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 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
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package org.apache.jdo.tck.query.api;

import java.util.concurrent.BrokenBarrierException;
import java.util.concurrent.CyclicBarrier;
import javax.jdo.JDOFatalException;
import javax.jdo.JDOQueryInterruptedException;
import javax.jdo.JDOUnsupportedOptionException;
import javax.jdo.PersistenceManager;
import javax.jdo.Query;
import javax.jdo.Transaction;
import junit.framework.AssertionFailedError;
import org.apache.jdo.tck.pc.mylib.PCPoint;
import org.apache.jdo.tck.pc.mylib.PCPoint2;
import org.apache.jdo.tck.query.QueryTest;
import org.apache.jdo.tck.util.BatchTestRunner;
import org.apache.jdo.tck.util.ThreadExceptionHandler;

/**
 * <B>Title:</B> QueryCancel <br>
 * <B>Keywords:</B> query <br>
 * <B>Assertion ID:</B> A14.6.1-8 <br>
 * <B>Assertion Description: </B> These methods cancel a running query (or queries). The thread that
 * has its query canceled will throw a JDOQueryInterruptedException. If cancel is not supported
 * (most likely due to the underlying implementation not supporting cancel) then
 * JDOUnsupportedOptionException is thrown to the caller.
 *
 * <p>REMARK: This assertion seems to be untestable with the current TCK, thus I drop it from the
 * query.conf configuration.
 *
 * <p>Looks like Derby is evaluating the query on ResultSet.next() and thus the actual query
 * execution is too fast to be canceled.
 */
public class QueryCancel extends QueryTest {

  /** Time for the main thread to sleep after starting a parallel thread. */
  private static final int MAIN_SLEEP_MILLIS = 40;

  /** Number of instances to be created. */
  private static final int NO_OF_INSTANCES = 5000;

  /** */
  private static final String ASSERTION_FAILED = "Assertion A14.6.1-8 (QueryCancel) failed: ";

  /** Single String JDOQL Query to be canceled. */
  private static final String SSJDOQL =
      "select avg (this.x + point2.y) "
          + "from PCPoint "
          + "where this.y >= 0 && point2.x >= 0 "
          + "variables PCPoint2 point2 "
          + "import org.apache.jdo.tck.pc.mylib.PCPoint; "
          + "import org.apache.jdo.tck.pc.mylib.PCPoint2; ";

  /**
   * The <code>main</code> is called when the class is directly executed from the command line.
   *
   * @param args The arguments passed to the program.
   */
  public static void main(String[] args) {
    BatchTestRunner.run(QueryCancel.class);
  }

  /**
   * @throws Exception exception
   */
  @SuppressWarnings("unchecked")
  public void testCancel() throws InterruptedException {
    PersistenceManager pm = getPM();
    // Test query
    Query<PCPoint> query = pm.newQuery(SSJDOQL);
    query.compile();

    // Thread executing the query
    CyclicBarrier barrier = new CyclicBarrier(2);
    ThreadExceptionHandler group = new ThreadExceptionHandler();
    QueryExecutor runnable = new QueryExecutor(pm, query, barrier);
    Thread t = new Thread(group, runnable, "Query Executor");
    t.start();

    try {
      // Wait for the other thread
      barrier.await();

      // Wait a couple of millis such that the other thread can start query execution
      Thread.sleep(MAIN_SLEEP_MILLIS);

      // cancel query
      query.cancel(t);
      if (!isQueryCancelSupported()) {
        fail(
            ASSERTION_FAILED,
            "Query.cancel should throw a JDOQueryInterruptedException, "
                + "if query canceling is not supported ");
      }
    } catch (JDOUnsupportedOptionException | InterruptedException | BrokenBarrierException ex) {
      if (isQueryCancelSupported()) {
        fail(
            ASSERTION_FAILED,
            "Query.cancel should not result in a JDOQueryInterruptedException, "
                + "if query canceling is supported ");
      }
    }

    t.join();
    Throwable problem = group.getUncaughtException(t);
    if (problem != null) {
      if (problem instanceof AssertionFailedError) throw (AssertionFailedError) problem;
      else throw new JDOFatalException("Thread " + t.getName() + " results in exception ", problem);
    }
  }

  /**
   * @throws Exception exception
   */
  @SuppressWarnings("unchecked")
  public void testCancelAll() throws Exception {
    PersistenceManager pm = getPM();
    // Test query
    Query<PCPoint> query = pm.newQuery(SSJDOQL);
    query.compile();

    // Thread executing the query
    CyclicBarrier barrier = new CyclicBarrier(2);
    ThreadExceptionHandler group = new ThreadExceptionHandler();
    QueryExecutor runnable = new QueryExecutor(pm, query, barrier);
    Thread t = new Thread(group, runnable, "Query Executor");
    t.start();

    try {
      // cancel query
      // Wait for the other thread
      barrier.await();

      // Wait a couple of millis such that the other thread can start query execution
      Thread.sleep(MAIN_SLEEP_MILLIS);

      query.cancelAll();
      if (!isQueryCancelSupported()) {
        fail(
            ASSERTION_FAILED,
            "Query.cancel should throw a JDOQueryInterruptedException, "
                + "if query canceling is not supported ");
      }
    } catch (JDOUnsupportedOptionException ex) {
      if (isQueryCancelSupported()) {
        fail(
            ASSERTION_FAILED,
            "Query.cancel should not result in a JDOQueryInterruptedException, "
                + "if query canceling is supported ");
      }
    }

    t.join();
    Throwable problem = group.getUncaughtException(t);
    if (problem != null) {
      if (problem instanceof AssertionFailedError) throw (AssertionFailedError) problem;
      else throw new JDOFatalException("Thread " + t.getName() + " results in exception ", problem);
    }
  }

  /** Runnable class executing the query. */
  class QueryExecutor implements Runnable {

    final PersistenceManager pm;
    final CyclicBarrier barrier;
    final Query<?> query;

    QueryExecutor(PersistenceManager pm, Query<?> query, CyclicBarrier barrier) {
      this.pm = pm;
      this.query = query;
      this.barrier = barrier;
    }

    public void run() {
      Transaction tx = pm.currentTransaction();
      try {
        tx.begin();

        // wait for the other thread
        barrier.await();

        Object result = query.execute();
        tx.commit();
        tx = null;
        if (isQueryCancelSupported()) {
          fail(
              ASSERTION_FAILED,
              "Query.execute should result in a JDOQueryInterruptedException, "
                  + "if query canceling is supported.");
        }
      } catch (JDOQueryInterruptedException ex) {
        if (!isQueryCancelSupported()) {
          fail(
              ASSERTION_FAILED,
              "Query.execute should not result in a JDOQueryInterruptedException, "
                  + "if query canceling is not supported.");
        }
      } catch (Exception ex) {
        throw new RuntimeException(ex);
      } finally {
        if ((tx != null) && tx.isActive()) tx.rollback();
      }
    }
  }

  /**
   * @see org.apache.jdo.tck.JDO_Test#localSetUp()
   */
  @Override
  protected void localSetUp() {
    addTearDownClass(PCPoint.class);
    addTearDownClass(PCPoint2.class);

    // create PCPoint and PCPoint2 instances
    PersistenceManager pm = getPM();
    Transaction tx = pm.currentTransaction();
    try {
      tx.begin();
      for (int i = 0; i < NO_OF_INSTANCES; i++) {
        PCPoint obj = new PCPoint(i, i);
        pm.makePersistent(obj);
      }
      for (int i = 0; i < NO_OF_INSTANCES; i++) {
        PCPoint2 obj = new PCPoint2(i, i);
        pm.makePersistent(obj);
      }
      tx.commit();
      tx = null;
    } finally {
      if ((tx != null) && tx.isActive()) tx.rollback();
    }
  }
}