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diff --git a/opendc-integration-jpa/src/main/kotlin/nl/atlarge/opendc/platform/JpaExperimentManager.kt b/opendc-integration-jpa/src/main/kotlin/nl/atlarge/opendc/platform/JpaExperimentManager.kt
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+++ b/opendc-integration-jpa/src/main/kotlin/nl/atlarge/opendc/platform/JpaExperimentManager.kt
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+/*
+ * MIT License
+ *
+ * Copyright (c) 2017 atlarge-research
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package nl.atlarge.opendc.platform
+
+import nl.atlarge.opendc.integration.jpa.schema.Experiment as InternalExperiment
+import nl.atlarge.opendc.integration.jpa.schema.ExperimentState
+import javax.persistence.EntityManager
+
+/**
+ * A manager for [Experiment]s received from a JPA database.
+ *
+ * @property manager The JPA entity manager to retrieve entities from the database from.
+ * @author Fabian Mastenbroek (f.s.mastenbroek@student.tudelft.nl)
+ */
+class JpaExperimentManager(private val manager: EntityManager) {
+	/**
+	 * The amount of experiments in the queue. This property makes a call to the database and does therefore not
+	 * run in O(1) time.
+	 */
+	val size: Int
+		get() {
+			return manager.createQuery("SELECT COUNT(e.id) FROM experiments e WHERE e.state = :s",
+					java.lang.Long::class.java)
+				.setParameter("s", ExperimentState.QUEUED)
+				.singleResult.toInt()
+		}
+
+	/**
+	 * Poll an [Experiment] from the database and claim it.
+	 *
+	 * @return The experiment that has been polled from the database or `null` if there are no experiments in the
+	 * 		   queue.
+	 */
+	fun poll(): Experiment<Unit>? {
+		manager.transaction.begin()
+		var experiment: InternalExperiment? = null
+		val results = manager.createQuery("SELECT e FROM experiments e WHERE e.state = :s",
+				InternalExperiment::class.java)
+			.setParameter("s", ExperimentState.QUEUED)
+			.setMaxResults(1)
+			.resultList
+
+
+		if (!results.isEmpty()) {
+			experiment = results.first()
+			experiment!!.state = ExperimentState.CLAIMED
+		}
+		manager.transaction.commit()
+		return experiment?.let { JpaExperiment(manager, it) }
+	}
+}