/*
* Ext GWT 2.2.4 - Ext for GWT
* Copyright(c) 2007-2010, Ext JS, LLC.
* licensing@extjs.com
*
* http://extjs.com/license
*/
package com.extjs.gxt.ui.client.data;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;
import com.google.gwt.core.client.JavaScriptObject;
import com.google.gwt.i18n.client.DateTimeFormat;
import com.google.gwt.json.client.JSONArray;
import com.google.gwt.json.client.JSONObject;
import com.google.gwt.json.client.JSONParser;
import com.google.gwt.json.client.JSONValue;
/**
* A <code>DataReader</code> implementation that reads JSON data using a
* <code>ModelType</code> definition and produces a set of
* <code>ModelData</code> instances.
*
* <p />
* Subclasses can override {@link #createReturnData(Object, List, int)} to
* control what object is returned by the reader. Subclass may override
* {@link #newModelInstance()} to return any model data subclass.
*
* @param <D> the <code>ListLoadResult</code> type being returned by the reader
*/
@SuppressWarnings("deprecation")
public class JsonReader<D> implements DataReader<D> {
private ModelType modelType;
/**
* Creates a new JSON reader.
*
* @param modelType the model type definition
*/
public JsonReader(ModelType modelType) {
this.modelType = modelType;
}
@SuppressWarnings({"unchecked", "rawtypes"})
public D read(Object loadConfig, Object data) {
JSONObject jsonRoot = null;
if (data instanceof JavaScriptObject) {
jsonRoot = new JSONObject((JavaScriptObject) data);
} else {
jsonRoot = (JSONObject) JSONParser.parse((String) data);
}
JSONArray root = (JSONArray) jsonRoot.get(modelType.getRoot());
int size = root.size();
ArrayList<ModelData> models = new ArrayList<ModelData>();
for (int i = 0; i < size; i++) {
JSONObject obj = (JSONObject) root.get(i);
ModelData model = newModelInstance();
for (int j = 0; j < modelType.getFieldCount(); j++) {
DataField field = modelType.getField(j);
String name = field.getName();
Class type = field.getType();
String map = field.getMap() != null ? field.getMap() : field.getName();
JSONValue value = obj.get(map);
if (value == null) continue;
if (value.isArray() != null) {
// nothing
} else if (value.isBoolean() != null) {
model.set(name, value.isBoolean().booleanValue());
} else if (value.isNumber() != null) {
if (type != null) {
Double d = value.isNumber().doubleValue();
if (type.equals(Integer.class)) {
model.set(name, d.intValue());
} else if (type.equals(Long.class)) {
model.set(name, d.longValue());
} else if (type.equals(Float.class)) {
model.set(name, d.floatValue());
} else {
model.set(name, d);
}
} else {
model.set(name, value.isNumber().doubleValue());
}
} else if (value.isObject() != null) {
// nothing
} else if (value.isString() != null) {
String s = value.isString().stringValue();
if (type != null) {
if (type.equals(Date.class)) {
if ("timestamp".equals(field.getFormat())) {
Date d = new Date(Long.parseLong(s) * 1000);
model.set(name, d);
} else {
DateTimeFormat format = DateTimeFormat.getFormat(field.getFormat());
Date d = format.parse(s);
model.set(name, d);
}
}
} else {
model.set(name, s);
}
} else if (value.isNull() != null) {
model.set(name, null);
}
}
models.add(model);
}
int totalCount = models.size();
if (modelType.getTotalName() != null) {
totalCount = getTotalCount(jsonRoot);
}
return (D) createReturnData(loadConfig, models, totalCount);
}
/**
* Responsible for the object being returned by the reader.
*
* @param loadConfig the load config
* @param records the list of models
* @param totalCount the total count
* @return the data to be returned by the reader
*/
@SuppressWarnings("unchecked")
protected Object createReturnData(Object loadConfig, List<ModelData> records,
int totalCount) {
return (D) records;
}
protected int getTotalCount(JSONObject root) {
if (modelType.getTotalName() != null) {
JSONValue v = root.get(modelType.getTotalName());
if (v != null) {
if (v.isNumber() != null) {
return (int) v.isNumber().doubleValue();
} else if (v.isString() != null) {
return Integer.parseInt(v.isString().stringValue());
}
}
}
return -1;
}
/**
* Returns the new model instances. Subclasses may override to provide an
* model data subclass.
*
* @return the new model data instance
*/
protected ModelData newModelInstance() {
return new BaseModelData();
}
}