Jackson Full Data Binding: Difference between revisions

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=Java to JSON=
=Java to JSON=
<tt>ObjectMapper</tt> will introspect a Java object coded according to the Java Beans conventions and output it as JSON content.
The method names (without the "get") will be used as field names.
Example:
<pre>
import com.fasterxml.jackson.databind.ObjectMapper;
ByteArrayOutputStream baos = new ByteArrayOutputStream();
ObjectMapper om = new ObjectMapper();
Object root = ... // some hierarchical object
om.writeValue(baos, root);
System.out.println(new String(baos.toByteArray()));
</pre>


==Java to JSON Code Example==
==Java to JSON Code Example==

Revision as of 20:46, 26 February 2017

Internal

Overview

JSON to Java

import com.fasterxml.jackson.databind.ObjectMapper;

ObjectMapper om = new ObjectMapper();
Token token = on.readValue(inputStream, Token.class);

This is a generic conversion method, assuming that the JSON content matches the internal structure of the type <T>:

public static <T> T fromJson(String json, Class<? extends T> c) throws JsonConversionException {

    try {
        ObjectMapper objectMapper = new ObjectMapper();
        return objectMapper.readValue(new ByteArrayInputStream(json.getBytes()), c);
    }
    catch (Exception e) {
       throw new JsonConversionException(e);
    }
}


To enable generic type information (like "Map<String,Object>"), you have to use TypeReference container as explained above.

JSON to Java Code Example


Java to JSON

ObjectMapper will introspect a Java object coded according to the Java Beans conventions and output it as JSON content.

The method names (without the "get") will be used as field names.

Example:

import com.fasterxml.jackson.databind.ObjectMapper;

ByteArrayOutputStream baos = new ByteArrayOutputStream();
ObjectMapper om = new ObjectMapper();
Object root = ... // some hierarchical object
om.writeValue(baos, root);
System.out.println(new String(baos.toByteArray()));


Java to JSON Code Example