com.extjs.gxt.ui.client.js.JsonConverter.java Source code

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Here is the source code for com.extjs.gxt.ui.client.js.JsonConverter.java

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/*
 * Sencha GXT 2.3.1 - Sencha for GWT
 * Copyright(c) 2007-2013, Sencha, Inc.
 * licensing@sencha.com
 * 
 * http://www.sencha.com/products/gxt/license/
 */
package com.extjs.gxt.ui.client.js;

import java.util.ArrayList;
import java.util.Date;
import java.util.List;
import java.util.Map;

import com.extjs.gxt.ui.client.GXT;
import com.extjs.gxt.ui.client.core.FastMap;
import com.extjs.gxt.ui.client.data.ModelData;
import com.google.gwt.json.client.JSONArray;
import com.google.gwt.json.client.JSONBoolean;
import com.google.gwt.json.client.JSONNull;
import com.google.gwt.json.client.JSONObject;
import com.google.gwt.json.client.JSONParser;
import com.google.gwt.json.client.JSONString;
import com.google.gwt.json.client.JSONValue;

/**
 * Helper class to decode and encode objects to and from Json. Converter handles
 * simple data types (strings, numbers, booleans) and lists and maps.
 */
@SuppressWarnings("deprecation")
public class JsonConverter {

    /**
     * Decodes a Json string into a map.
     * 
     * @param jsonString the Json string
     * @return the map
     */
    public static Map<String, Object> decode(String jsonString) {
        JSONValue v = JSONParser.parse(jsonString);
        if (v.isObject() != null) {
            return decode(v.isObject());
        } else {
            return null;
        }
    }

    /**
     * Decodes a JSONObject to a map.
     * 
     * @param jso the JSONObject
     * @return the map
     */
    public static Map<String, Object> decode(JSONObject jso) {
        Map<String, Object> map = new FastMap<Object>();
        for (String key : jso.keySet()) {
            JSONValue j = jso.get(key);
            if (j.isObject() != null) {
                map.put(key, decode(j.isObject()));
            } else if (j.isArray() != null) {
                map.put(key, decodeToList(j.isArray()));
            } else if (j.isBoolean() != null) {
                map.put(key, j.isBoolean().booleanValue());
            } else if (j.isString() != null) {
                map.put(key, decodeValue(j.isString().stringValue()));
            }
        }
        return map;
    }

    /**
     * Encodes a map into a JSONObject.
     * 
     * @param map the map
     * @return the JSONObject
     */
    public static JSONObject encode(Map<String, Object> map) {
        return encodeMap((Map<String, Object>) map);
    }

    /**
     * Encodes a model data instance into a JSONObject.
     * 
     * @param model the model data object
     * @return the JSONObject
     */
    public static JSONObject encode(ModelData model) {
        return encodeMap(((ModelData) model).getProperties());
    }

    protected static Object decodeValue(String value) {
        try {
            if (value == null || value.length() < 3) {
                return null;
            }
            String type = value.substring(0, 2);
            String val = value.substring(2);
            if (type.equals("d:")) {
                long time = Long.parseLong(val);
                return new Date(time);
            } else if (type.equals("i:")) {
                return Integer.decode(val);
            } else if (type.equals("f:")) {
                return new Float(val);
            }
            return val;
        } catch (Exception e) {
            e.printStackTrace();
            return null;
        }
    }

    protected static List<Object> decodeToList(JSONArray array) {
        List<Object> list = new ArrayList<Object>();
        for (int i = 0; i < array.size(); i++) {
            JSONValue v = array.get(i);
            if (v.isObject() != null) {
                list.add(decode(v.isObject()));
            } else if (v.isArray() != null) {
                list.add(decodeToList(v.isArray()));
            } else if (v.isNull() != null) {
                list.add(null);
            } else if (v.isNumber() != null) {
                list.add(v.isNumber().doubleValue());
            } else if (v.isBoolean() != null) {
                list.add(v.isBoolean().booleanValue());
            } else if (v.isString() != null) {
                list.add(decodeValue(v.isString().stringValue()));
            }
        }

        return list;
    }

    protected static String encodeValue(Object value) {
        if (value instanceof Date) {
            return "d:" + ((Date) value).getTime();
        } else if (value instanceof Integer) {
            if (GXT.isIE10) {
                return "i:" + coerceInt(((Integer) value).intValue());
            }
            return "i:" + value;
        } else if (value instanceof Float) {
            return "f:" + value;
        }
        return "s:" + value.toString();
    }

    private static native int coerceInt(int value) /*-{
                                                   return ~~value;
                                                   }-*/;

    @SuppressWarnings("unchecked")
    protected static JSONObject encodeMap(Map<String, Object> data) {
        JSONObject jsobj = new JSONObject();
        for (String key : data.keySet()) {
            Object val = data.get(key);
            if (val instanceof String) {
                jsobj.put(key, new JSONString(encodeValue(val)));
            } else if (val instanceof Date) {
                jsobj.put(key, new JSONString(encodeValue(val)));
            } else if (val instanceof Number) {
                jsobj.put(key, new JSONString(encodeValue(val)));
            } else if (val instanceof Boolean) {
                jsobj.put(key, JSONBoolean.getInstance((Boolean) val));
            } else if (val == null) {
                jsobj.put(key, JSONNull.getInstance());
            } else if (val instanceof Map) {
                jsobj.put(key, encodeMap((Map<String, Object>) val));
            } else if (val instanceof List) {
                jsobj.put(key, encodeList((List<Object>) val));
            } else if (val instanceof ModelData) {
                jsobj.put(key, encodeMap(((ModelData) val).getProperties()));
            }
        }

        return jsobj;
    }

    @SuppressWarnings("unchecked")
    protected static JSONArray encodeList(List<Object> data) {
        JSONArray jsona = new JSONArray();
        for (int i = 0; i < data.size(); i++) {
            Object val = data.get(i);
            if (val instanceof ModelData) {
                jsona.set(i, encodeMap(((ModelData) val).getProperties()));
            } else if (val instanceof Map) {
                jsona.set(i, encodeMap((Map<String, Object>) val));
            } else if (val instanceof List) {
                jsona.set(i, encodeList((List<Object>) val));
            } else if (val instanceof String) {
                jsona.set(i, new JSONString(encodeValue(val)));
            } else if (val instanceof Number) {
                jsona.set(i, new JSONString(encodeValue(val)));
            } else if (val instanceof Boolean) {
                jsona.set(i, JSONBoolean.getInstance((Boolean) val));
            } else if (val == null) {
                jsona.set(i, JSONNull.getInstance());
            } else if (val instanceof Date) {
                jsona.set(i, new JSONString(encodeValue(val)));
            }
        }
        return jsona;
    }
}