JsonObject存入顺序和输出顺序不一样问题

##JsonObject的输入顺序和输出顺序不一样问题 ###问题原因在于JsonObject的默认实现的是用HashMap,所以我们得把他的构造函数用LinkedHashMap重写

• 好像是可以修改JsonObject的源码的构造函数，但我没试过，也不建议这么做。

• 我的方法是继承JsonObject类，然后重写构造方法。

  public class MyJSONObject extends JSONObject { private LinkedHashMap<Object, Object> mHashMap;

  1public MyJSONObject() {
  2    mHashMap = new LinkedHashMap<Object, Object>();
  3}
  4
  5@Override
  6public JSONObject put(String name, boolean value) throws JSONException {
  7    // TODO Auto-generated method stub
  8    return put(name, value);
  9}
  10
  11@Override
  12public JSONObject put(String name, double value) throws JSONException {
  13    // TODO Auto-generated method stub
  14    return put(name, value);
  15}
  16
  17@Override
  18public JSONObject put(String name, int value) throws JSONException {
  19    // TODO Auto-generated method stub
  20    return put(name, value);
  21}
  22
  23@Override
  24public JSONObject put(String name, long value) throws JSONException {
  25    // TODO Auto-generated method stub
  26    return put(name, value);
  27}
  28
  29public JSONObject put(String key, Object value) throws JSONException {
  30    if (key == null) {
  31        throw new JSONException("Null key.");
  32    }
  33    if (value != null) {
  34        testValidity(value);
  35        mHashMap.put(key, value);
  36    } else {
  37        remove(key);
  38    }
  39    return this;
  40}
  41
  42public String  getKey(String key) throws JSONException{
  43    return mHashMap.get(key).toString();
  44}
  45
  46public Object remove(String key) {
  47    return mHashMap.remove(key);
  48}
  49
  50static void testValidity(Object o) throws JSONException {
  51    if (o != null) {
  52        if (o instanceof Double) {
  53            if (((Double) o).isInfinite() || ((Double) o).isNaN()) {
  54                throw new JSONException("JSON does not allow non-finite numbers.");
  55            }
  56        } else if (o instanceof Float) {
  57            if (((Float) o).isInfinite() || ((Float) o).isNaN()) {
  58                throw new JSONException("JSON does not allow non-finite numbers.");
  59            }
  60        }
  61    }
  62}
  63
  64public String toString() {
  65    try {
  66        Iterator<Object> keys = mHashMap.keySet().iterator();
  67        StringBuffer sb = new StringBuffer("{");
  68
  69        while (keys.hasNext()) {
  70            if (sb.length() > 1) {
  71                sb.append(',');
  72            }
  73            Object o = keys.next();
  74            sb.append(quote(o.toString()));
  75            sb.append(':');
  76            sb.append(valueToString(mHashMap.get(o)));
  77        }
  78        sb.append('}');
  79        return sb.toString();
  80    } catch (Exception e) {
  81        return null;
  82    }
  83}
  84
  85static String valueToString(Object value) throws JSONException {
  86    if (value == null || value.equals(null)) {
  87        return "null";
  88    }
  89    if (value instanceof JSONStringer) {
  90        Object o;
  91        try {
  92            o = ((JSONStringer) value).toString();
  93        } catch (Exception e) {
  94            throw new JSONException(e.getMessage());
  95        }
  96        if (o instanceof String) {
  97            return (String) o;
  98        }
  99        throw new JSONException("Bad value from toJSONString: " + o);
  100    }
  101    if (value instanceof Number) {
  102        return numberToString((Number) value);
  103    }
  104    if (value instanceof Boolean || value instanceof JSONObject || value instanceof JSONArray) {
  105        return value.toString();
  106    }
  107    if (value instanceof Map) {
  108        return new JSONObject((Map) value).toString();
  109    }
  110    if (value instanceof Collection) {
  111        return new JSONArray((Collection) value).toString();
  112    }
  113    return quote(value.toString());
  114}
  

  }