Page Comparison

package com.example.util;

import java.io.IOException;
import java.util.Collection;
import java.util.Locale;
import java.util.logging.Level;
import java.util.logging.Logger;

import com.fasterxml.jackson.databind.ObjectMapper;

import net.sourceforge.stripes.validation.TypeConverter;

@SuppressWarnings("rawtypes")
public class JsonTypeConverter implements TypeConverter {

  @Override
  public void setLocale(Locale locale) {
    // nothing to do
  }

  @SuppressWarnings("unchecked")
  @Override
  public Object convert(String string, Class type, Collection clctn) {
    ObjectMapper mapper = new ObjectMapper();
    try {
      return mapper.readValue(string, type);
    }
    catch (IOException ex) {
      Logger.getLogger(JsonTypeConverter.class.getName()).log(Level.SEVERE, null, ex);
    }
    return null;
  }
}

package com.example.util;

import java.io.IOException;

import javax.servlet.http.HttpServletResponse;

import org.apache.commons.lang3.Validate;
import org.apache.commons.logging.LogFactory;

import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.SerializationFeature;
import com.fasterxml.jackson.databind.ser.FilterProvider;
import com.fasterxml.jackson.databind.ser.impl.SimpleBeanPropertyFilter;
import com.fasterxml.jackson.databind.ser.impl.SimpleFilterProvider;
import com.example.util.LogUtil;

import net.sourceforge.stripes.action.StreamingResolution;

/**
 * The default response to a web service which {@link JsonReply replys} with {@link StreamingResolution streaming} JSON using a Jackson {@link ObjectMapper}.
 */
public class JsonResolution extends AbstractJsonResolution {

  private static final LogUtil LOG = LogUtil.getInstance(LogFactory.getLog(JsonResolution.class));

  private final JsonReply reply;

  public JsonResolution(JsonReply reply) {
    super();
    Validate.notNull(reply);
    this.reply = reply;
  }

  @Override
  public void stream(HttpServletResponse response) {
    Validate.notNull(response);
    LOG.trace("Replying with: ", reply.getClass().getSimpleName(), " : ", reply);

    ObjectMapper mapper = new ObjectMapper();
    if (reply instanceof EmptyReply) {
      mapper.configure(SerializationFeature.FAIL_ON_EMPTY_BEANS, false);
    }
    try {
      if (reply instanceof FilterableJsonReply) { // ignore specific fields
        String[] nonFilteredFields = ((FilterableJsonReply) reply).getNonFilteredFields();
        FilterProvider filters = new SimpleFilterProvider().addFilter("filter", SimpleBeanPropertyFilter.filterOutAllExcept(nonFilteredFields));
        mapper.writer(filters).writeValue(response.getOutputStream(), reply);
      }
      else { // write full content
        mapper.writeValue(response.getOutputStream(), reply);
      }
    }
    catch (IOException e) {
      LOG.error(e);
    }
  }
}