I am trying to read an object into my model using objectMapper
ObjectMapper objectMapper = new ObjectMapper();
result = objectMapper.readValue(process.getData(), params.class);
under one of the keys of params there is a string
href=\"${organizationParams.get(\"info.facebook\")}\">
so after readValue happens the string looks like
href="${organizationParams.get("info.facebook")}">
and then later on I have call to Jsoup.clean() which truncates the string to
href="${organizationParams.get("
This is not desirable. Any ideas on how to retain the string after Jsoup.clean?
Related
I am trying to extract a value of predefined type (Boolean, Integer, joda.DateTime) from an arbitrary json that is sent as a String.
Eg: {"node1":{"node2":"2019-01-01T05:00:00.000Z"}}} and say I know that the value in this Json is a DateTime and I can extract the value 2019-01-01T05:00:00.000Z from this Json and disabled SerializationFeature.WRITE_DATES_AS_TIMESTAMPS.
When I try to serialize a simple String representation "1972-12-28T12:00:01.000Z" of org.joda.time.DateTime, it fails with JsonParseException: Unexpected character. However serialization will succeed for Booleans or DateTime string inside a TextNode.
I have have registered com.fasterxml.jackson.datatype.joda.JodaModule with my object mapper.
I have tried a few things, see the Junit test below
public class Tester {
public static class Bean {
public void Bean(){}
public DateTime start;
}
#Test
public void testJodaJsonSerialization() throws Exception{
ObjectMapper objectMapper = new ObjectMapper();
objectMapper.disable(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS);
objectMapper.registerModule(new JodaModule());
final String INPUT_JSON = "{\"start\" : \"1972-12-28T12:00:01.000Z\"}";
Bean bean = objectMapper.readValue(INPUT_JSON, Bean.class);
assertNotNull(bean.start);
System.out.println(objectMapper.writeValueAsString(bean)); //serializing as part of an object works
String boolAsString = "true";
Boolean aBoolean = objectMapper.readValue(boolAsString, Boolean.class); //works for bool (simple type)
System.out.println(aBoolean);
String dateAsTextNode = objectMapper.writeValueAsString(new TextNode("1972-12-28T12:00:01.000Z")); //works for TextNode
System.out.println("dateAsTextNode: " + dateAsTextNode);
DateTime dateTime = objectMapper.readValue(dateAsTextNode, DateTime.class);
System.out.println(dateTime);
JsonNode jsonRoot = objectMapper.readTree(INPUT_JSON);
String datetimeAsString = jsonRoot.get("start").asText();
objectMapper.readValue(objectMapper.writeValueAsString(new TextNode(datetimeAsString)), DateTime.class); //this workaround will work
objectMapper.readValue(objectMapper.writeValueAsString(new TextNode(boolAsString)), Boolean.class);
String dateAsString = "1972-12-28T12:00:01.000Z";
objectMapper.readValue(dateAsString, DateTime.class); //but this fails
}
}
I expect String serialization to work just like it does on the TextNode
Your String
String dateAsString = "1972-12-28T12:00:01.000Z";
contains the content
1972-12-28T12:00:01.000Z
which is not valid JSON, so Jackson cannot parse it.
It would be valid JSON if it contained leading quotes, so
String dateAsString = "\"1972-12-28T12:00:01.000Z\"";
and then parsing would succeed.
You can configure the pattern of the date format on the ObjectMapper level:
Value dateFormat = Value.forShape(Shape.STRING)
.withPattern("MM/dd/yyyy HH:mm:ss")
.withTimeZone(TimeZone.getTimeZone("UTC"));
ObjectMapper mapper = new ObjectMapper();
mapper.configure(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS, false)
.registerModule(new Jdk8Module())
.registerModule(new JavaTimeModule())
.configOverride(DateTime.class).setFormat(dateFormat);
I am getting a JSON string and want to print Name values on the console via JSP. Can someone suggest how to do it?
String AllCustomLockingCriterias = '{"TemplateArray":[{"Id":16,"Name":"Machine","type":"PM"},
{"Id":17,"Name":"Ethernet","type":"PM"},
{"Id":18,"Name":"Hard Disk","type":"PM"}]}';
Output I need:
Machine
Ethernet
Hard Disc
I want to start a loop and my output will be:
Machine
Ethernet
Hard Disc
use Gson jar package(produced by google.com) , FastJson(produced by alibaba.com) or jackson to serialize or deserialize the json string and the Class object.One jar package is enough.
use maven pom dependency/gradle config to add the gson to your project or add the gson jar into your lib folder directly,it is all up to you, maven is preferred.
define the Java Class field member,with the meta info from your json string,such as 'id','name','type'.The Java Class can be named 'Template'(do not forget to implement the java Serializable interface).
code example:
Gson gson = new Gson();
TypeToken typeToken = new TypeToken<List<Template>>() {};
Type type = typeToken.getType();
List<Template> templates = gson.fromJson(json, type);
return the templates list to the front jsp page within the jsp page scope.
if you user springMVC framework,you can add a model param to the method params,
#RequestMapping(value = "/test",method = RequestMethod.GET)
public String test(Model model){
model.addAttribute("templates",templates);
return "jspFileName";
}
for jsp site,you can use jsp EL Express to show the list
<c:forEach items="${templates}" var = "template">
${template.name}
</c:forEach>
the last but the most easy method is ,you can pass the json string to the jsp page.on the other words,do not need to serialize the json string to class,just pass the string to the jsp with the model attribute provided by springMVC or even the basic Servlet.And then use the javascript method to handle the json string.for example,
var obj = JSON.parse(json);
var array = obj.TemplateArray;
array.foreach(function(item) {
console.log(item.name);
});
"fasterxml" or "jackson" has Java library that is able to transform your JSON string to a TreeNode. You can then access various fields.
#Test
public void test() throws IOException {
String AllCustomLockingCriterias = "{\"TemplateArray\":[{\"Id\":16,\"Name\":\"Machine\",\"type\":\"PM\"},\n" +
" {\"Id\":17,\"Name\":\"Ethernet\",\"type\":\"PM\"},\n" +
" {\"Id\":18,\"Name\":\"Hard Disk\",\"type\":\"PM\"}]}";
//create mapper to map JSON string to handy Java object
ObjectMapper objectMapper = new ObjectMapper();
JsonNode rootNode = objectMapper.readValue(AllCustomLockingCriterias,JsonNode.class);
//fetch value that has field name "TemplateArray"
JsonNode templateArray = rootNode.get("TemplateArray");
//loop over the values in the TemplateArray and extract Name, if present.
for(JsonNode subNode : templateArray){
if(subNode.has("Name")){
System.out.println(subNode.get("Name"));
}
}
}
Use JsonNode with JPointer.
Example:
ObjectMapper mapper = new ObjectMapper();
JsonNode node = mapper.readValue(
"{\"TemplateArray\":[{\"Id\":16,\"Name\":\"Machine\",\"type\":\"PM\"}, {\"Id\":17,\"Name\":\"Ethernet\",\"type\":\"PM\"},{\"Id\":18,\"Name\":\"Hard Disk\",\"type\":\"PM\"}]}",
JsonNode.class);
node.at("/TemplateArray").forEach(a -> System.out.println(a.at("/Name")));
Prints:
"Machine"
"Ethernet"
"Hard Disk"
I am getting the String in following format which is causing problem while parsing using Jackson ObjectMapper readTree api. Code used to parse the given String is
ObjectMapper objectMapper = new ObjectMapper();
objectMapper.configure(JsonParser.Feature.ALLOW_SINGLE_QUOTES, true);
objectMapper.configure(JsonParser.Feature.ALLOW_BACKSLASH_ESCAPING_ANY_CHARACTER, true);
objectMapper.configure(JsonParser.Feature.ALLOW_UNQUOTED_FIELD_NAMES, true);
objectMapper.configure(JsonParser.Feature.ALLOW_COMMENTS, true);
objectMapper.configure(JsonParser.Feature.ALLOW_UNQUOTED_CONTROL_CHARS, true);
JsonNode rootNode = objectMapper.readTree(inputString);
It is throwing exception when it encounters "7" in the below String
{
OBJECT_CONVERSION_ERROR:"Failed..."
Portal:{
7061:"User is....."}
}
How to convert such a String in Valid JSON format using JAVA ?
I am using jackson-all-1.9.11.jar
Below is my exception message
org.codehaus.jackson.JsonParseException: Unexpected character ('7' (code 55)): was expecting either valid name character (for unquoted name) or double-quote (for quoted) to start field name
at [Source: java.io.StringReader#3fb1549b; line: 1, column: 1433]
Is there any way to convert the input String in valid json format before passing it to Object Mapper for parsing it ?
The Jackson ObjectMapper expects double-quoted field names in its default configuration.
To change this behavior you could do the following:
ObjectMapper mapper = new ObjectMapper();
mapper.configure(JsonParser.Feature.ALLOW_UNQUOTED_FIELD_NAMES, true);
JSONParser parser = new JSONParser(); JSONObject json = (JSONObject)
parser.parse(stringToParse);
Read more: http://www.java67.com/2016/10/3-ways-to-convert-string-to-json-object-in-java.html#ixzz4y2fACQlg
I use Jackson library to generate json string like this:
ObjectMapper objectMapper = new ObjectMapper();
String str = objectMapper.writeValueAsString(model);
and this snipped code for instance generate somtething like this:
{"x" : "This is x", "y" : "This is y"}
but I want to generate something like this:
{'x' : 'This is x', 'y' : 'This is y'}
I mean how can I change the double quote string with single quote string.I try to change code like this:
ObjectMapper objectMapper = new ObjectMapper();
objectMapper.configure(JsonParser.Feature.ALLOW_SINGLE_QUOTES, true);
String str = objectMapper.writeValueAsString(model);
but this snipped code generate the first one.
and of course I can handle this problem with replace method but I want Jackson library do this for me.
How can I handle this problem?
objectMapper.configure(JsonParser.Feature.ALLOW_SINGLE_QUOTES, true); is about allowing single quotes in deserializing (JSON to Objects), not serializing (Objects to JSON) as you want.
In serializing, the issue seems to be with Jackson 1.X's default serializer. Below is the code that Jackson uses to write the String values. As you can see, the double quotes are hard coded and thus unchangeable through configuration:
#Override
public void writeString(String text)
throws IOException, JsonGenerationException
{
_verifyValueWrite("write text value");
if (text == null) {
_writeNull();
return;
}
if (_outputTail >= _outputEnd) {
_flushBuffer();
}
_outputBuffer[_outputTail++] = '"'; // <----------------- opening quote
_writeString(text); // <----------------- string actual value
// And finally, closing quotes
if (_outputTail >= _outputEnd) {
_flushBuffer();
}
_outputBuffer[_outputTail++] = '"'; // <----------------- closing quote
}
To achieve what you want, there are at least two options:
1: Replace the quotes using Regex:
This is a safe approach because Jackson gives the double quotes (") already escaped (\"). All you have to do is escape the single quotes and switch the " around properties names and values:
ObjectMapper objectMapper = new ObjectMapper();
String str = objectMapper.writeValueAsString(model);
System.out.println("Received.: "+str);
str = str.replaceAll("'", "\\\\'"); // escapes all ' (turns all ' into \')
str = str.replaceAll("(?<!\\\\)\"", "'"); // turns all "bla" into 'bla'
System.out.println("Converted: "+str);
Output:
Received.: {"x":"ab\"c","y":"x\"y'z","z":15,"b":true}
Converted: {'x':'ab\"c','y':'x\"y\'z','z':15,'b':true}
Or 2: User a custom JsonSerializer on every String field
Declare the custom serializer:
public class SingleQuoteStringSerializer extends JsonSerializer<String> {
#Override
public void serialize(String str, JsonGenerator jGen, SerializerProvider sP)
throws IOException, JsonProcessingException {
str = str.replace("'", "\\'"); // turns all ' into \'
jGen.writeRawValue("'" + str + "'"); // write surrounded by single quote
}
}
Use it in the fields you want to single quote:
public class MyModel {
#JsonSerialize(using = SingleQuoteStringSerializer.class)
private String x;
...
And proceed as usual (QUOTE_FIELD_NAMES == false is used to unquote the field names):
ObjectMapper objectMapper = new ObjectMapper();
objectMapper.configure(JsonGenerator.Feature.QUOTE_FIELD_NAMES, false);
String str = objectMapper.writeValueAsString(model);
System.out.println("Received.: "+str);
Output:
Received.: {x:'ab"c',y:'x"y\'z',z:15,b:true}
Note: Since you seem to be wanting to embed the JSON into another, this last approach may also require escaping the "s (see x:'ab"c').
Configure ObjectMapper in the following way:
final ObjectMapper mapper = new ObjectMapper();
mapper.configure(JsonGenerator.Feature.QUOTE_FIELD_NAMES, false);
mapper.configure(JsonParser.Feature.ALLOW_UNQUOTED_FIELD_NAMES, true);
//this may be what you need
mapper.configure(JsonParser.Feature.ALLOW_SINGLE_QUOTES, true);
Try looking into gson. It would look like this in gson.
House myHouse = new House();
Gson gson = new Gson();
String json = gson.toJson(myHouse);
Done...
http://code.google.com/p/google-gson/
As I said in the comment that's not valid JSON and it doesn't make any sense to escape it. You should handle it in a different way.
You should put that object inside a property.
I think you want to have something like
{"myString":"{\"fake json\":\"foo\"}"}
instead you should have:
{"myString":{"fake json":"foo"}}
That should be the proper way to handle this.
I need to convert an object to JsonNode because I need to manipulate the generated Json before returning it.
ObjectMapper mapper = new ObjectMapper();
Float f = 1.4f;
JsonNode node = mapper.convertValue(f, JsonNode.class)
Problem is, that node contains 1.399999976158142 instead of 1.4. Even if I serialize node to JSON...
String output = mapper.writeValueAsString(node);
.. output is 1.399999976158142
If I'm only using writeValueAsString, the result is correct.