JSONMapper (JSON Tools 2.0 API)

java.lang.Object
- com.sdicons.json.mapper.JSONMapper

```
public class JSONMapper
extends Object
```
The mapper class is able to convert a JSON representation to/from a Java representation. The mapper's goal is to produce a nice and clean JSON output which can easily be used in e.g. Javascript context. As a consequence, not all Java constructs are preserved during the conversion to/from JSON. The mapper is the best choice in an application where the clean JSON format is central. If the emphasis is on exact Java serialization where types are preserved, take a look at the serializer tool. The main difference between the serializer and the mapper is that the serializer keeps as much type information and structure information in the JSON data where the mapper uses the type information in the provided Java classes to interpret the JSON data.
Example: The Java model
```
 
 public class Person {
   private String name;
   private String phoneNumber;
   private int age;
   // Getters and setters omitted.
   // ...
 }
 
 
```
The mapping code
```
 
 // Create a person.
 Person p = new Person();
 p.setName("Mr. Jason Tools");
 p.setPhoneNumber("0123456789");
 p.setAge(40);
 // Map and print.
 JSONMapper mapper = new JSONMapper();
 JSONValue json = mapper.toJSON(p);
 System.out.println(json.render(true));
 
 
```
The resulting JSON text
```
 
 {
    "age" : 40,
    "name" : "Mr. Jason Tools",
    "phoneNumber" : "0123456789"
 }
 
 
```
See Also:
JSONSerializer

Field Summary

Fields
Modifier and Type	Field and Description
`static String`	`DATEFORMAT_DEFAULT` The default pattern used by the DateMapper to convert String representations into Java dates.
`static String`	`OBJMAPPING_FIELD` The object mapper will use field access to access the contents of an instance.
`static String`	`OBJMAPPING_PROPERTY` The object mapper will use JavaBean getters and setters to access the contents of an instance.
`static String`	`OPT_DATEFORMAT` The mapping option DATAFORMAT indicates which date pattern will be used by the DateMapper to convert String values to Dates and vice versa.
`static String`	`OPT_OBJMAPPING` The mapping option OBJMAPPING indicates whether property mapping of field mapping will be used.

Constructor Summary

Constructors
Constructor and Description

JSONMapper()

JSONMapper(ClassMapper... helpers)

Constructors
Constructor and Description
`JSONMapper()`
`JSONMapper(ClassMapper... helpers)`

Method Summary

Methods
Modifier and Type	Method and Description
`void`	`addHelper(ClassMapper helper)` Add custom helper class.
`Object`	`getMappingOption(String key, Object defaultValue)` Get the value of a mapping option.
`boolean`	`hasMappingOption(String key)` Check to see if an option was set explicitly or not.
`void`	`setMappingOption(String key, Object value)` Add a mapping option.
`Object`	`toJava(JSONValue json)` Map a JSON representation to a Java object.
`Object`	`toJava(JSONValue aValue, Class<?> aPojoClass)` Map a JSON representation to a Java object.
`Object`	`toJava(JSONValue json, ParameterizedType genericType)` Map a JSON representation to a Java object.
`JSONValue`	`toJSON(Object pojo)` Map a POJO to the JSON representation.
`void`	`useJavaBeanAccess()` The objects that fall back on the general object mapper will be mapped by using their JavaBean properties.
`void`	`usePojoAccess()` The objects that fall back on the general object mapper will be mapped by using their fields directly.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - OPT_OBJMAPPING
```
public static final String OPT_OBJMAPPING
```
    The mapping option OBJMAPPING indicates whether property mapping of field mapping will be used. There are two possible values OBJMAPPING_FIELD or OBJMAPPING_PROPERTY.
    
    See Also:
    setMappingOption(String, Object), Constant Field Values
  - OBJMAPPING_FIELD
```
public static final String OBJMAPPING_FIELD
```
    The object mapper will use field access to access the contents of an instance.
    
    See Also:
    OPT_OBJMAPPING, Constant Field Values
  - OBJMAPPING_PROPERTY
```
public static final String OBJMAPPING_PROPERTY
```
    The object mapper will use JavaBean getters and setters to access the contents of an instance.
    
    See Also:
    OPT_OBJMAPPING, Constant Field Values
  - OPT_DATEFORMAT
```
public static final String OPT_DATEFORMAT
```
    The mapping option DATAFORMAT indicates which date pattern will be used by the DateMapper to convert String values to Dates and vice versa.
    
    See Also:
    DATEFORMAT_DEFAULT, Constant Field Values
  - DATEFORMAT_DEFAULT
```
public static final String DATEFORMAT_DEFAULT
```
    The default pattern used by the DateMapper to convert String representations into Java dates. You can modify the pattern using the OPT_DATEFORMAT mapper option.
    
    See Also:
    OPT_DATEFORMAT, setMappingOption(String, Object), Constant Field Values
- Constructor Detail
  - JSONMapper
```
public JSONMapper(ClassMapper... helpers)
```
  - JSONMapper
```
public JSONMapper()
```
- Method Detail
  - toJava
```
public Object toJava(JSONValue aValue,
            Class<?> aPojoClass)
              throws MapperException
```
    Map a JSON representation to a Java object.
    
    Parameters:
    aValue - The JSON value that has to be mapped.
    aPojoClass - The class to which the JSON object should be mapped.
    
    Returns:
    The resulting Java object, the POJO representation.
    
    Throws:
    
    MapperException - when an error occurs during mapping.
  - toJava
```
public Object toJava(JSONValue json,
            ParameterizedType genericType)
              throws MapperException
```
    Map a JSON representation to a Java object.
    
    Parameters:
    json - The JSON value that has to be mapped.
    genericType - A type indication to help the mapper map the JSON text.
    
    Returns:
    The resulting Java POJO.
    
    Throws:
    
    MapperException - When the JSON text cannot be mapped to POJO.
  - toJava
```
public Object toJava(JSONValue json)
              throws MapperException
```
    Map a JSON representation to a Java object. Since no class nor type hint is passed to the mapper, this method can only handle the most basic mappings.
    
    Parameters:
    json - The JSON value that has to be mapped.
    
    Returns:
    he resulting Java POJO.
    
    Throws:
    
    MapperException - When the JSON text cannot be mapped to POJO.
  - toJSON
```
public JSONValue toJSON(Object pojo)
                 throws MapperException
```
    Map a POJO to the JSON representation.
    
    Parameters:
    pojo - to be mapped to JSON.
    
    Returns:
    The JSON representation.
    
    Throws:
    
    MapperException - If something goes wrong during mapping.
  - addHelper
```
public void addHelper(ClassMapper helper)
```
    Add custom helper class.
    
    Parameters:
    helper - the custom helper you want to add to the mapper.
  - usePojoAccess
```
public void usePojoAccess()
```
    The objects that fall back on the general object mapper will be mapped by using their fields directly. Without further annotations, the default constructor without arguments will be used in the POJO. If this is not sufficient, the @JSONConstructor and @JSONConstructorArgs annotations can be used as well in the mapped POJO to indicate which constructor has to be used.
  - useJavaBeanAccess
```
public void useJavaBeanAccess()
```
    The objects that fall back on the general object mapper will be mapped by using their JavaBean properties. The mapped JavaBean always needs a default constructor without arguments.
  - setMappingOption
```
public void setMappingOption(String key,
                    Object value)
```
    Add a mapping option. The mapping options are passed to all the class mappers, this is the way to configure the class mappers. It can influence the mapping behavior.
    
    Parameters:
    key - The name of the option.
    value - The value of the option.
    See Also:
    OPT_DATEFORMAT, OPT_OBJMAPPING
  - getMappingOption
```
public Object getMappingOption(String key,
                      Object defaultValue)
```
    Get the value of a mapping option. If you write your own parameterized mapper you can use this method to fetch the parameters.
    
    Parameters:
    key - The option name.
    defaultValue - The default value that will be returned if the option is not set.
    
    Returns:
    The value of the option or the default value if the option was not set explicitly.
    See Also:
    OPT_DATEFORMAT, OPT_OBJMAPPING
  - hasMappingOption
```
public boolean hasMappingOption(String key)
```
    Check to see if an option was set explicitly or not. If you write your own parameterized mapper, it can check its options using this method.
    
    Parameters:
    key - The option name.
    
    Returns:
    A boolean indicating whether the option was explicitly set or not.

Class JSONMapper

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

OPT_OBJMAPPING

OBJMAPPING_FIELD

OBJMAPPING_PROPERTY

OPT_DATEFORMAT

DATEFORMAT_DEFAULT

Constructor Detail

JSONMapper

JSONMapper

Method Detail

toJava

toJava

toJava

toJSON

addHelper

usePojoAccess

useJavaBeanAccess

setMappingOption

getMappingOption

hasMappingOption