json jackson marshalling unmarshalling using jaxb annotations with indenting output

package util;

import java.io.StringReader;
import java.io.StringWriter;

import org.codehaus.jackson.map.AnnotationIntrospector;
import org.codehaus.jackson.map.ObjectMapper;
import org.codehaus.jackson.map.SerializationConfig;
import org.codehaus.jackson.map.SerializationConfig.Feature;
import org.codehaus.jackson.xc.JaxbAnnotationIntrospector;

public class JsonMapper {
 Class parameterizedClass;

 public JsonMapper(Class x) {
  this.parameterizedClass = x;
 }

 public T fromJson(String str) {
  if (str == null) {
   return null;
  }
  ObjectMapper mapper = new ObjectMapper();
  AnnotationIntrospector introspector = new JaxbAnnotationIntrospector();
  // make deserializer use JAXB annotations (only)
  mapper.getDeserializationConfig().setAnnotationIntrospector(introspector);
  try {
   T readValue = mapper.readValue(new StringReader(str), parameterizedClass);
   return readValue;
  } catch (Exception e) {
   throw new RuntimeException(e);
  }
 }

 public String toJson(T jaxbObject) {
  if (jaxbObject == null) {
   return "null";
  }
  ObjectMapper mapper = new ObjectMapper();
  AnnotationIntrospector introspector = new JaxbAnnotationIntrospector();
  // make deserializer use JAXB annotations (only)
  mapper.getDeserializationConfig().setAnnotationIntrospector(introspector);
  // make serializer use JAXB annotations (only)
  SerializationConfig serializationConfig = mapper.getSerializationConfig();
  serializationConfig.setAnnotationIntrospector(introspector);
  serializationConfig.set(Feature.INDENT_OUTPUT, true);
  StringWriter stringWriter = new StringWriter();
  try {
   mapper.writeValue(stringWriter, jaxbObject);
  } catch (Exception e) {
   throw new RuntimeException(e);
  }
  String str = stringWriter.toString();
  return str;
 }
}