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.csp.sentinel.slots;
  
  import com.alibaba.csp.sentinel.slotchain.AbstractLinkedProcessorSlot;
  import com.alibaba.csp.sentinel.slotchain.ProcessorSlotChain;
  import com.alibaba.csp.sentinel.slots.block.authority.AuthoritySlot;
  import com.alibaba.csp.sentinel.slots.block.degrade.DefaultCircuitBreakerSlot;
  import com.alibaba.csp.sentinel.slots.block.degrade.DegradeSlot;
  import com.alibaba.csp.sentinel.slots.block.flow.FlowSlot;
  import com.alibaba.csp.sentinel.slots.clusterbuilder.ClusterBuilderSlot;
  import com.alibaba.csp.sentinel.slots.logger.LogSlot;
  import com.alibaba.csp.sentinel.slots.nodeselector.NodeSelectorSlot;
  import com.alibaba.csp.sentinel.slots.statistic.StatisticSlot;
  import com.alibaba.csp.sentinel.slots.system.SystemSlot;
  import org.junit.Test;
  
  import static org.junit.Assert.*;
  
  /**
   * Test cases for {@link DefaultSlotChainBuilder}.
   *
   * @author cdfive
   */
  public class DefaultSlotChainBuilderTest {
  
      @Test
      public void testBuild() {
          DefaultSlotChainBuilder builder = new DefaultSlotChainBuilder();
          ProcessorSlotChain slotChain = builder.build();
          assertNotNull(slotChain);
  
          // Verify the order of slot
          AbstractLinkedProcessorSlot<?> next = slotChain.getNext();
          assertTrue(next instanceof NodeSelectorSlot);
  
          // Store the first NodeSelectorSlot instance
          NodeSelectorSlot nodeSelectorSlot = (NodeSelectorSlot) next;
  
          next = next.getNext();
          assertTrue(next instanceof ClusterBuilderSlot);
  
          next = next.getNext();
          assertTrue(next instanceof LogSlot);
  
          next = next.getNext();
          assertTrue(next instanceof StatisticSlot);
  
          next = next.getNext();
          assertTrue(next instanceof AuthoritySlot);
  
          next = next.getNext();
          assertTrue(next instanceof SystemSlot);
  
          next = next.getNext();
          assertTrue(next instanceof FlowSlot);
  
          next = next.getNext();
          assertTrue(next instanceof DefaultCircuitBreakerSlot);
  
          next = next.getNext();
          assertTrue(next instanceof DegradeSlot);
  
          next = next.getNext();
          assertNull(next);
  
          // Build again to verify different instances
          ProcessorSlotChain slotChain2 = builder.build();
          assertNotNull(slotChain2);
          // Verify the two ProcessorSlotChain instances are different
          assertNotSame(slotChain, slotChain2);
  
          next = slotChain2.getNext();
          assertTrue(next instanceof NodeSelectorSlot);
          // Store the second NodeSelectorSlot instance
          NodeSelectorSlot nodeSelectorSlot2 = (NodeSelectorSlot) next;
          // Verify the two NodeSelectorSlot instances are different
          assertNotSame(nodeSelectorSlot, nodeSelectorSlot2);
      }
  }
  