Svenson offers you the possibility to generate JSON datasets from your java classes being a nested graph of:
- POJOs
- Java Beans
- Arrays
- Collections
- Maps
In the most simple case you can just do a
import org.svenson.JSON;
...
String json = JSON.defaultJSON().forValue( yourObjects );
you can also generate JSON while ignoring certain properties:
import org.svenson.JSON;
...
String json = JSON.defaultJSON().forValue( yourObjects, Arrays.asList("foo","bar"));
This would generate JSON for "yourObjects" while ignoring all properties named "foo" and "bar" in all beans.
The org.svenson.JSONProperty annotation allows you to define another JSON property name for your properties, make JSON ignore your properties completely or ignore them if they are null.
import org.svenson.JSON;
import org.svenson.JSONProperty;
public class MyBean
{
private String foo,bar,baz;
@JSONProperty("notFoo")
public String getFoo()
{
return foo;
}
@JSONProperty(ignoreIfNull = true)
public String getBar()
{
return foo;
}
@JSONProperty(ignore = true)
public String getBaz()
{
return foo;
}
}
Here the foo property would be generated as "notFoo" property in JSON, the "bar" property would be ignored if it is null, and the "baz" property would be ignored completely.
If your classes implement the org.svenson.JSONable, they can provide their own JSON representation.
import org.svenson.JSON;
import org.svenson.JSONable;
public class MyClass implements JSONable
{
private String member;
...
public String toJSON()
{
return JSON.defaultJSON().quote(this.member);
}
}
Here MyClass would just generate one of its members as JSON string. As you can see, you can use the JSON class to help you implementing toJSON().
A JSONifier is a class that can convert another class into JSON. It needs to implement org.svenson.JSONifier.
import org.svenson.JSON;
import org.svenson.JSONifier;
public class MyJSONifier implements JSONifier
{
public String toJSON(Object o)
{
MyClass myClass = (MyClass)o;
return JSON.defaultJSON().quote(myClass.getMember());
}
}
This would be a simple JSONifier that turns instances of MyClass into JSON by replacing them with one of its members. To use this JSONifier you have to register it in your own JSON instance.
import org.svenson.JSON;
...
// assume myClassInstance is an instance of MyClass
JSON json = new JSON();
json.registerJSONifier(MyClass.class, new MyJSONifier());
String output = json.forValue( myClassInstance);