package us.codecraft.webmagic.model.fields;
   
   import java.lang.reflect.InvocationTargetException;
   
   import org.slf4j.Logger;
   
   import us.codecraft.webmagic.model.FieldExtractor;
   import us.codecraft.webmagic.model.formatter.ObjectFormatter;
   
  public abstract class PageField {
     public abstract boolean operation(Object o, FieldExtractor fieldExtractor, Logger logger) throws IllegalAccessException, InvocationTargetException;
  
     protected Object convert(String value, ObjectFormatter objectFormatter, Logger logger) {
        try {
           Object format = objectFormatter.format(value);
           logger.debug("String {} is converted to {}", value, format);
           return format;
        } catch (Exception e) {
              logger.error("convert " + value + " to " + objectFormatter.clazz() + " error!", e);
        }
        return null;
     }
  
     protected void setField(Object o, FieldExtractor fieldExtractor, Object value) throws IllegalAccessException, InvocationTargetException {
        if (value != null) {
           if (fieldExtractor.getSetterMethod() != null)
              fieldExtractor.getSetterMethod().invoke(o, value);
           fieldExtractor.getField().set(o, value);
        }
     }
  }