I am following a tutorial and also used the Stackoverflow question here.
Here is my Java class:
package com.crunchify.tutorial;
import javax.ws.rs.DefaultValue;
import javax.ws.rs.GET;
import javax.ws.rs.Path;
import javax.ws.rs.Consumes;
import javax.ws.rs.QueryParam;
import javax.ws.rs.core.Context;
import javax.ws.rs.core.MediaType;
import javax.ws.rs.core.MultivaluedMap;
import javax.ws.rs.core.UriInfo;
import org.json.simple.JSONObject;
#Path("api")
public class CrunchifyAPI {
#SuppressWarnings("unchecked")
#GET
#Path("/get")
#Consumes(MediaType.TEXT_PLAIN)
public String get(
#DefaultValue("111") #QueryParam("user") int user,
#Context UriInfo uriInfo
) {
MultivaluedMap<String, String> queryParams = uriInfo.getQueryParameters();
String nameParam = queryParams.getFirst("user");
System.out.println("Data Received: " + uriInfo.getRequestUri().getQuery()
+ " | " + nameParam);
JSONObject obj = new JSONObject();
obj.put("auth", true);
String ret = JSONObject.toJSONString(obj);
return ret;
}
}
Following is what I am GET'ing from postman:
GET>> localhost/api/get?user=123
Response is:
{"auth":true}
Server console:
Starting Crunchify's Embedded Jersey HTTPServer...
Started Crunchify's Embedded Jersey HTTPServer Successfully !!!
Data Received: ?user=123 | null
User Authenticated: true
I have tried with passing String, Integer etc but nothing works. The uri Info is getting printed correctly and the response back is also fine. The issue is that I am not getting the parameter to be read in Java Code. I will need to pass many other parameters once I am able to get this going. Please suggest. Thanks!!
I think you're trying too hard. As far as I can tell, doing the following should get you what you want if you call localhost/api/get?user=123:
package com.crunchify.tutorial;
import javax.ws.rs.DefaultValue;
import javax.ws.rs.GET;
import javax.ws.rs.Path;
import javax.ws.rs.Consumes;
import javax.ws.rs.QueryParam;
import javax.ws.rs.core.Context;
import javax.ws.rs.core.MediaType;
import javax.ws.rs.core.MultivaluedMap;
import javax.ws.rs.core.UriInfo;
import org.json.simple.JSONObject;
#Path("api")
public class CrunchifyAPI {
#SuppressWarnings("unchecked")
#GET
#Path("/get")
#Consumes(MediaType.TEXT_PLAIN)
public String get(
#DefaultValue("111") #QueryParam("user") Integer user,
#Context UriInfo uriInfo
) {
System.out.println("Data Received: " + uriInfo.getRequestUri().getQuery()
+ " | " + name);
JSONObject obj = new JSONObject();
obj.put("auth", true);
String ret = JSONObject.toJSONString(obj);
return ret;
}
}
All that extra stuff with the query string isn't needed if all you need is the information passed in the user parameter.
#QueryParam("user") int user
the value of that user int should be 123
See https://www.mkyong.com/webservices/jax-rs/jax-rs-queryparam-example/
Well, I think you're having a problem with Java Types.
If your user is an Integer you should pass it to String first if you want to work with a String (Integer.toString() or String.valueof()).
But the way you're passing the parameter is bothering me, I'm not sure if you can pass integers by text plain medi types.
I am working on restful api of spring and i am send parameters from my browser to my server(localhost). My server will call the link in world wide web and get the result. Here I am getting the exception.
Following is the original link i have to get the
https://eutils.ncbi.nlm.nih.gov/entrez/eutils/esearch.fcgi?db=pubmed&term=science%5bjournal%5d+AND+breast+cancer+AND+2008%5bpdat%5d
THIS IS MY link i call in browser
http://localhost:8080/search?db=pubmed&term=science[journal]+AND+breast+cancer+AND+2008[pdat]
Please help me out.
package com.ncbi.team.utils;
import java.io.UnsupportedEncodingException;
import java.net.URLEncoder;
import java.util.List;
import org.springframework.stereotype.Service;
enter code here
import com.sun.jersey.api.client.Client;
import com.sun.jersey.api.client.ClientResponse;
import com.sun.jersey.api.client.WebResource;
#Service
public class SearchReq {
public String browseURL(List <String> param )
throwsUnsupportedEncodingExce
ption{
StringBuffer sb = new StringBuffer();
String masterURL = "https://eutils.ncbi.nlm.nih.gov/entrez/eutils/esearch.fcgi";
System.out.println(param);
sb.append(masterURL);
for(int i=0;i<param.size();i++)
{
if(i==0){
sb.append("?");
sb.append(param.get(0));
}
else{
sb.append("&"+param.get(i));
}
}
System.out.println("URL Is :"+sb.toString());
Client c = Client.create();
String url=URLEncoder.encode(sb.toString(),"UTF-8");
// WebResource resource = c.resource(URLEncoder.encode(sb.toString(),"UTF-8"));
WebResource resource = c.resource(url);
//#SuppressWarnings("deprecation")
//WebResource resource = c.resource(sb.toString());
ClientResponse resp = resource.accept("text/html").get(ClientResponse.class);
String xml= null;
if(resp.getStatus() == 200){
xml = resp.getEntity(String.class);
}
return xml;
}
}
I was trying postman with a Java clientava client. I was getting the following output
com.squareup.okhttp.internal.http.RealResponseBody#c9673cf
the original output is
Curl -I "http://ec2-52-34-14-38.us-west-2.compute.amazonaws.com:14000/webhdfs/v1/user/ec2-user/prediction_output/part-00000?user.name=ec2-user&op=OPEN"
1234.566788
here is my java code.
import javax.ws.rs.GET;
import javax.ws.rs.Path;
import javax.ws.rs.Produces;
import javax.ws.rs.core.Response;
import com.squareup.okhttp.OkHttpClient;
import com.squareup.okhttp.Request;
import java.io.IOException;
#Path("/hello")
public class HelloWorldService {
#GET
#Produces("application/json")
public Response getMsg() throws IOException {
OkHttpClient client = new OkHttpClient();
Request request = new Request.Builder()
.url("http://ec2-52-34-14-38.us-west-2.compute.amazonaws.com:14000/webhdfs/v1/user/ec2-user/prediction_output/part-00000?user.name=ec2-user&op=OPEN")
.build();
com.squareup.okhttp.Response responses = null;
responses = client.newCall(request).execute();
System.out.println(responses);
return Response.status(200).entity(responses.body().toString()).build();
}
}
any help will be appreciated.
Use response.body().string() not toString().
Use the above also in System.out.println.
Your method getMsg() says #Produces("application/json") but your built response is text/plain.
I have some problems in my application, I send a POST request, but I cannot retrieve the JsonObject in my server, this is the code to send:
String quo = "{\"network\": {\"label\": \"new net 111\",\"cidr\": \"10.20.105.0/24\"}}";
GsonBuilder builder = new GsonBuilder();
Gson gson = builder.create();
JsonParser json = new JsonParser();
JsonObject jo = (JsonObject)json.parse(quo);
ClientConfig config = new ClientConfig();
Client client = ClientBuilder.newClient(config);
WebTarget target = client.target("http://localhost:7999/jersey/rest/network/"+tenant_id);
Response oj = target.request().accept(MediaType.APPLICATION_JSON)
.header("X-Auth-Token", token)
.post(Entity.json(gson.toJson(jo)));
Trying to retrieve with:
#POST
#Produces(MediaType.APPLICATION_JSON)
#Path("/{tenant_id}")
public String createNetwork(#HeaderParam(value = "X-Auth-Token") String authToken,
#PathParam(value = "tenant_id") String tenant_id,
JsonObject network){
Response response = client.target(NOVA_ENDPOINT+tenant_id)
.request(MediaType.APPLICATION_JSON)
.header("X-Auth-Token", authToken)
.post(Entity.json(gson.toJson(network)));
System.out.println("Hello");
String responseJson = response.readEntity(String.class);
JsonObject network seems to be empty, in fact it doesn't execute the method ("Hello is not printed"), the error I get is "Invalid request body" (because the JsonObject is empty I think)..
What's wrong with my code?
Ok, I understood that the problem is related to Json handling such as I'm using Gson. This is my improved code (simplified version) following users suggestion, but I still have problems..
Client Side:
package openstack;
import javax.ws.rs.client.Client;
import javax.ws.rs.client.ClientBuilder;
import javax.ws.rs.client.Entity;
import javax.ws.rs.client.WebTarget;
import javax.ws.rs.core.Response;
import org.glassfish.grizzly.http.server.HttpServer;
import org.glassfish.jersey.grizzly2.httpserver.GrizzlyHttpServerFactory;
import org.glassfish.jersey.server.ResourceConfig;
import com.google.gson.Gson;
import com.google.gson.GsonBuilder;
import com.google.gson.JsonObject;
import com.google.gson.JsonParser;
import java.net.URI;
public class Post {
public static HttpServer startServer() {
final ResourceConfig resourceConfig = new ResourceConfig()
.packages("openstack")
.register(GsonMessageBodyHandler.class);
return GrizzlyHttpServerFactory.createHttpServer(URI.create("http://localhost:7999/jersey/rest"), resourceConfig);
}
public static void main(String[] args) {
String quo = "{\"keypair\": {\"name\": \"MyKey\"}}";
HttpServer server = startServer();
Client client = ClientBuilder.newClient();
client.register(GsonMessageBodyHandler.class);
GsonBuilder builder = new GsonBuilder();
Gson gson = builder.create();
JsonParser json = new JsonParser();
JsonObject jo = (JsonObject)json.parse(quo);
WebTarget target = client.target("http://localhost:7999/jersey/rest/test/prova");
System.out.println(jo);
Response oj = target.request().post(Entity.json(jo));
String responseString = oj.readEntity(String.class);
System.out.println(responseString);
}
}
Server Side:
package openstack;
import javax.ws.rs.Consumes;
import javax.ws.rs.POST;
import javax.ws.rs.Path;
import javax.ws.rs.Produces;
import javax.ws.rs.client.Client;
import javax.ws.rs.client.ClientBuilder;
import javax.ws.rs.core.MediaType;
import javax.ws.rs.core.Response;
import com.google.gson.Gson;
import com.google.gson.GsonBuilder;
import com.google.gson.JsonObject;
import com.google.gson.JsonParser;
#Path("/test")
public class Test {
GsonBuilder builder = new GsonBuilder();
Gson gson = builder.create();
Parliament parliament = new Parliament();
JsonParser json = new JsonParser();
private final Client client;
public Test() {
client = ClientBuilder.newClient().register(GsonMessageBodyHandler.class);
}
#POST
#Consumes(MediaType.APPLICATION_JSON)
#Produces(MediaType.APPLICATION_JSON)
#Path("/prova")
public Response mymethod(JsonObject keypairsob){
return Response.ok(keypairsob).build();
}
}
I created a GsonMessageBodyHandler.java in my package with the code suggested below by the user peeskillet. Added jersey-container-grizzly2-http.jar to my web-inf/lib (I don't know how to proper use Maven), but still doesn't work.. what am I missing?
In order to convert JSON to a Java type, there is need to for a MessageBodyReader and a MessageBodyWriter implementation to do the conversion to and from. Since you are using JsonObject which is a GSON type, you can see this implementation. There is a problem with the implementation though, as the readFrom method doesn't compile with Jersey 2. Here is the a fixed version
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
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 final class GsonMessageBodyHandler 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 type1, Annotation[] antns,
MediaType mt, MultivaluedMap<String, String> mm, InputStream in)
throws IOException, WebApplicationException {
InputStreamReader streamReader = new InputStreamReader(in, UTF_8);
try {
Type jsonType;
if (type.equals(type1)) {
jsonType = type;
} else {
jsonType = type1;
}
return getGson().fromJson(streamReader, jsonType);
} finally {
streamReader.close();
}
}
#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();
}
}
}
Then we just need to register it with both the client and the application. I'm using a standalone test, where you can see the configuration here
final ResourceConfig resourceConfig = new ResourceConfig()
.packages("jersey.stackoverflow.standalone")
.register(GsonMessageBodyHandler.class);
...
Client c = ClientBuilder.newClient();
c.register(GsonMessageBodyHandler.class);
Here is the resource class I used for the test
import com.google.gson.JsonObject;
import javax.ws.rs.Consumes;
import javax.ws.rs.POST;
import javax.ws.rs.Path;
import javax.ws.rs.Produces;
import javax.ws.rs.client.Client;
import javax.ws.rs.client.ClientBuilder;
import javax.ws.rs.client.Entity;
import javax.ws.rs.core.MediaType;
import javax.ws.rs.core.Response;
import jersey.stackoverflow.standalone.provider.GsonMessageBodyHandler;
#Path("/gson")
public class GsonResource {
private final Client client;
private static final String BASE_URI = "http://localhost:8080/api/gson";
public GsonResource() {
client = ClientBuilder.newClient().register(GsonMessageBodyHandler.class);
}
#POST
#Path("/proxy")
#Consumes(MediaType.APPLICATION_JSON)
#Produces(MediaType.APPLICATION_JSON)
public Response proxyPost(JsonObject json) {
Response response = client.target(BASE_URI)
.path("main-resource").request().post(Entity.json(json));
JsonObject fromMainResource = response.readEntity(JsonObject.class);
return Response.created(null /* should be a created URI */)
.entity(fromMainResource).build();
}
#POST
#Path("/main-resource")
#Consumes(MediaType.APPLICATION_JSON)
#Produces(MediaType.APPLICATION_JSON)
public Response mainResource(JsonObject json) {
return Response.ok(json).build();
}
}
Here's the complete test, which requires this maven dependency
import com.google.gson.Gson;
import com.google.gson.GsonBuilder;
import com.google.gson.JsonObject;
import com.google.gson.JsonParser;
import java.net.URI;
import javax.ws.rs.client.Client;
import javax.ws.rs.client.ClientBuilder;
import javax.ws.rs.client.Entity;
import javax.ws.rs.client.WebTarget;
import javax.ws.rs.core.Response;
import static jersey.stackoverflow.standalone.Main.BASE_URI;
import jersey.stackoverflow.standalone.provider.GsonMessageBodyHandler;
import org.glassfish.grizzly.http.server.HttpServer;
import org.glassfish.jersey.grizzly2.httpserver.GrizzlyHttpServerFactory;
import org.glassfish.jersey.server.ResourceConfig;
import org.junit.Test;
public class GsonProviderTest {
public static HttpServer startServer() {
final ResourceConfig resourceConfig = new ResourceConfig()
.packages("jersey.stackoverflow.standalone")
.register(GsonMessageBodyHandler.class);
return GrizzlyHttpServerFactory.createHttpServer(URI.create(BASE_URI), resourceConfig);
}
public static Client getClient() {
Client c = ClientBuilder.newClient();
c.register(GsonMessageBodyHandler.class);
return c;
}
#Test
public void testGetIt() {
HttpServer server = startServer();
Client c = getClient();
c.register(GsonMessageBodyHandler.class);
String quo = "{\"network\": {\"label\": \"new net 111\",\"cidr\": \"10.20.105.0/24\"}}";
GsonBuilder builder = new GsonBuilder();
Gson gson = builder.create();
JsonParser json = new JsonParser();
JsonObject jo = (JsonObject) json.parse(quo);
WebTarget target = c.target("http://localhost:8080/api/gson/proxy");
Response response = target.request().post(Entity.json(jo));
String responseString = response.readEntity(String.class);
System.out.println(responseString);
response.close();
c.close();
server.stop();
}
}
All the test does is send the JsonObject. Though there isn't any visible conversion to JSON, in any of my code, it is happening behind the scenes by the GsonMessageBodyHandler. If you look at the GsonResource class, you can see the methods don't do anything but send out the JsonObject. In the client test, I read the response as a String, and you can see the result the same as what sent out in the initial request.
See more about MessageBodyReaders and MessageBodyWriters
There's a simple way to get the JsonObject in com.google.gson.JsonObject type using a post request.
I am assuming that all the dependencies for com.google.gson , jersey and jax-rs are already added.
On the server side you need to have code similar to below :
import com.google.gson.JsonObject;
import com.google.gson.JsonParser;
import javax.ws.rs.Consumes;
import javax.ws.rs.POST;
import javax.ws.rs.Path;
import javax.ws.rs.core.Response;
#Path("/api")
public class JersyAPI {
private JsonParser parser= new JsonParser();
#POST
#Path("/pudding")
#Consumes("application/json")
public Response postTest(String requestBody){
Response re = Response.status(200).build();
try{
JsonObject inputObjectJson = parser.parse(requestBody).getAsJsonObject();
The code above has a rest endpoint defined with path /api/pudding and it is accepting the Request Body as String. Once you receive the Json as string on server side, com.google.gson.JsonParser can be used to convert it into the com.google.gson.JsonObject directly and this can be used in your program.
To make a request on server side you post request should look like this :
POST /rest/api/pudding HTTP/1.1
Host: localhost:8082
Content-Type: application/json
Cache-Control: no-cache
Postman-Token: c2b087d9-4830-c8a8-2a19-78273a73898c
{
"id": 1312312,
"name": "Test",
"data": {
"test" : "data"
},
}
Have you had any JSON requests successfully parsed? It could be that you need to enable JSON support in Jersey:
https://jersey.java.net/documentation/1.18/json.html
Otherwise, it may simply be failing on your request to turn the message body into a JsonObject here:
public String createNetwork(
#HeaderParam(value = "X-Auth-Token") String authToken,
#PathParam(value = "tenant_id") String tenant_id,
JsonObject network)
I understand that I can upload 1 file at a time to AppEngine using multipart/form POST requests. AppEngine also supports uploading multiple files but you have to do some hokey JSP stuff for it to work.
I have an app that requires me to upload some form data, 2 images and 3 fields of text. Is this possible to do via AppEngine? I've been trying to find information on this but it's tough nothing works with the flexibility I need. I will be storing the data in the blob store/data store.
I need a Java solution.
This is the signature of my POST method:
import javax.ws.rs.Consumes;
import javax.ws.rs.POST;
#POST
#Consumes(MediaType.MULTIPART_FORM_DATA)
public void post(
#Context HttpServletRequest request,
#Context HttpServletResponse response)
throws FileUploadException, IOException {}
Copy and paste of the Java Servlet if you really need it. Above is the question and relevant servlet snippets.
import java.io.BufferedReader;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.channels.Channels;
import java.util.Iterator;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.ws.rs.Consumes;
import javax.ws.rs.POST;
import javax.ws.rs.Path;
import javax.ws.rs.core.Context;
import javax.ws.rs.core.MediaType;
import org.apache.commons.fileupload.FileItemHeaders;
import org.apache.commons.fileupload.FileItemIterator;
import org.apache.commons.fileupload.FileItemStream;
import org.apache.commons.fileupload.FileUploadException;
import org.apache.commons.fileupload.servlet.ServletFileUpload;
import com.google.appengine.api.blobstore.BlobstoreService;
import com.google.appengine.api.blobstore.BlobstoreServiceFactory;
import com.google.appengine.api.files.AppEngineFile;
import com.google.appengine.api.files.FileReadChannel;
import com.google.appengine.api.files.FileService;
import com.google.appengine.api.files.FileServiceFactory;
import com.google.appengine.api.files.FileWriteChannel;
#Path("/upload")
public class FileUploadServlet {
private BlobstoreService blobstoreService = BlobstoreServiceFactory
.getBlobstoreService();
#POST
#Consumes(MediaType.MULTIPART_FORM_DATA)
public void post(#Context HttpServletRequest request,
#Context HttpServletResponse response) throws FileUploadException,
IOException {
final ServletFileUpload upload = new ServletFileUpload();
final FileItemIterator fileIter = upload.getItemIterator(request);
while (fileIter.hasNext()) {
final FileItemStream item = fileIter.next();
String name = item.getName();
String fieldName = item.getFieldName();
String contentType = item.getContentType();
Log.d("Name = " + name);
Log.d("Field-Name = " + fieldName);
Log.d("Content-Type = " + contentType);
FileItemHeaders headers = item.getHeaders();
if(headers != null) {
Iterator<String> it = (Iterator<String>)headers.getHeaderNames();
while(it.hasNext()) {
String h = it.next();
Log.d(h + " = " + headers.getHeader(h));
}
}
if (item.isFormField()) {
// Nothing
} else {
RawImageData data = new RawImageData();
data.load(item.openStream());
// RawImageData reads the stream and stores it into a large byte[] called data.imageData
ByteBuffer bb = ByteBuffer.wrap(data.imageData);
FileService fs = FileServiceFactory.getFileService();
AppEngineFile file = fs.createNewBlobFile(contentType);
FileWriteChannel write = fs.openWriteChannel(file, true);
write.write(bb);
write.closeFinally();
String path = file.getFullPath();
Log.d(path);
// Later, read from the file using the file API
boolean lock = false; // Let other people read at the same time
FileReadChannel readChannel = fs.openReadChannel(file,
false);
// CRASHES WITH java.nio.charset.IllegalCharsetNameException: image/jpeg
// contentType = "image/jpeg"
// Again, different standard Java ways of reading from the
// channel.
BufferedReader reader = new BufferedReader(Channels.newReader(readChannel, contentType));
readChannel.close();
}
}
response.setContentType("text/html");
response.getOutputStream().write("success".getBytes());
}
}
Full Exception:
WARNING: /api/upload
java.nio.charset.IllegalCharsetNameException: image/jpeg
at java.nio.charset.Charset.checkName(Charset.java:284)
at java.nio.charset.Charset.lookup2(Charset.java:458)
at java.nio.charset.Charset.lookup(Charset.java:437)
at java.nio.charset.Charset.forName(Charset.java:502)
at java.nio.channels.Channels.newReader(Channels.java:381)
at com.futonredemption.starstarstar.FileUploadServlet.post(FileUploadServlet.java:96)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
blah blah blah
You can create you own multipart file upload handler, then save files via Blobstore FileService API.