如何使用 Java 在 JSON 中搜索/查找
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How to search/find In JSON with java
提问by Ssire
I have a below JSON string from the below i want to find/search criteria in JSON String.
我有一个下面的 JSON 字符串，我想在 JSON 字符串中查找/搜索条件。
1). To find the Number of keys present. 2). To get the values of given key(if we have array)
1）。找到存在的键数。2）。获取给定键的值（如果我们有数组）
{
"store": {
"book": [
{
"category": "reference",
"author": "Nigel Rees",
"title": "Sayings of the Century",
"price": 8.95
},
{
"category": "fiction",
"author": "Evelyn Waugh",
"title": "Sword of Honour",
"price": 12.99
},
{
"category": "fiction",
"author": "Herman Melville",
"title": "Moby Dick",
"isbn": "0-553-21311-3",
"price": 8.99
},
{
"category": "fiction",
"author": "J. R. R. Tolkien",
"title": "The Lord of the Rings",
"isbn": "0-395-19395-8",
"price": 22.99
}
],
"bicycle": {
"color": "red",
"price": 19.95
}
},
"expensive": 10
}
I am looking a solution like Groovy GPath Syntax
我正在寻找像 Groovy GPath Syntax 这样的解决方案
- store.book - size of this array.
- store.book[*].category - how may times the key present in the array.
- store.bicycle - if it found it has to return true value
- store.book - 此数组的大小。
- store.book[*].category - 数组中存在的键的次数。
- store.bicycle - 如果发现它必须返回真值
回答by Johan
You can also use the JsonPathproject provided by REST Assured. This JsonPath project uses Groovy GPath expressions. In Maven you can depend on it like this:
您还可以使用REST Assured提供的JsonPath项目。这个 JsonPath 项目使用 Groovy GPath 表达式。在 Maven 中，您可以像这样依赖它：
<dependency>
<groupId>com.jayway.restassured</groupId>
<artifactId>json-path</artifactId>
<version>2.4.0</version>
</dependency>
Examples:
例子：
To get a list of all book categories:
要获取所有书籍类别的列表：
List<String> categories = JsonPath.from(json).get("store.book.category");
Get the first book category:
获取第一个图书类别：
String category = JsonPath.from(json).get("store.book[0].category");
Get the last book category:
获取最后一本书类别：
String category = JsonPath.from(json).get("store.book[-1].category");
Get all books with price between 5 and 15:
获取价格在 5 到 15 之间的所有书籍：
List<Map> books = JsonPath.from(json).get("store.book.findAll { book -> book.price >= 5 && book.price <= 15 }");
GPath is very powerful and you can make use of higher order functions and all Groovy data structures in your path expressions.
GPath 非常强大，您可以在路径表达式中使用高阶函数和所有 Groovy 数据结构。
回答by David Michael Gang
I would try the following library
我会尝试以下库
https://github.com/jayway/JsonPath
https://github.com/jayway/JsonPath
gives you all books
给你所有的书
回答by Usman Yaqoob
First of all you have to add dependency
首先你必须添加依赖
<dependency>
<groupId>org.json</groupId>
<artifactId>json</artifactId>
<version>20090211</version>
</dependency>
Then you can use this code:
然后你可以使用这个代码：
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import org.json.XML;
public class Main {
public static int PRETTY_PRINT_INDENT_FACTOR = 4;
public static String TEST_XML_STRING =
"<Result><ResultParameters><ResultParameter><Key>TransEndDate</Key><Value>20170731</Value></ResultParameter><ResultParameter><Key>Failed Reason</Key><Value>Operator 03058361178058365278 has no permission to perform the Check Balance service.</Value></ResultParameter><ResultParameter><Key>TransEndTime</Key><Value>123611</Value></ResultParameter></ResultParameters><ResultCode>2000</ResultCode><ResultType>0</ResultType><OriginatorConversationID>S_X20130129210125</OriginatorConversationID><ResultDesc>Initiator authentication error.</ResultDesc><TransactionID>000749213589</TransactionID><ConversationID>AG_20170731_00004c28e51f1f822e9e</ConversationID></Result>";
public static void main(String[] args) {
try {
JSONObject xmlJSONObj = XML.toJSONObject(TEST_XML_STRING);
String jsonPrettyPrintString = xmlJSONObj.toString(PRETTY_PRINT_INDENT_FACTOR);
System.out.println(jsonPrettyPrintString);
System.out.println("Element="+xmlJSONObj.getJSONObject("Result").getInt("ResultCode"));
} catch (JSONException je) {
System.out.println(je.toString());
}
}
}
// in it i am searching an element which is present in a json object
