在java中解析递归未知的json输入结构

我试图在java中解析递归未知的json输入结构，如下面的格式，并尝试在另一个json中重写相同的结构。

同时我需要在解析时validation每个json键/值。

{"Verbs":[{ "aaaa":"30d", "type":"ed", "rel":1.0, "id":"80", "spoken":"en", "ct":"on", "sps":null },{ "aaaa":"31", "type":"cc", "rel":3.0, "id":"10", "spoken":"en", "ct":"off", "sps":null },{ "aaaa":"81", "type":"nn", "rel":3.0, "id":"60", "spoken":"en", "ct":"on", "sps":null }]} 

请建议我可以使用哪个json解析器来读取和编写未知的json内容。

Answer 1

这样您就可以递归地解析JSON对象：

 import com.eclipsesource.json.JsonArray; import com.eclipsesource.json.JsonObject; import com.eclipsesource.json.JsonValue; public class JsonQuestion { public static void main(String[] args) { String input = "{\"Verbs\":[{\n" + " \"aaaa\":\"30d\", \"type\":\"ed\", \"rel\":1.0, \"id\":\"80\", \"spoken\":\"en\", \"ct\":\"on\", \"sps\":null\n" + "},{\n" + " \"aaaa\":\"31\", \"type\":\"cc\", \"rel\":3.0, \"id\":\"10\", \"spoken\":\"en\", \"ct\":\"off\", \"sps\":null\n" + "},{\n" + " \"aaaa\":\"81\", \"type\":\"nn\", \"rel\":3.0, \"id\":\"60\", \"spoken\":\"en\", \"ct\":\"on\", \"sps\":null\n" + "}]}"; JsonObject jsonObject = JsonObject.readFrom(input); handleObject(jsonObject); } private static void handleValue(JsonObject.Member member, JsonValue value) { if (value.isArray()) { if (member != null) { System.out.print("name = " + member.getName()); } System.out.println("array value "); recurseArray(value.asArray()); } else if (value.isBoolean()) { if (member != null) { System.out.print("name = " + member.getName()); } System.out.println(", boolean value = " + value.asBoolean()); } else if (value.isNull()) { if (member != null) { System.out.print("name = " + member.getName()); } System.out.println(", null value"); } else if (value.isNumber()) { if (member != null) { System.out.print("name = " + member.getName()); } System.out.println(", number value = " + value.asDouble()); } else if (value.isObject()) { if (member != null) { System.out.print("name = " + member.getName()); } System.out.println(", object value "); handleObject(value.asObject()); } else if (value.isString()) { if (member != null) { System.out.print("name = " + member.getName()); } System.out.println(", string value = " + value.asString()); } } private static void handleObject(JsonObject object) { for (JsonObject.Member next : object) { JsonValue value = next.getValue(); handleValue(next, value); } } private static void recurseArray(JsonArray array) { for (JsonValue value : array) { handleValue(null, value); } } } 

Answer 2

使用gson库https://sites.google.com/site/gson/gson-user-guide

 public void parseJson() { String jsonStr = "";//nput json String. JsonElement jsonElement = parser.parse(jsonStr); processJsonElement(jsonElement); } private void processJsonElement(JsonElement e) { if (e.isJsonArray()) { processJsonArray(e.getAsJsonArray()); } else if (e.isJsonNull()) { processJsonNull(e.getAsJsonNull()); } else if (e.isJsonObject()) { processJsonObject(e.getAsJsonObject()); } else if (e.isJsonPrimitive()) { processJsonPrimitive(e.getAsJsonPrimitive()); } } private void processJsonArray(JsonArray a) { for (JsonElement e : a) { processJsonElement(e); } } private void processJsonNull(JsonNull n) { System.out.println("null || : " + n); } private void processJsonObject(JsonObject o) { Set> members= o.entrySet(); for (Map.Entry e : members) { System.out.println("Processing object member: " + e.getKey()); processJsonElement(e.getValue()); } } private void processJsonPrimitive(JsonPrimitive p) { System.out.println("Primitive || :" + p); } 

或jackson

 public void processJson() { ObjectMapper objectMapper = new ObjectMapper(); try { JsonNode node = objectMapper.readTree(jsonStr); System.out.println(node); processNode(node); } catch (IOException e) { throw new RuntimeException(e); } } private void processNode(JsonNode n) { if (n.isContainerNode()) { processJsonContainer(n.iterator()); } else if (n.isNull()) { System.out.println("Null || :" + n); } else if (n.isNumber()) { System.out.println("Number || :" + n.asDouble()); } else if (n.isBoolean()) { System.out.println("Boolean || :" + n.asBoolean()); } else if (n.isTextual()) { System.out.println("Text || :" + n.asText()); } } private void processJsonContainer(Iterator iterator) { while (iterator.hasNext()) { processNode(iterator.next()); } } 

Answer 3

使用Jackson库，您可以这样做，例如，以这种方式：

 ObjectMapper mapper = new ObjectMapper(); JsonNode rootNode = mapper.readTree(json); ArrayNode verbs = (ArrayNode) rootNode.get("Verbs"); int size = verbs.size(); for (int index = 0; index < size; index++) { JsonNode itemNode = verbs.get(index); System.out.println(itemNode); System.out.println(itemNode.get("aaaa").asText()); System.out.println(itemNode.get("type").asText()); System.out.println(itemNode.get("rel").asInt()); System.out.println(itemNode.get("id").asInt()); //... }