content: /*
   * 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.
   */
  package org.apache.beam.sdk.transforms.reflect;
  
  import java.lang.reflect.Method;
  import java.util.NoSuchElementException;
  import org.apache.beam.sdk.transforms.DoFn;
  import org.apache.beam.sdk.transforms.reflect.DoFnSignatures.FnAnalysisContext;
  import org.apache.beam.sdk.values.TypeDescriptor;
  
  /** Utilities for use in {@link DoFnSignatures} tests. */
  class DoFnSignaturesTestUtils {
    /** An empty base {@link DoFn} class. */
    static class FakeDoFn extends DoFn<Integer, String> {}
  
    /** An error reporter. */
    static DoFnSignatures.ErrorReporter errors() {
      return new DoFnSignatures.ErrorReporter(null, "[test]");
    }
  
    /**
     * A class for testing utilities that take {@link Method} objects. Use like this:
     *
     * <pre>{@code
     * Method m = new AnonymousMethod() {
     *   SomeReturnValue method(SomeParameters...) { ... }
     * }.getMethod();  // Will return the Method for "method".
     * }</pre>
     */
    static class AnonymousMethod {
      final Method getMethod() throws Exception {
        for (Method method : getClass().getDeclaredMethods()) {
          if ("method".equals(method.getName())) {
            return method;
          }
        }
        throw new NoSuchElementException("No method named 'method' defined on " + getClass());
      }
    }
  
    static DoFnSignature.ProcessElementMethod analyzeProcessElementMethod(AnonymousMethod method)
        throws Exception {
      return DoFnSignatures.analyzeProcessElementMethod(
          errors(),
          TypeDescriptor.of(FakeDoFn.class),
          method.getMethod(),
          TypeDescriptor.of(Integer.class),
          TypeDescriptor.of(String.class),
          FnAnalysisContext.create());
    }
  }
  