package liquibase.util.csv.opencsv.bean;
   
   import liquibase.util.csv.opencsv.CSVReader;
   
   import java.beans.BeanInfo;
   import java.beans.IntrospectionException;
   import java.beans.Introspector;
   import java.beans.PropertyDescriptor;
   import java.io.IOException;
  
  /**
   * Copyright 2007 Kyle Miller.
   * 
   * 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.
   */
  
  public class HeaderColumnNameMappingStrategy implements MappingStrategy {
      protected String[] header;
      protected PropertyDescriptor[] descriptors;
      protected Class type;
  
      public void captureHeader(CSVReader reader) throws IOException {
          header = reader.readNext();
      }
  
      public PropertyDescriptor findDescriptor(int col) throws IntrospectionException {
          String columnName = getColumnName(col);
          return (null != columnName && columnName.trim().length() > 0) ? findDescriptor(columnName) : null;
      }
  
      protected String getColumnName(int col) {
          return (null != header && col < header.length) ? header[col] : null;
      }
  
      protected PropertyDescriptor findDescriptor(String name) throws IntrospectionException {
          if (null == descriptors)
              descriptors = loadDescriptors(getType()); // lazy load descriptors
          for (int i = 0; i < descriptors.length; i++) {
              PropertyDescriptor desc = descriptors[i];
              if (matches(name, desc))
                  return desc;
          }
          return null;
      }
  
      protected boolean matches(String name, PropertyDescriptor desc) {
          return desc.getName().equals(name);
      }
  
      protected PropertyDescriptor[] loadDescriptors(Class cls) throws IntrospectionException {
          BeanInfo beanInfo = Introspector.getBeanInfo(cls);
          return beanInfo.getPropertyDescriptors();
      }
  
      public Object createBean() throws InstantiationException, IllegalAccessException {
          return type.newInstance();
      }
  
      public Class getType() {
          return type;
      }
  
      public void setType(Class type) {
          this.type = type;
      }
  }