ * @return string The constraint SQL if there is available, empty string otherwise
+ */
+ abstract public function addFilterConstraint(ClassMetadata $targetEntity, $targetTableAlias);
+}