Package org.springframework.http.converter.json

Class GsonHttpMessageConverter

java.lang.Object

org.springframework.http.converter.AbstractHttpMessageConverter<T>

org.springframework.http.converter.AbstractGenericHttpMessageConverter<Object>

org.springframework.http.converter.json.AbstractJsonHttpMessageConverter

org.springframework.http.converter.json.GsonHttpMessageConverter

All Implemented Interfaces:

GenericHttpMessageConverter<Object>, HttpMessageConverter<Object>

public class GsonHttpMessageConverter
extends AbstractJsonHttpMessageConverter

Implementation of HttpMessageConverter that can read and write JSON using the Google Gson library.

This converter can be used to bind to typed beans or untyped HashMaps. By default, it supports application/json and application/*+json with UTF-8 character set.

Tested against Gson 2.8; compatible with Gson 2.0 and higher.

Since:

4.1

Author:

Roy Clarkson, Juergen Hoeller

See Also:

• Gson
• GsonBuilder
• setGson(com.google.gson.Gson)

Field Summary

Fields inherited from class org.springframework.http.converter.json.AbstractJsonHttpMessageConverter

DEFAULT_CHARSET

Fields inherited from class org.springframework.http.converter.AbstractHttpMessageConverter

logger

Constructor Summary

Constructors

Constructor	Description
GsonHttpMessageConverter()	Construct a new GsonHttpMessageConverter with default configuration.
GsonHttpMessageConverter(com.google.gson.Gson gson)	Construct a new GsonHttpMessageConverter with the given delegate.

Method Summary

Modifier and Type	Method	Description
com.google.gson.Gson	getGson()	Return the configured Gson instance for this converter.
protected Object	readInternal(Type resolvedType, Reader reader)	Template method that reads the JSON-bound object from the given Reader.
void	setGson(com.google.gson.Gson gson)	Set the Gson instance to use.
protected boolean	supportsRepeatableWrites(Object o)	Indicates whether this message converter can write the given object multiple times.
protected void	writeInternal(Object object, Type type, Writer writer)	Template method that writes the JSON-bound object to the given Writer.

Methods inherited from class org.springframework.http.converter.json.AbstractJsonHttpMessageConverter

read, readInternal, setJsonPrefix, setPrefixJson, writeInternal

Methods inherited from class org.springframework.http.converter.AbstractGenericHttpMessageConverter

canRead, canWrite, supports, write, writeInternal

Methods inherited from class org.springframework.http.converter.AbstractHttpMessageConverter

addDefaultHeaders, canRead, canRead, canWrite, canWrite, getContentLength, getDefaultCharset, getDefaultContentType, getSupportedMediaTypes, read, setDefaultCharset, setSupportedMediaTypes, write

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.springframework.http.converter.HttpMessageConverter

canRead, canWrite, getSupportedMediaTypes, getSupportedMediaTypes, read, write

Constructor Details

GsonHttpMessageConverter

public GsonHttpMessageConverter()

Construct a new GsonHttpMessageConverter with default configuration.

GsonHttpMessageConverter

public GsonHttpMessageConverter(com.google.gson.Gson gson)

Construct a new GsonHttpMessageConverter with the given delegate.

Parameters:

gson - the Gson instance to use

Since:

5.0

Method Details

setGson

public void setGson(com.google.gson.Gson gson)

Set the Gson instance to use. If not set, a default Gson instance will be used.

Setting a custom-configured Gson is one way to take further control of the JSON serialization process.

See Also:

• GsonHttpMessageConverter(Gson)

getGson

public com.google.gson.Gson getGson()

Return the configured Gson instance for this converter.

readInternal

protected Object readInternal(Type resolvedType,
 Reader reader)
                       throws Exception

Description copied from class: AbstractJsonHttpMessageConverter

Template method that reads the JSON-bound object from the given Reader.

Specified by:

readInternal in class AbstractJsonHttpMessageConverter

Parameters:

resolvedType - the resolved generic type

reader - the Reader to use

Returns:

the JSON-bound object

Throws:

Exception - in case of read/parse failures

writeInternal

protected void writeInternal(Object object,
 @Nullable
 Type type,
 Writer writer)
                      throws Exception

Description copied from class: AbstractJsonHttpMessageConverter

Template method that writes the JSON-bound object to the given Writer.

Specified by:

writeInternal in class AbstractJsonHttpMessageConverter

Parameters:

object - the object to write to the output message

type - the type of object to write (may be null)

writer - the Writer to use

Throws:

Exception - in case of write failures

supportsRepeatableWrites

protected boolean supportsRepeatableWrites(Object o)

Description copied from class: AbstractHttpMessageConverter

Indicates whether this message converter can write the given object multiple times.

The default implementation returns false.

Overrides:

supportsRepeatableWrites in class AbstractHttpMessageConverter<Object>

Parameters:

o - the object t

Returns:

true if t can be written repeatedly; false otherwise