jersey使用Gson

jersey restful接口實現請參考博客關於jersey restful接口一文。

使用Gson:

1.須要GsonJsonProvider。

package com.message.ws;

import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.io.UnsupportedEncodingException;
import java.lang.annotation.Annotation;
import java.lang.reflect.Type;

import javax.ws.rs.Consumes;
import javax.ws.rs.Produces;
import javax.ws.rs.WebApplicationException;
import javax.ws.rs.core.MediaType;
import javax.ws.rs.core.MultivaluedMap;
import javax.ws.rs.ext.MessageBodyReader;
import javax.ws.rs.ext.MessageBodyWriter;
import javax.ws.rs.ext.Provider;

import com.google.gson.Gson;
import com.google.gson.GsonBuilder;

@Provider  
@Produces(MediaType.APPLICATION_JSON)  
@Consumes(MediaType.APPLICATION_JSON)  
public class GsonJsonProvider implements MessageBodyWriter<Object>,  
        MessageBodyReader<Object> {  
  
    private static final String UTF_8 = "UTF-8";  
  
    private Gson gson;  
  
    private Gson getGson() {  
        if (gson == null) {  
            final GsonBuilder gsonBuilder = new GsonBuilder();  
            gson = gsonBuilder.create();  
        }  
        return gson;  
    }  
  
    @Override  
    public boolean isReadable(Class<?> type, Type genericType,  
            java.lang.annotation.Annotation[] annotations, MediaType mediaType) {  
        return true;  
    }  
  
    @Override  
    public Object readFrom(Class<Object> type, Type genericType,  
            Annotation[] annotations, MediaType mediaType,  
            MultivaluedMap<String, String> httpHeaders, InputStream entityStream) {  
  
        InputStreamReader streamReader = null;  
        try {  
            streamReader = new InputStreamReader(entityStream, UTF_8);  
        } catch (UnsupportedEncodingException e) {  
            // TODO Auto-generated catch block  
            e.printStackTrace();  
        }  
        try {  
            Type jsonType;  
            if (type.equals(genericType)) {  
                jsonType = type;  
            } else {  
                jsonType = genericType;  
            }  
  
            return getGson().fromJson(streamReader, jsonType);  
        } finally {  
            try {  
                streamReader.close();  
            } catch (IOException e) {  
                // TODO Auto-generated catch block  
                e.printStackTrace();  
            }  
        }  
    }  
  
    @Override  
    public boolean isWriteable(Class<?> type, Type genericType,  
            Annotation[] annotations, MediaType mediaType) {  
        return true;  
    }  
  
    @Override  
    public long getSize(Object object, Class<?> type, Type genericType,  
            Annotation[] annotations, MediaType mediaType) {  
        return -1;  
    }  
  
    @Override  
    public void writeTo(Object object, Class<?> type, Type genericType,  
            Annotation[] annotations, MediaType mediaType,  
            MultivaluedMap<String, Object> httpHeaders,  
            OutputStream entityStream) throws IOException,  
            WebApplicationException {  
        OutputStreamWriter writer = new OutputStreamWriter(entityStream, UTF_8);  
        try {  
            Type jsonType;  
            if (type.equals(genericType)) {  
                jsonType = type;  
            } else {  
                jsonType = genericType;  
            }  
            getGson().toJson(object, jsonType, writer);  
        } finally {  
            writer.close();  
        }  
    }  
}

2.將provider注入spring容器中

<bean id="gsonProvider" class="com.message.ws.GsonJsonProvider" scope="singleton"/>