These methods are in `ObjectNode`: the division is such that most read operations are included in `JsonNode`, but mutations in `ObjectNode` and `ArrayNode`.

Note that you can just change first line to be:

    ObjectNode jNode = mapper.createObjectNode();
    // version ObjectMapper has should return ObjectNode type

or

    ObjectNode jNode = (ObjectNode) objectCodec.createObjectNode();
    // ObjectCodec is in core part, must be of type JsonNode so need cast


I&#39;ve recently found even more interesting way to create any `ValueNode` or `ContainerNode` (Jackson v2.3).

    ObjectNode node = JsonNodeFactory.instance.objectNode();


I&#39;m having a hard time getting the height of lower screen resolution because my screen resolution is 1920x1080.

Does anyone know how to get height and width of the screen resolution?

I checked my work on a 1024x768 resolution and it is rendered all messed up.

CSS get height of screen resolution

I&#39;ve been trying to implement an application that requires camera preview on a surface.
As I see the things, both activity and surface lifecycles consist of the following states:

1. When I first launch my Activity: `onResume()-&gt;onSurfaceCreated()-&gt;onSurfaceChanged()`
2. When I leave my Activity: `onPause()-&gt;onSurfaceDestroyed()`

In this scheme, I can do corresponding calls like open/release camera and start/stop preview in `onPause/onResume` and `onSurfaceCreated()/onSurfaceDestroyed()`.

It works fine, unless I lock the screen. When I launch the app, then lock the screen and unlock it later I see:

`onPause()` - and nothing else after the screen is locked - then `onResume()` after unlock - and no surface callbacks after then. Actually, `onResume()` is called after the power button is pressed and the screen is on, but the lock screen is still active, so, it&#39;s before the activity becomes even visible.

With this scheme, I get a black screen after unlock, and no surface callbacks are called.

Here&#39;s a code fragment that doesn&#39;t involve actual work with the camera, but the `SurfaceHolder` callbacks. The issue above is reproduced even with this code on my phone (callbacks are called in a normal sequence when you press &quot;Back&quot; button, but are missing when you lock the screen):

    class Preview extends SurfaceView implements SurfaceHolder.Callback {
    
    	private static final String tag= &quot;Preview&quot;;
    
    	public Preview(Context context) {
    		super(context);
    		Log.d(tag, &quot;Preview()&quot;);
    		SurfaceHolder holder = getHolder();
    		holder.addCallback(this);
    		holder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
    	}
    
    	public void surfaceCreated(SurfaceHolder holder) {
    		Log.d(tag, &quot;surfaceCreated&quot;);
    	}
    
    	public void surfaceDestroyed(SurfaceHolder holder) {
    		Log.d(tag, &quot;surfaceDestroyed&quot;);
    	}
    
    	public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) {
    		Log.d(tag, &quot;surfaceChanged&quot;);
    	}
    }

Any ideas on why the surface remains undestroyed after the Activity is paused? Also, how do you handle camera lifecycle in such cases?

How SurfaceHolder callbacks are related to Activity lifecycle?

I have a new JsonNode that I created

    JsonNode jNode = new ObjectCodec().createObjectNode();

with this node, how do I then add key value pairs within so that I can construct this new node with the new values? What I read in http://www.cowtowncoder.com/blog/archives/2011/08/entry_460.html mentioned about using

    jNode.with(&quot;newNode&quot;).put(&quot;key1&quot;,&quot;value1&quot;);

But looking at the APIs for Jackson&#39;s JsonNode (v1.8) does not show any method as such.

how to create insert new nodes in JsonNode?

I have a new JsonNode that I created
<pre><code class="hljs language-ini">JsonNode jNode = new ObjectCodec().createObjectNode();
</code></pre>
with this node, how do I then add key value pairs within so that I can construct this new node with the new values? What I read in <a href="http://www.cowtowncoder.com/blog/archives/2011/08/entry_460.html" target="_blank" rel="noopener noreferrer">http://www.cowtowncoder.com/blog/archives/2011/08/entry_460.html</a> mentioned about using
<pre><code class="hljs language-csharp">jNode.with("newNode").put("key1","value1");
</code></pre>
But looking at the APIs for Jackson's JsonNode (v1.8) does not show any method as such.

I have inherited a certain bit code that has the @JsonProperty annotation on getter/setters. The purpose is so that when the object is serialized using the Jackson library, the fields have that specific name.

Current code:

    private String fileName;
    
    @JsonProperty(&quot;FILENAME&quot;)
    public String getFileName()
    {
        return fileName;
    }

    @JsonProperty(&quot;FILENAME&quot;)
    public void setFileName(String fileName)
    {
    	this.fileName = fileName;
    }



Now for another tool, I need to annotate the field with JsonProperty as well. So this will be my changed code:

    @JsonProperty(&quot;FILENAME&quot;)
    private String fileName;
    
    @JsonProperty(&quot;FILENAME&quot;)
    public String getFileName()
    {
        return fileName;
    }

    @JsonProperty(&quot;FILENAME&quot;)
    public void setFileName(String fileName)
    {
    	this.fileName = fileName;
    }


Has anyone used this same annotation on both - the field as well as the getter/setters? I looked around on the net but didn&#39;t see anything.

I have compiled &amp; run the code but I&#39;m not sure if this would this cause any problems down the road. Any thoughts on this?

@JsonProperty annotation on field as well as getter/setter

I have a big object I want to convert to JSON and send. However it has circular structure. I want to toss whatever circular references exist and send whatever can be stringified. How do I do that?

Thanks.

    var obj = {
      a: &quot;foo&quot;,
      b: obj
    }


I want to stringify obj into:

    {&quot;a&quot;:&quot;foo&quot;}

How can I print a circular structure in a JSON-like format?

I have a json string, which I should deSerialize to the following class

    class Data &lt;T&gt; {
        int found;
        Class&lt;T&gt; hits
    }

How do I do it?
This is the usual way

    mapper.readValue(jsonString, Data.class);
But how do I mention what T stands for?


Jackson - Deserialize using generic class

I wish to use the `&quot;encoding/json&quot;` package to marshal a struct declared in one of the imported packages of my application.

Eg.:

    type T struct {
        Foo int
    }

Because it is imported, all available (exported) fields in the struct begins with an upper case letter. But I wish to have lower case key names:

    out, err := json.Marshal(&amp;T{Foo: 42})

will result in

&gt; {&quot;Foo&quot;:42}

but I wish to get

&gt; {&quot;foo&quot;:42}

Is it possible to get around the problem in some easy way?

Lowercase JSON key names with JSON Marshal in Go

I am using `jQuery` to edit my form which is built in `Symfony`.

I am showing the form in `jQuery` dialog and then submitting it.

Data is entering correctly in database.

But I don&#39;t know whether I need to send some `JSON` back to `jQuery`. Actually I am bit confused with `JSON` thing.

Suppose I have added a row in my table with ``jQuery and when I submit the form then after data is submitted I want to send back those row data so that I can dynamically add the table row to show the data added.

I am confused how can get that data back.

This is my current code:

    $editForm = $this-&gt;createForm(new StepsType(), $entity);
    
    $request = $this-&gt;getRequest();
    
    $editForm-&gt;bindRequest($request);
    
    if ($editForm-&gt;isValid()) {
        $em-&gt;persist($entity);
        $em-&gt;flush();
    
        return $this-&gt;render(&#39;::success.html.twig&#39;);               
    }

This is just the template with success message.

How can I send JSON response in symfony2 controller

    {
      vendors: [
        {
          vendor: {
            id: 367,
            name: &quot;Kuhn-Pollich&quot;,
            company_id: 1,
          }
        },
        {
          vendor: {
            id: 374,
            name: &quot;Sawayn-Hermann&quot;,
            company_id: 1,
          }
      }]
    }

I have a Vendor object that can properly be deserialized from a single &quot;vendor&quot; json, but I want to deserialize this into  a `Vendor[]`, I just can&#39;t figure out how to make Jackson cooperate.  Any tips?


Jackson - How to process (deserialize) nested JSON?

How can Jackson be configured to ignore a field value during serialization if that field&#39;s value is null. 

For example:

    public class SomeClass {
       // what jackson annotation causes jackson to skip over this value if it is null but will 
       // serialize it otherwise 
       private String someValue; 
    }

How to tell Jackson to ignore a field during serialization if its value is null?

I would like to know if `@JsonTypeInfo` annotation can be used for interfaces. I have set of classes which should be serialized and deserialized.

Here is what I&#39;m trying to do. I have two implementation classes `Sub1`, `Sub2` implementing `MyInt`. Some of the model classes have the interface reference for the implementation types. I would like to deserialize the objects based on polymorphism

    @JsonTypeInfo(use=JsonTypeInfo.Id.NAME, include=As.WRAPPER_OBJECT)
    @JsonSubTypes({
        @Type(name=&quot;sub1&quot;, value=Sub1.class), 
        @Type(name=&quot;sub2&quot;, value=Sub2.class)})
    public interface MyInt{
    }

    @JsonTypeName(&quot;sub1&quot;)
    public Sub1 implements MyInt{
    }
    
    @JsonTypeName(&quot;sub2&quot;)
    public Sub2 implements MyInt{
    }

I get the following `JsonMappingException`:

&gt; Unexpected token (END_OBJECT), expected FIELD_NAME: need JSON String
&gt; that contains type id



Content Type	Original Author	Original Content on Stackoverflow
Question	Dexter Cato	View Question on Stackoverflow
Solution 1 - Json	StaxMan	View Answer on Stackoverflow
Solution 2 - Json	rand0m86	View Answer on Stackoverflow

how to create insert new nodes in JsonNode?

Json Problem Overview

Json Solutions

Solution 1 - Json

Solution 2 - Json

How SurfaceHolder callbacks are related to Activity lifecycle?

CSS get height of screen resolution

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