content: /*
   * Copyright 1999-2018 Alibaba Group Holding Ltd.
   *
   * Licensed 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.
   */
  package com.alibaba.druid.pvt.pool;
  
  import com.alibaba.druid.mock.MockDriver;
  import com.alibaba.druid.pool.DruidDataSource;
  import com.alibaba.druid.stat.DruidDataSourceStatManager;
  import junit.framework.TestCase;
  import org.junit.Assert;
  
  import java.sql.Connection;
  import java.sql.PreparedStatement;
  import java.sql.ResultSet;
  import java.util.concurrent.CountDownLatch;
  import java.util.concurrent.CyclicBarrier;
  import java.util.concurrent.atomic.AtomicInteger;
  
  public class TestIdle3_Concurrent_Starvation extends TestCase {
      private MockDriver driver;
      private DruidDataSource dataSource;
  
      protected void setUp() throws Exception {
          DruidDataSourceStatManager.clear();
  
          driver = new MockDriver();
  
          dataSource = new DruidDataSource();
          dataSource.setUrl("jdbc:mock:xxx");
          dataSource.setDriver(driver);
          dataSource.setInitialSize(1);
          dataSource.setMaxActive(100);
          dataSource.setMaxIdle(100);
          dataSource.setMinIdle(1);
          dataSource.setMinEvictableIdleTimeMillis(300 * 1000); // 300 / 10
          dataSource.setTimeBetweenEvictionRunsMillis(180 * 1000); // 180 / 10
          dataSource.setTestWhileIdle(true);
          dataSource.setTestOnBorrow(false);
          dataSource.setValidationQuery("SELECT 1");
          dataSource.setFilters("stat");
      }
  
      protected void tearDown() throws Exception {
          dataSource.close();
          Assert.assertEquals(0, DruidDataSourceStatManager.getInstance().getDataSourceList().size());
      }
  
      public void test_idle2() throws Exception {
          // 第一次创建连接
          {
              Assert.assertEquals(0, dataSource.getCreateCount());
              Assert.assertEquals(0, dataSource.getActiveCount());
  
              Connection conn = dataSource.getConnection();
  
              Assert.assertEquals(dataSource.getInitialSize(), dataSource.getCreateCount());
              Assert.assertEquals(dataSource.getInitialSize(), driver.getConnections().size());
              Assert.assertEquals(1, dataSource.getActiveCount());
  
              conn.close();
              Assert.assertEquals(0, dataSource.getDestroyCount());
              Assert.assertEquals(1, driver.getConnections().size());
              Assert.assertEquals(1, dataSource.getCreateCount());
              Assert.assertEquals(0, dataSource.getActiveCount());
          }
  
          for (int i = 0; i < 1; ++i) {
              final int threadCount = 100;
              concurrent(threadCount);
          }
  
          // 连续打开关闭单个连接
          for (int i = 0; i < 100; ++i) {
              Assert.assertEquals(0, dataSource.getActiveCount());
              Connection conn = dataSource.getConnection();
  
              Assert.assertEquals(1, dataSource.getActiveCount());
              conn.close();
          }
          // Assert.assertEquals(2, dataSource.getPoolingCount());
      }
  
      private void concurrent(final int threadCount) throws Exception {
          Thread[] threads = new Thread[threadCount];
          final CountDownLatch startLatch = new CountDownLatch(1);
          final CountDownLatch endLatch = new CountDownLatch(threadCount);
  
          final AtomicInteger pass = new AtomicInteger();
  
          final CyclicBarrier closedBarrier = new CyclicBarrier(threadCount, new Runnable() {
              public void run() {
                  Assert.assertEquals(threadCount, dataSource.getPoolingCount());
                  dataSource.shrink(false);
                  Assert.assertEquals(0, dataSource.getActiveCount());
                  Assert.assertEquals(dataSource.getMinIdle(), dataSource.getPoolingCount());
                  if (pass.getAndIncrement() % 100 == 0) {
                      System.out.println("pass : " + pass.get());
                  }
              }
          });
          final CyclicBarrier closeBarrier = new CyclicBarrier(threadCount, new Runnable() {
              public void run() {
                  Assert.assertEquals(threadCount, dataSource.getActiveCount());
              }
          });
  
          for (int i = 0; i < threadCount; ++i) {
              threads[i] = new Thread("thread-" + i) {
                  public void run() {
                      try {
                          startLatch.await();
                          for (int i = 0; i < 1000 * 1; ++i) {
                              Connection conn = dataSource.getConnection();
                              closeBarrier.await();
                              PreparedStatement stmt = conn.prepareStatement("SELECT 1");
                              ResultSet rs = stmt.executeQuery();
                              rs.next();
                              rs.close();
                              stmt.close();
                              conn.close();
                              closedBarrier.await();
                          }
                      } catch (Exception e) {
                          e.printStackTrace();
                      } finally {
                          endLatch.countDown();
                      }
                  }
              };
          }
  
          startLatch.countDown();
          for (int i = 0; i < threadCount; ++i) {
              threads[i].start();
          }
  
          endLatch.await();
  
          // int max = count > dataSource.getMaxActive() ? dataSource.getMaxActive() : count;
          // Assert.assertEquals(max, driver.getConnections().size());
      }
  }
  