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Snowflake Common Package

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/*
 * Copyright (c) 2012, 2013 Snowflake Computing Inc. All right reserved.
 */
package net.snowflake.common.util;

import java.lang.annotation.Annotation;
import java.lang.reflect.Field;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.LinkedList;
import java.util.List;

/**
 * Class utilities
 *
 * @author jhuang
 */
public class ClassUtil {

  /**
   * Retrieving fields list of specified class If recursively is true, retrieving fields from all
   * class hierarchy
   *
   * @param clazz the class for which we want to get declared fields
   * @param recursively whether to search recursively up the super class chain
   * @return list of fields
   */
  public static Field[] getDeclaredFields(Class clazz, boolean recursively) {
    List fields = new LinkedList();
    Field[] declaredFields = clazz.getDeclaredFields();
    Collections.addAll(fields, declaredFields);

    Class superClass = clazz.getSuperclass();

    if (superClass != null && recursively) {
      Field[] declaredFieldsOfSuper = getDeclaredFields(superClass, recursively);
      if (declaredFieldsOfSuper.length > 0) {
        Collections.addAll(fields, declaredFieldsOfSuper);
      }
    }

    return fields.toArray(new Field[fields.size()]);
  }

  /**
   * Retrieving fields list of specified class and which are annotated by incoming annotation class
   * If recursively is true, retrieving fields from all class hierarchy
   *
   * @param clazz the class for which we want to get declared fields
   * @param annotationClass - specified annotation class
   * @param recursively whether to search recursively up the super class chain
   * @return list of annotated fields
   */
  public static Field[] getAnnotatedDeclaredFields(
      Class clazz, Class annotationClass, boolean recursively) {
    Field[] allFields = getDeclaredFields(clazz, recursively);
    List annotatedFields = new LinkedList();

    for (Field field : allFields) {
      if (field.isAnnotationPresent(annotationClass)) {
        annotatedFields.add(field);
      }
    }

    return annotatedFields.toArray(new Field[annotatedFields.size()]);
  }

  public static List