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This artifact provides a single jar that contains all classes required to use remote EJB and JMS, including all dependencies. It is intended for use by those not using maven, maven users should just import the EJB and JMS BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up with different versions on classes on the class path).

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/*
 * Copyright (C) 2012 The Guava Authors
 *
 * 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.google.common.reflect;

import static com.google.common.base.Preconditions.checkNotNull;
import static java.util.Objects.requireNonNull;

import com.google.common.collect.FluentIterable;
import com.google.common.collect.ImmutableList;
import java.lang.annotation.Annotation;
import java.lang.reflect.AnnotatedElement;
import java.lang.reflect.AnnotatedType;
import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Represents a method or constructor parameter.
 *
 * @author Ben Yu
 * @since 14.0
 */
@ElementTypesAreNonnullByDefault
public final class Parameter implements AnnotatedElement {

  private final Invokable declaration;
  private final int position;
  private final TypeToken type;
  private final ImmutableList annotations;

  /**
   * An {@link AnnotatedType} instance, or {@code null} under Android VMs (possible only when using
   * the Android flavor of Guava). The field is declared with a type of {@code Object} to avoid
   * compatibility problems on Android VMs. The corresponding accessor method, however, can have the
   * more specific return type as long as users are careful to guard calls to it with version checks
   * or reflection: Android VMs ignore the types of elements that aren't used.
   */
  private final @Nullable Object annotatedType;

  Parameter(
      Invokable declaration,
      int position,
      TypeToken type,
      Annotation[] annotations,
      @Nullable Object annotatedType) {
    this.declaration = declaration;
    this.position = position;
    this.type = type;
    this.annotations = ImmutableList.copyOf(annotations);
    this.annotatedType = annotatedType;
  }

  /** Returns the type of the parameter. */
  public TypeToken getType() {
    return type;
  }

  /** Returns the {@link Invokable} that declares this parameter. */
  public Invokable getDeclaringInvokable() {
    return declaration;
  }

  @Override
  public boolean isAnnotationPresent(Class annotationType) {
    return getAnnotation(annotationType) != null;
  }

  @Override
  @CheckForNull
  public  A getAnnotation(Class annotationType) {
    checkNotNull(annotationType);
    for (Annotation annotation : annotations) {
      if (annotationType.isInstance(annotation)) {
        return annotationType.cast(annotation);
      }
    }
    return null;
  }

  @Override
  public Annotation[] getAnnotations() {
    return getDeclaredAnnotations();
  }

  /** @since 18.0 */
  @Override
  public  A[] getAnnotationsByType(Class annotationType) {
    return getDeclaredAnnotationsByType(annotationType);
  }

  /** @since 18.0 */
  @Override
  public Annotation[] getDeclaredAnnotations() {
    return annotations.toArray(new Annotation[0]);
  }

  /** @since 18.0 */
  @Override
  @CheckForNull
  public  A getDeclaredAnnotation(Class annotationType) {
    checkNotNull(annotationType);
    return FluentIterable.from(annotations).filter(annotationType).first().orNull();
  }

  /** @since 18.0 */
  @Override
  public  A[] getDeclaredAnnotationsByType(Class annotationType) {
    @Nullable
    A[] result = FluentIterable.from(annotations).filter(annotationType).toArray(annotationType);
    @SuppressWarnings("nullness") // safe because the input list contains no nulls
    A[] cast = (A[]) result;
    return cast;
  }

  /**
   * Returns the {@link AnnotatedType} of the parameter.
   *
   * This method will fail if run under an Android VM.
   *
   * @since 25.1 for guava-jre (available since 32.0.0 in guava-android)
   */
  @SuppressWarnings({"Java7ApiChecker", "AndroidJdkLibsChecker"})
  @IgnoreJRERequirement
  public AnnotatedType getAnnotatedType() {
    return requireNonNull((AnnotatedType) annotatedType);
  }

  @Override
  public boolean equals(@CheckForNull Object obj) {
    if (obj instanceof Parameter) {
      Parameter that = (Parameter) obj;
      return position == that.position && declaration.equals(that.declaration);
    }
    return false;
  }

  @Override
  public int hashCode() {
    return position;
  }

  @Override
  public String toString() {
    return type + " arg" + position;
  }
}

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