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Parse array in JSON using JsonPath in Java

I am using jayway JsonPath library to parse the JSON using the path given. I am able to get the string value if I give the correct path. But I want to get the list of maps when I give the path if its an array. For example, I have a JSON like below:
{
"employees": {
"company": "Google",
"people": [{
"name": "John",
"age": 25,
"location": "zurich"
},
{
"name": "Peter",
"age": 27,
"location": "Lucerene"
}]
}
}
Below is the code I am using to parse the json.
if I give the path $.employees.people, I am getting the String, But I need to List of Maps. Below is the code I am using to Parse Json using jsonpath.
DocumentContext documentContext = JsonPath.parse(jsonStr);
JsonPath jsonPath = JsonPath.compile("$.employees.people");
List<Maps<String,String>> jsonList = documentContext.read(jsonPath) //But this is returning String
Anyone suggest proper approach to get what I expected.

try using,
DocumentContext documentContext = JsonPath.parse(jsonStr);
JsonPath jsonPath = JsonPath.compile("$.employees.people[?]");
List<Maps<String,String>> jsonList = documentContext.read(jsonPath);
if you need more details. readmore...

How to convert a file to a String which is accepted in JSON?

I am trying to create gists in Github via REST ASSURED.
To create a gist a need to pass file names and their contents.
Now, the content of the file is something which is being rejected by the API.
Example:
{
"description": "Hello World Examples",
"public": true,
"files": {
"hello_world.rb": {
"content": "class HelloWorld\n def initialize(name)\n #name = name.capitalize\n end\n def sayHi\n puts \"Hello !\"\n end\nend\n\nhello = HelloWorld.new(\"World\")\nhello.sayHi"
},
"hello_world.py": {
"content": "class HelloWorld:\n\n def init(self, name):\n self.name = name.capitalize()\n \n def sayHi(self):\n print \"Hello \" + self.name + \"!\"\n\nhello = HelloWorld(\"world\")\nhello.sayHi()"
},
"hello_world_ruby.txt": {
"content": "Run ruby hello_world.rb to print Hello World"
},
"hello_world_python.txt": {
"content": "Run python hello_world.py to print Hello World"
}
}
This is how the the API wants the JSON to be, I could get this via my code:
{
"description": "Happy World",
"public": true,
"files": {
"sid.java": {
"content": "Ce4z5e22ta"
},
"siddharth.py": {
"content": "def a:
if sidh>kundu:
sid==kundu
else:
kundu==sid
"
}
}
}
So the change in the indentations is causing GitHUb API to fail this with 400 error. Can someone please help?

As pointed out in the comments, JSON does not allow control characters in strings. In the case of line breaks, these were encoded as \n in the example.
You should definitely consider using a proper library to create the JSON rather than handling the raw strings yourself.

Create a POJO which will represent your gist (i.e. object with fields like 'description', 'files' collection. And separate POJO for file containing string fields 'name' and 'content';
Do something like this to convert your gist:
try {
GistFile file new GistFile();// Assuming this is POJO for your file
//Set name and content
Gist gist = new Gist(); //Asuming this is a POJO for your gist
gist.addFile(file);
//Add more files if needed and set other properties
ObjectMapper mapper = new ObjectMapper();
String content = mapper.writeValueAsString(gist);
//Now you have valid JSON string
} catch (Exception e) {
e.printStackTrace();
}
This is for com.fasterxml.jackson.databind.ObjectMapper or use different JSON library
Actually there are GitHub specific libraries which do most of the job for you. Please refer to this question: How to connect to github using Java Program it might be helpful

EOF Exception using Jackson

I am using Jackson to parse an external file which contains json. The json in the file takes this form:
{
"timestamp": MY_TIMESTAMP,
"serial": "MY_SERIAL",
"data": [{
MY_DATA
}, {
MY_DATA
}]
}
The code I am trying to use to access this is as follows:
JsonNode root = mapper.readTree(dataFileLocation);
JsonNode data = root.get("data");
ArrayList<AriaInactiveExchange> exchangeList = mapper.readValue(data.toString(), new TypeReference<List<AriaInactiveExchange>>(){});
I have validated the location of the dataFile and the data in it. I'm positive that i'm doing something wrong and that this may not even be the right approach. But the idea is clear that I need to get to "data" and map that to an Array.
When this code is run the following line instantly throws an EOF exception:
JsonNode root = mapper.readTree(dataFileLocation);

java native JSON api for parsing

I've following JSON structure coming in,
{
"name": "product new",
"brand": {
"id": 1
},
"category": {
"id": 1
}
}
I can extract
jsonObject = Json.createReader(httpServletRequest.getInputStream()).readObject();
jsonObject.getString("name")
Errors:
jsonObject.getInt("brand.id")
jsonObject.getInt("category.id")
I'm using Java API for JSON.
Edit If I access
System.out.println(jsonObject.get("brand"));
// response {"id":1}
System.out.println(jsonObject.get("brand.id"));
// null
http://www.oracle.com/technetwork/articles/java/json-1973242.html

I don't think the API you're using supports nested expressions. You'll need to access the parent object, and then the specific field:
System.out.println(jsonObject.getJsonObject("brand").getInt("id"));
Or you can use an API that accepts a path expression, like Jackson:
JsonNode node = new ObjectMapper().readTree(httpServletRequest.getInputStream());
System.out.println(node.at("/brand/id").asInt());

How to create JSON Schema for Name/Value structure?

My problem is that i am serializing the content of map to JSON.
In the output (JSON), i have object that follow key/name syntax rule.
The key is created from map key, and the name from the value.
Model Example:
class Storage {
Map<String,String> values = new HashMap<>();
{
map.put("key1","key1");
map.put("key2","key2");
map.put("key3","key3");
}
}
JSON Example object:
{
key1=value1,
key2=value2,
key3=value3
}
JSON Schema:
{
"name": "storage",
"description": "Store of key values",
"properties": {
// How can we describe the properties if we do not know the name ?
}
}
The issue is that i do not know what the values will be but i know that they will be some.
Can you help me to provide me the full definition of schema?
Disclaimer:
I know that this can be also serialized as
{
values: [
{key="key1", value="value1"},
{key="key2", value="value2"},
{key="key3", value="value3"}
]
}
but is do not want to have array in the JSON.

Assuming your validator supports it you can use patternProperties.
For the schema...
{
"title": "Map<String,String>",
"type": "object",
"patternProperties": {
".{1,}": { "type": "string" }
}
}
...and the document...
{
"foo":"bar",
"baz":1
}
...the value of property foo is valid because it is a string but baz fails validation because it is a number.

I used the Solution suggested by #augurar
"additionalProperties": { "type": "string" }
for AWS API Gateway Model .... and the SDK was able to generate the Map variable as required in Java / Android SDK
#Arne Burmeister - in my case - Solution 1 didnt worked as needed - although it didnt gave any error in the Model (Schema Created)