UpdaterMapper.java

package net.minidev.json.writer;

import java.io.IOException;
import java.lang.reflect.Type;
import net.minidev.json.parser.ParseException;

public class UpdaterMapper<T> extends JsonReaderI<T> {
  final T obj;
  final JsonReaderI<?> mapper;

  public UpdaterMapper(JsonReader base, T obj) {
    super(base);
    if (obj == null) throw new NullPointerException("can not update null Object");
    this.obj = obj;
    this.mapper = (JsonReaderI<?>) base.getMapper(obj.getClass());
  }

  public UpdaterMapper(JsonReader base, T obj, Type type) {
    super(base);
    if (obj == null) throw new NullPointerException("can not update null Object");
    this.obj = obj;
    this.mapper = (JsonReaderI<?>) base.getMapper(type);
  }

  /** called when json-smart parser meet an object key */
  public JsonReaderI<?> startObject(String key) throws ParseException, IOException {
    Object bean = mapper.getValue(obj, key);
    if (bean == null) return mapper.startObject(key);
    return new UpdaterMapper<Object>(base, bean, mapper.getType(key));
  }

  /**
   * called when json-smart parser start an array.
   *
   * @param key the destination key name, or null.
   */
  public JsonReaderI<?> startArray(String key) throws ParseException, IOException {
    // if (obj != null)
    return mapper.startArray(key);
  }

  /** called when json-smart done parsing a value */
  public void setValue(Object current, String key, Object value)
      throws ParseException, IOException {
    // if (obj != null)
    mapper.setValue(current, key, value);
  }

  /** add a value in an array json object. */
  public void addValue(Object current, Object value) throws ParseException, IOException {
    // if (obj != null)
    mapper.addValue(current, value);
  }

  /** use to instantiate a new object that will be used as an object */
  public Object createObject() {
    if (obj != null) return obj;
    return mapper.createObject();
  }

  /** use to instantiate a new object that will be used as an array */
  public Object createArray() {
    if (obj != null) return obj;
    return mapper.createArray();
  }

  /**
   * Allow a mapper to convert a temporary structure to the final data format.
   *
   * <p>example: convert an List&lt;Integer&gt; to an int[]
   */
  @SuppressWarnings("unchecked")
  public T convert(Object current) {
    if (obj != null) return obj;
    return (T) mapper.convert(current);
  }
}