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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one
3    * or more contributor license agreements.  See the NOTICE file
4    * distributed with this work for additional information
5    * regarding copyright ownership.  The ASF licenses this file
6    * to you under the Apache License, Version 2.0 (the
7    * "License"); you may not use this file except in compliance
8    * with the License.  You may obtain a copy of the License at
9    *
10   *   http://www.apache.org/licenses/LICENSE-2.0
11   *
12   * Unless required by applicable law or agreed to in writing,
13   * software distributed under the License is distributed on an
14   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15   * KIND, either express or implied.  See the License for the
16   * specific language governing permissions and limitations
17   * under the License.
18   */
19  package org.apache.maven.index.cli;
20  
21  import java.lang.reflect.InvocationHandler;
22  import java.lang.reflect.InvocationTargetException;
23  import java.lang.reflect.Method;
24  
25  /**
26   * An {@link java.lang.reflect.InvocationHandler} that can be extended with methods from the proxied interface. While
27   * invocation it will look for a method within itself that matches the signature of the invoked proxy method. If found
28   * the method will be invoked and result returned, otherwise an {@link UnsupportedOperationException} will be thrown.
29   *
30   * @author Alin Dreghiciu
31   */
32  public class PartialImplementation implements InvocationHandler {
33  
34      public Object invoke(final Object proxy, final Method method, final Object[] args) throws Throwable {
35          try {
36              final Method localMethod = getClass().getMethod(method.getName(), method.getParameterTypes());
37              return localMethod.invoke(this, args);
38          } catch (NoSuchMethodException | IllegalAccessException e) {
39              throw new UnsupportedOperationException("Method " + method.getName() + "() is not supported");
40          } catch (InvocationTargetException e) {
41              throw e.getCause();
42          }
43      }
44  }