有效地使用JSON流(使用Java) [英] Working with JSON streams efficiently (in Java)
问题描述
我一直在使用 JSONObject 和 JSONReader ,但理想情况下我正在寻找混合动力:)
I've been using both JSONObject and JSONReader, but ideally I'm looking for a hybrid :)
特别是,给定一个JSON对象流,任意长的JSON数组的一部分,是否有一个帮助器/库,一次产生JSONObject,迭代器样式,而不是读取所有内容或必须解析单个原始字段(JsonReader)?
In particular, given a stream of JSON objects, part of arbitrarily long JSON array, is there a helper/library that yields "JSONObject" at a time, iterator style, instead of reading everything in or having to parse out individual primitive fields (JsonReader)?
假设API的示例:
JsonReader reader = new JsonReader(new InputStreamReader(in, "UTF-8"));
reader.beginArray();
while (reader.hasNext())
{
JSONObject obj = reader.readObject();
// do something with 'obj'
}
reader.endArray();
上面,调用readObject解析一些复杂的JSON子树并将其作为JSONObject返回。
Above, calling readObject parses some complex JSON sub-tree and returns it as JSONObject.
推荐答案
javax.json.JSONParser
打印出json的示例:
There's the javax.json.JSONParser
An example that prints out a json:
import javax.json.Json;
import javax.json.stream.JsonParser;
...
JsonParser parser = Json.createParser(new StringReader(jsonData));
while (parser.hasNext()) {
JsonParser.Event event = parser.next();
switch(event) {
case START_ARRAY:
case END_ARRAY:
case START_OBJECT:
case END_OBJECT:
case VALUE_FALSE:
case VALUE_NULL:
case VALUE_TRUE:
System.out.println(event.toString());
break;
case KEY_NAME:
System.out.print(event.toString() + " " +
parser.getString() + " - ");
break;
case VALUE_STRING:
case VALUE_NUMBER:
System.out.println(event.toString() + " " +
parser.getString());
break;
}
}
来自 http://docs.oracle.com/javaee/7/tutorial/doc/jsonp004.htm#BABDBHIA
它是JavaEE7 api的一部分,但可以从 https获取一个独立的jar: //jsonp.java.net/download.html
这篇关于有效地使用JSON流(使用Java)的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持IT屋!