I am facing a problem creating a Json which is actually a complex one and i need to create it through HashMap only..I was actually looking for some recursive function that could be a best solution to my problem.
JSON i need to create looks like..
{"pkt":{
"data2":{"z":"3", "y":"2", "x":"1"},
"data3":{"n":"3", "l":"1", "m":"2"},
"mid":"1328779096525",
"data1":{"b":"2", "c":"3", "a":"1"},
"msg":"10012"
}
}
any ideas??
You'd do something like this:
public void toJSON(Map<?, ?> map, JSONStringer stringer) throws JSONException {
stringer.object();
for (Map.Entry<?, ?> entry : map.entrySet()) {
stringer.key(String.valueOf(entry.getKey()));
toJSONValue(entry.getValue(), stringer);
}
stringer.endObject();
}
public void toJSONValue(Object value, JSONStringer stringer) throws JSONException {
if (value == null) {
stringer.value(null);
} else if (value instanceof Collection) {
toJSON((Collection<?>) value, stringer);
} else if (value instanceof Map) {
toJSON((Map<?, ?>) value, stringer);
} else if (value.getClass().isArray()) {
if (value.getClass().getComponentType().isPrimitive()) {
stringer.array();
if (value instanceof byte[]) {
for (byte b : (byte[]) value) {
stringer.value(b);
}
} else if (value instanceof short[]) {
for (short s : (short[]) value) {
stringer.value(s);
}
} else if (value instanceof int[]) {
for (int i : (int[]) value) {
stringer.value(i);
}
} else if (value instanceof float[]) {
for (float f : (float[]) value) {
stringer.value(f);
}
} else if (value instanceof double[]) {
for (double d : (double[]) value) {
stringer.value(d);
}
} else if (value instanceof char[]) {
for (char c : (char[]) value) {
stringer.value(c);
}
} else if (value instanceof boolean[]) {
for (boolean b : (boolean[]) value) {
stringer.value(b);
}
}
stringer.endArray();
} else {
toJSON((Object[]) value, stringer);
}
} else {
stringer.value(value);
}
}
public void toJSON(Object[] array, JSONStringer stringer) throws JSONException {
stringer.array();
for (Object value : array) {
toJSONValue(value, stringer);
}
stringer.endArray();
}
public void toJSON(Collection<?> collection, JSONStringer stringer) throws JSONException {
stringer.array();
for (Object value : collection) {
toJSONValue(value, stringer);
}
stringer.endArray();
}
To construct the example you gave:
// Using a variety of maps since all should work..
HashMap<String, Object> pkt = new HashMap<String, Object>();
LinkedHashMap<String, String> data1 = new LinkedHashMap<String, String>();
data1.put("b", "2");
data1.put("c", "3");
data1.put("a", "1");
LinkedHashMap<String, String> data2 = new LinkedHashMap<String, String>();
data2.put("z", "3");
data2.put("y", "2");
data2.put("x", "1");
TreeMap<String, Object> data3 = new TreeMap<String, Object>();
data3.put("z", "3");
data3.put("y", "2");
data3.put("x", "1");
pkt.put("data2", data2);
pkt.put("data3", data3);
pkt.put("mid", "1328779096525");
pkt.put("data1", data1);
pkt.put("msg", "10012");
try {
JSONStringer stringer = new JSONStringer();
stringer.object();
stringer.key("pkt");
toJSON(pkt, stringer);
stringer.endObject();
System.out.println(stringer.toString());
} catch (JSONException e) {
// Time for some error-handling
}
Which would result in (formatted for viewing):
{
"pkt":{
"data2":{
"z":"3",
"y":"2",
"x":"1"
},
"mid":"1328779096525",
"data3":{
"x":"1",
"y":"2",
"z":"3"
},
"msg":"10012",
"data1":{
"b":"2",
"c":"3",
"a":"1"
}
}
}
