I am dealing with json data fetched from twitter API
on PHP I normally do something like:
$data = json_decode($response);
and the $data would be STD class object
I want to do the same thing in Java.
I took a look at Gson, but I need a second argument which seems like I need to create a specific class for the fetched data.
The basic question is how can I convert JSON to Standard Java Object like in PHP (STD Class Object)
Thank You
Read it into a map using Jackson then you can access whatever data you want. For instance, if your json looks like this
{ "name":"blah",
"address": {
"line1": "1234 my street",
"city": "my city",
"state": "my state"
}
}
Then you could:
ObjectMapper mapper = new ObjectMapper();
Map<String, Object> mystuff = mapper.readValue( jsonString, Map.class );
String name = (String)mystuff.get("name");
String city = ((Map<String, Object>)mystuff.get( "address" )).get( "city" );
If your JSON data does not follow a specific structure, don't use GSON, but a regular JSON library (like the one from json.org) that will give you an instance of a class like JSONObject, from which you can access data like jsonObject.getString("key").
jsonObject.getObject("key"). Read the javadocs.
There is no standard class object in Java and thus you need a class. You could dynamically create and compile the class at runtime but I doubt that's worth the trouble.
When json_encode doesn't exist on a PHP server, I use this:
<?php
if (!function_exists('json_encode'))
{
function json_encode($a=false)
{
if (is_null($a)) return 'null';
if ($a === false) return 'false';
if ($a === true) return 'true';
if (is_scalar($a))
{
if (is_float($a))
{
// Always use "." for floats.
return floatval(str_replace(",", ".", strval($a)));
}
if (is_string($a))
{
static $jsonReplaces = array(array("\\", "/", "\n", "\t", "\r", "\b", "\f", '"'), array('\\\\', '\\/', '\\n', '\\t', '\\r', '\\b', '\\f', '\"'));
return '"' . str_replace($jsonReplaces[0], $jsonReplaces[1], $a) . '"';
}
else
return $a;
}
$isList = true;
for ($i = 0, reset($a); $i < count($a); $i++, next($a))
{
if (key($a) !== $i)
{
$isList = false;
break;
}
}
$result = array();
if ($isList)
{
foreach ($a as $v) $result[] = json_encode($v);
return '[' . join(',', $result) . ']';
}
else
{
foreach ($a as $k => $v) $result[] = json_encode($k).':'.json_encode($v);
return '{' . join(',', $result) . '}';
}
}
}
?>
If you could rewrite this in Java then it should to the trick for you.
Ref:(Dead link)http://snippets.dzone.com/posts/show/7487
