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1   /*
2    * Copyright 2014 The Netty Project
3    *
4    * The Netty Project licenses this file to you under the Apache License,
5    * version 2.0 (the "License"); you may not use this file except in compliance
6    * with the License. You may obtain a copy of the License at:
7    *
8    *   http://www.apache.org/licenses/LICENSE-2.0
9    *
10   * Unless required by applicable law or agreed to in writing, software
11   * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
12   * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
13   * License for the specific language governing permissions and limitations
14   * under the License.
15   */
16  
17  package io.netty.channel;
18  
19  import io.netty.util.internal.ObjectUtil;
20  import io.netty.util.internal.StringUtil;
21  
22  import java.lang.reflect.Constructor;
23  
24  /**
25   * A {@link ChannelFactory} that instantiates a new {@link Channel} by invoking its default constructor reflectively.
26   */
27  public class ReflectiveChannelFactory<T extends Channel> implements ChannelFactory<T> {
28  
29      private final Constructor<? extends T> constructor;
30  
31      public ReflectiveChannelFactory(Class<? extends T> clazz) {
32          ObjectUtil.checkNotNull(clazz, "clazz");
33          try {
34              this.constructor = clazz.getConstructor();
35          } catch (NoSuchMethodException e) {
36              throw new IllegalArgumentException("Class " + StringUtil.simpleClassName(clazz) +
37                      " does not have a public non-arg constructor", e);
38          }
39      }
40  
41      @Override
42      public T newChannel() {
43          try {
44              return constructor.newInstance();
45          } catch (Throwable t) {
46              throw new ChannelException("Unable to create Channel from class " + constructor.getDeclaringClass(), t);
47          }
48      }
49  
50      @Override
51      public String toString() {
52          return StringUtil.simpleClassName(ReflectiveChannelFactory.class) +
53                  '(' + StringUtil.simpleClassName(constructor.getDeclaringClass()) + ".class)";
54      }
55  }