Package aQute.lib.json

Class JSONCodec

java.lang.Object

aQute.lib.json.JSONCodec

public class JSONCodec
extends Object

This is a simple JSON Coder and Encoder that uses the Java type system to convert data objects to JSON and JSON to (type safe) Java objects. The conversion is very much driven by classes and their public fields. Generic information, when present is taken into account.

Usage patterns to encode:

  JSONCoder codec = new JSONCodec(); // assert "1".equals(
 codec.enc().to().put(1).toString()); assert "[1,2,3]".equals(
 codec.enc().to().put(Arrays.asList(1,2,3).toString()); Map m = new HashMap();
 m.put("a", "A"); assert "{\"a\":\"A\"}".equals(
 codec.enc().to().put(m).toString()); static class D { public int a; } D d =
 new D(); d.a = 41; assert "{\"a\":41}".equals(
 codec.enc().to().put(d).toString());
 

It is possible to redirect the encoder to another output (default is a string). See Encoder.to(),Encoder.to(File), Encoder.to(OutputStream), Encoder.to(Appendable). To reset the string output call Encoder.to().

This Codec class can be used in a concurrent environment. The Decoders and Encoders, however, must only be used in a single thread.

Will now use hex for encoding byte arrays

Field Summary

Fields

Modifier and Type	Field	Description
private static BooleanHandler	bh
private static ByteArrayHandler	byteh
private static CharacterHandler	ch
private static CollectionHandler	dch
private static FileHandler	fh
private static final WeakHashMap<Type,Handler>	handlers
(package private) boolean	ignorenull
(package private) Map<Type,Handler>	localHandlers
private static DateHandler	sdh
private static StringHandler	sh
private static SpecialHandler	sph
(package private) static final String	START_CHARACTERS
private static UUIDHandler	uuidh

Constructor Summary

Constructors

Constructor	Description
JSONCodec()

Method Summary

Modifier and Type	Method	Description
JSONCodec	addHandler(Type type, Handler handler)	Add a new local handler
Decoder	dec()	Create a new Decoder with the state and appropriate API.
(package private) Object	decode(Type type, Decoder isr)
Encoder	enc()	Create a new Encoder with the state and appropriate API.
(package private) void	encode(Encoder app, Object object, Type type, Map<Object,Type> visited)
(package private) Handler	getHandler(Type type, Class<?> actual)	This method figures out which handler should handle the type specific stuff.
(package private) Class<?>	getRawClass(Type type)
private int	hexDigit(int c)
boolean	isIgnorenull()
(package private) void	parseArray(Collection<Object> list, Type componentType, Decoder r)
private Number	parseNumber(Decoder r)
(package private) String	parseString(Decoder r)
JSONCodec	setIgnorenull(boolean ignorenull)	Ignore null values in output and input

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

START_CHARACTERS

static final String START_CHARACTERS

See Also:

• Constant Field Values

handlers

private static final WeakHashMap<Type,Handler> handlers

sh

private static StringHandler sh

bh

private static BooleanHandler bh

ch

private static CharacterHandler ch

dch

private static CollectionHandler dch

sph

private static SpecialHandler sph

sdh

private static DateHandler sdh

fh

private static FileHandler fh

byteh

private static ByteArrayHandler byteh

uuidh

private static UUIDHandler uuidh

ignorenull

boolean ignorenull

localHandlers

Map<Type,Handler> localHandlers

Constructor Details

JSONCodec

public JSONCodec()

Method Details

enc

public Encoder enc()

Create a new Encoder with the state and appropriate API.

Returns:

an Encoder

dec

public Decoder dec()

Create a new Decoder with the state and appropriate API.

Returns:

a Decoder

encode

void encode(Encoder app,
 Object object,
 Type type,
 Map<Object,Type> visited)
     throws Exception

Throws:

Exception

getHandler

Handler getHandler(Type type,
 Class<?> actual)
            throws Exception

This method figures out which handler should handle the type specific stuff. It returns a handler for each type. If no appropriate handler exists, it will create one for the given type. There are actually quite a lot of handlers since Java is not very object oriented.

Parameters:

type -

Returns:

a Handler appropriate for type

Throws:

Exception

decode

Object decode(Type type,
 Decoder isr)
       throws Exception

Throws:

Exception

parseString

String parseString(Decoder r)
            throws Exception

Throws:

Exception

hexDigit

private int hexDigit(int c)
              throws EOFException

Throws:

EOFException

parseNumber

private Number parseNumber(Decoder r)
                    throws Exception

Throws:

Exception

parseArray

void parseArray(Collection<Object> list,
 Type componentType,
 Decoder r)
         throws Exception

Throws:

Exception

getRawClass

Class<?> getRawClass(Type type)

setIgnorenull

public JSONCodec setIgnorenull(boolean ignorenull)

Ignore null values in output and input

Parameters:

ignorenull -

Returns:

this

isIgnorenull

public boolean isIgnorenull()

addHandler

public JSONCodec addHandler(Type type,
 Handler handler)

Add a new local handler