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Soap Webservice Client for JAVAFX Application

I am trying to call the webservice for my application. If I call it in a sample project it is working perfectly fine. But when I merge it with My Java FX it is giving me so many errors. Web Service Client is auto generated using the Eclipse. I am trying to call the Methods only. Can Anyone help me?
Error: **Correction** I have edited it and I am using now JAVASE-15 and JVAFX-SDK 11.0.2
The package javax.xml.namespace is accessible from more than one module: java.xml, jaxrpc
Correction Update 2: I have removed Java.xml dependencies and module-info file as well.
but the new error is this
**Error: Could not find or load main class gload.Main
Caused by: java.lang.NoClassDefFoundError: javafx/application/Application**
and IF I keep the module info file it shows:
**Error occurred during initialization of boot layer
java.lang.module.FindException: Module javafx.graphics not found, required by gload**
Model:
package gload.model;
import java.io.File;
import java.io.FileInputStream;
import java.io.FilenameFilter;
import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.nio.file.StandardCopyOption;
import java.util.zip.ZipEntry;
import java.util.zip.ZipInputStream;
import javax.swing.JOptionPane;
import org.apache.pdfbox.pdmodel.PDDocument;
import org.apache.pdfbox.text.PDFTextStripper;
import org.datacontract.schemas._2004._07.PE_PPER_MyPdmWebServiceClient_Data.CustomerItem;
import org.datacontract.schemas._2004._07.PE_PPER_MyPdmWebServiceClient_Data.Result;
import org.tempuri.IService;
import org.tempuri.ServiceLocator;
public class PdmData
{
public String scode;
public boolean state = false;
public static String CdfFile;
public static String pdflocation;
public static String Custom_Ci;
public static String Generic_Ci;
public static String Mp_ref;
public static String Interface;
public static String Comments;
public static String PersoAppli;
public static String Code;
public static String Revision;
public static String Customer_Name;
public static String Customer_reference;
public static String getCode() {
return Code;
}
public static void setCode(String code) {
Code = code;
}
public static String getRevision() {
return Revision;
}
public static void setRevision(String revision) {
Revision = revision;
}
public static String getCustomer_Name() {
return Customer_Name;
}
public static void setCustomer_Name(String customer_Name) {
Customer_Name = customer_Name;
}
public static String getCustomer_reference() {
return Customer_reference;
}
public static void setCustomer_reference(String customer_reference) {
Customer_reference = customer_reference;
}
public static String getPersoAppli() {
return PersoAppli;
}
public static void setPersoAppli(String persoAppli) {
PersoAppli = persoAppli;
}
public static String getGeneric_Ci() {
return Generic_Ci;
}
public static void setGeneric_Ci(String generic_Ci) {
Generic_Ci = generic_Ci;
}
public static String getCdfFile() {
return CdfFile;
}
public static void setCdfFile(String cdfFile) {
CdfFile = cdfFile;
}
public static String getPdflocation() {
return pdflocation;
}
public static void setPdflocation(String pdflocation) {
PdmData.pdflocation = pdflocation;
}
public String Cdffile(String reference) {
ServiceLocator locator = new ServiceLocator(); -------->Web Service Locator and call
try {
IService basicHttpBinding_IService = locator.getBasicHttpBinding_IService();
Result result = basicHttpBinding_IService.getFilebyDcode(reference);
//To download the files
String link = result.getLocation();
System.out.println(link);
File out = new File("C:\\TempDownload\\" + reference +".zip"); //Creating a zip file to store the contents of download file
new Thread(new Download(link,out)).start();
//To Unzip the file
Path source = Paths.get("C:\\TempDownload\\" + reference +".zip");
Path target = Paths.get("C:\\TempDownload\\Unzip");
try {
unzipFolder(source, target);
System.out.println("Done");
} catch (IOException e) {
e.printStackTrace();
}
//Creating a File object for directory
File directoryPath = new File("C:\\TempDownload\\Unzip\\Pre Ppc" + reference + "A_Released");
//List of all files and directories
String[] contents = directoryPath.list();
System.out.println("List of files and directories in the specified directory:");
FilenameFilter pdffilter = new FilenameFilter() {
public boolean accept(File dir, String name) {
String lowercaseName = name.toLowerCase();
if (lowercaseName.endsWith(".pdf")) {
return true;
} else {
return false;
}
}
};
String[] contents1 = directoryPath.list(pdffilter);
for(String fileName : contents1) {
System.out.println(fileName);
setCdfFile(fileName);
setPdflocation(directoryPath.toString());
}
//To extract the Data From PDF
File file = new File(getPdflocation() + "\\" + getCdfFile());
//FileInputStream fis = new FileInputStream(file);
PDDocument document = PDDocument.load(file);
PDFTextStripper pdfReader = new PDFTextStripper();
String docText = pdfReader.getText(document);
System.out.println(docText);
document.close();
//To extract details from document
String CI_Ref = "CI Ref";
int pos ;
pos = docText.indexOf(CI_Ref);
setGeneric_Ci(docText.substring(pos+7 , pos+15));
System.out.println("Generic CI: " + getGeneric_Ci());
//To get Details of CI
CustomerItem customerItem = basicHttpBinding_IService.getCiDetails(getGeneric_Ci());
setPersoAppli(customerItem.getPersoAppli());
setCode(customerItem.getCode());
setRevision(customerItem.getRevision());
setCustomer_Name(customerItem.getCustomerName());
setCustomer_reference(customerItem.getCustomerReference());
}catch (Exception e) {
e.printStackTrace();
JOptionPane.showMessageDialog(null, "Unable to reach Service : " + e.getMessage());
}
return getPersoAppli();
}
Module info file
module gload {
requires javafx.controls;
requires javafx.fxml;
requires java.desktop;
requires java.rmi;
requires java.base;
requires axis;
requires jaxrpc;
requires org.apache.pdfbox;
opens gload;
opens gload.views.main;
opens gload.utils;
opens gload.model;
opens gload.controllers;
opens org.tempuri;
opens org.datacontract.schemas._2004._07.PE_PPER_MyPdmWebServiceClient_Data;
}
and IF I keep Jaxrpc in classpath instead of module path I get error like this Description
The type javax.xml.rpc.ServiceException cannot be resolved. It is indirectly referenced from required .class files

OK, this won't really be an answer, more pointers to related issues and potential approaches to come up with solutions. But I'll post it as an answer as it is likely better to do that than lots of comments.
Unfortunately, you have multiple errors and issues, so I'll try to deal with some of them seperately.
According to:
Java FX Modular Application, Module not found (Java 11, Intellij)
The error:
Error occurred during initialization of boot layer
java.lang.module.FindException:
Module X not found, required by Y
can occur when --module-path is wrong and the module can't be found. Probably, that is at least one of your issues. The linked answer is for Idea and I don't use Eclipse, so I don't know how to resolve the issue in Eclipse, but perhaps you could do some research to find out.
Regarding:
The package javax.xml.namespace is accessible from more than one module
there is some info on what is going on here:
Eclipse is confused by imports ("accessible from more than one module").
This fix appears tricky to me. Please review the linked questions and solutions. It looks like either you need to either
Forego Java 9+ modularity OR
Manage your dependencies to not include the violating transitive dependency OR
Change to a library that doesn't rely on the broken library (probably the preferred solution in this case).
The broken library causing this issue is likely the version of jaxrpc you are using. My guess is that some of the relevant XML libraries were only added to standard Java in Java 9, but the jaxrpc library you are using was developed prior to that. So, jaxrpc either includes the XML libraries in its classes or makes use of a transitive library that does the same. This causes a conflict because the XML libraries can only be included once in the project.
Further info on your issues is in this answer:
Eclipse can't find XML related classes after switching build path to JDK 10
The info is so ugly . . . you could read the answer, it may either help or discourage you.
Some things you could do to help resolve the situation
What should be done about this is kind of tricky and will depend on your skill level and how or if you can solve it. I'll offer up some advice on some things you could do, but there are other options. You know your application better than I so you may be able to come up with better solutions for your application.
I'd advise separating these things out, just as a way of troubleshooting, get a project which works with all of the JavaFX components and one which works with all of the SOAP components and make sure they build and do what you want. Then try to combine the two projects either by integrating them into one project or running them in separate VMs with communication between the two (e.g. via an added REST API, though that is a much more complicated solution, so think hard about that before attempting it).
Also, upgrade to the latest version of JavaFX. I don't think it will fix your issue, but it can't hurt and it is possible some refinements in recent JavaFX versions may have done some things which might help ease some of your issues (though not all of them, as some of your issues stem from jaxrpc usage in a modular project, which is unrelated to JavaFX).
Also, and probably more importantly, consider using a different SOAP client framework that interacts better with modular Java 9+ than the broken implementation that jaxrpc appears to have.
In terms of whether you should make your application modular or not (include a module-info or not), I don't really know the best approach for you. Certainly, whichever way you choose you will run into issues. But, the issues and how to resolve them will be different depending on the chosen solution path (as I guess you have already discovered during the course of your investigation for the question).
If necessary, isolate the issues down to single separate issues. If you need help in resolving each separate issue post new questions that feature minimal reproducible example code to replicate the issue. Mind if you do so, that the code is absolutely minimal and also complete so that it replicates and asks about only one issue, not a combination of more than one and that the questions are appropriate tagged - e.g. if the question is about jaxrpc and modularity it should include jaxrpc and modular tags and no JavaFX code or tags (and vice versa) and certainly on pdf code or dependencies anywhere if that isn't part of the problem.

JNI Unsatisfied Link Error when calling the methods of one class but not the other

I want to wrap a C++ library (PCL) in Java code using JNI, but I am having inconsistent results. I have first created a PointXYZ class for testing and it looks like this:
package pcl;
public class PointXYZ extends NativeObject {
PointXYZ() { }
#Override
public native void alloc(); // creates pointer + handle on the native side
#Override
public native void dispose(); // sets handle to 0 and deletes pointer
public native float getX();
// ...
}
I have generated the C header for this class using javah, compiled everything using CMake, tested it using its getters and setters and everything works perfectly.
static {
System.setProperty("java.library.path", System.getProperty("user.dir") + "/lib");
System.loadLibrary("pcl_java_common");
}
#Test
void attributeAccessTest() {
PointXYZ p = new PointXYZ();
p.alloc();
p.setX(3);
assertEquals(p.getX(), 3);
p.dispose();
// all is good
}
Now I have done the exact same steps for a PointXYZRGB class which inherits from PointXYZ and when I try to test that it throws java.lang.UnsatisfiedLinkError. Here is the class:
package pcl;
public class PointXYZRGB extends PointXYZ {
public PointXYZRGB() { }
#Override
public native void alloc();
#Override
public native void dispose();
public native short getR();
// ...
}
I have checked the generated .dll using Dependency Walker and the PointXYZRGB methods are all present. Anyone knows what the problem could be?
UPDATE: Here are the .dll functions as requested in the comment:

The problem was that System.setProperty("java.library.path", System.getProperty("user.dir") + "/lib"); does not actually make Java look for .dll files in the given path. It essentially does nothing. Then why do the tests work for PointXYZ? This is was my mistake of having put an older .dll into the project root folder, so it was essentially looking for methods in that.

Call DLL from Java using JNA

I am new to accessing DLLs from Java using JNA. I need to access methods from a class within a DLL(written in .net). Form this sample DLL below, I am trying to get AuditID and Server ID. I am ending with the following error while I am running my code. Any guidance really appreciated.
/// Error ///
Exception in thread "main" java.lang.UnsatisfiedLinkError: Error looking up function 'GetEnrollcontext': The specified procedure could not be found.
//DLL File Code//
SampleDLL.ProfileEnroll enrollcontext = new SampleDLL.ProfileEnroll();
enrollcontext.Url =” url”;
enrollcontext.AuditIdType = SampleDLL.ProfileId;
enrollcontext.AuditId = “22222222 “;
enrollcontext.ServerId = “server1”;
/// Java Code ///
import com.sun.jna.Library;
import com.sun.jna.Native;
import com.sun.jna.Structure;
import dllExtract.DLLExtractTest.SampleDLL.Enrollcontext;
public class SampleDLLExtract {
public interface SampleDLL extends Library {
SampleDLL INSTANCE = (SampleDLL) Native.loadLibrary("SampleDLL",
SampleDLL.class);
public static class Enrollcontext extends Structure {
public String auditId;
public String serverId;
}
void GetEnrollcontext(Enrollcontext ec); // void ();
}
public static void main(String[] args) {
SampleDLL sdll = SampleDLL.INSTANCE;
SampleDLL.Enrollcontext enrollContext = new SampleDLL.Enrollcontext();
sdll.GetEnrollcontext(enrollContext);
System.out.println(sdll.toString(sdll.GetEnrollcontext(enrollContext)));
}
}

in fact there is a solution for you to use C#, VB.NET or F# code via JNA in Java (and nothing else)! and it is also very easy to use:
https://www.nuget.org/packages/UnmanagedExports
with this package all you need to do is, add [RGiesecke.DllExport.DllExport] to your methods like that:
C# .dll Project:
[RGiesecke.DllExport.DllExport]
public static String yourFunction(String yourParameter)
{
return "CSharp String";
}
Java Project:
public interface jna extends Library {
jna INSTANCE = (jna) Native.loadLibrary("yourCSharpProject.dll", jna.class);
public String yourFunction(String yourParameter);
}
use it in the code:
System.out.println(jna.INSTANCE.yourFunction("nothingImportant"));
Viola!
As already mentioned it works very easy, but this solution has some limitations:
only available for simple datatypes as parameter & return values
no MethodOverloading available. yourFunction(String yourParameter) and yourFunction(String yourParameter, String yourSecondParameter) does not work! you have to name them differently
Use arrays as parameter or return values. (JNA offers StringArray, but I am not able to use them in C#) (maybe there is a solution, but I couldn't come up with one so far!)
if you export a method you can't call it internally in your C# code (simple to bypass that by the following:
.
[RGiesecke.DllExport.DllExport]
public static Boolean externalAvailable(String yourParameter)
{
return yourInternalFunction(yourParameter);
}
With C# it works great, with VB.NET and F# I have no experience.
hope this helps!

Java structure/pattern(s) to return specific field from subclasses

For a project we have a requirement to create an interfacedefinition that will return all available filetype extensions that our component can export...
The problem is that we want avoid configuration/properties files. We don't want to edit our configuration/propertie file when another filetype is added (in the future). The structure of this part of our component is as follows:
public abstract class FileType {
protected String filetype;
public FileType(String filetype){
this.filetype = filetype;
}
public abstract void export(String path, Object information);
}
public class PdfExport extends FileType {
public PdfExport() {
super("pdf");
}
public void export(String path, Object information){
//pdf specific logic
}
}
But how do we solve this when another component calls the interfacedefinition getExportTypes()? (How do we get a list of all available filetypes?) Taking into account the requirement to add in the future new classes that extend abstract class filetype (add new filetypes)?
Does anyone has suggestions, maybe another structure of above example? Or any (design) that discuss above issue?
Thanks in advance!

You could do something like this:
public interface FileType {
public String getFileType();
public void export(String path, Object info);
}
public enum DefaultFileType implements FileType {
PDF(".pdf"){
public void export(String path, Object info) {
// do pdf stuff
}
}, TXT(".txt"){
public void export(String path, Object info) {
//do txt stuff
}
};
private final String fileType;
private DefaultFileType(String fileType) {
this.fileType = fileType;
}
public String getFileType() {
return fileType;
}
public abstract void export(String path, Object info);
}
Then you can have a Set<FileType> in your class of all the supported FileTypes. This way anyone who wants to add a supported FileType but cannot edit your enum can still do so.

This is the exact purpose of the strategy pattern. The strategies here are the FileTypes that encapsulate an algorithm that exports a file.
In the following example:
public class Application{
List<FileType> exporters = new ArrayList<FileType>();
public void addExporter(FileType fileExporter){
exporters.add(fileExporter);
}
public void exportData(Object information){
for(FileType exporter : exporters){
exporter.export("d:\Export", information);
}
}
}
The Application class holds a list of exporters that can be filled out on the go. The Application class does not have to know what type of file exporter is registered nor how the file can be exported. When the data is exported, the Applicaiton class loops through registered exporters and delegates the export task to each one of them.
EDIT Below is an example of the Application class usage.
// Define a pdf exporter
PdfExport pdfExport = new pdfExport();
Application app = new Application();
// Register the new exporter
app.addExporter(pdfExport);
// Export some data...
app.export(information);
EDIT How to avoid configuration files and changing the code everytime you have a new FileType?
You can load the exporters at runtime using reflexion (see this link for details)

You can use reflection to scan classes which implement your interface.
Have a look at similar question: At runtime, find all classes in a Java application that extend a base class

Problems passing class objects through GWT RPC

I've run through the Google Web Toolkit StockWatcher Tutorial using Eclipse and the Google Plugin, and I'm attempting to make some basic changes to it so I can better understand the RPC framework.
I've modified the "getStocks" method on the StockServiceImpl server-side class so that it returns an array of Stock objects instead of String objects. The application compiles perfectly, but the Google Web Toolkit is returning the following error:
"No source code is available for type com.google.gwt.sample.stockwatcher.server.Stock; did you forget to inherit a required module?"
It seems that the client-side classes can't find an implementation of the Stock object, even though the class has been imported. For reference, here is a screenshot of my package hierarchy:
I suspect that I'm missing something in web.xml, but I have no idea what it is. Can anyone point me in the right direction?
EDIT: Forgot to mention that the Stock class is persistable, so it needs to stay on the server-side.

After much trial and error, I managed to find a way to do this. It might not be the best way, but it works. Hopefully this post can save someone else a lot of time and effort.
These instructions assume that you have completed both the basic StockWatcher tutorial and the Google App Engine StockWatcher modifications.
Create a Client-Side Implementation of the Stock Class
There are a couple of things to keep in mind about GWT:
Server-side classes can import client-side classes, but not vice-versa (usually).
The client-side can't import any Google App Engine libraries (i.e. com.google.appengine.api.users.User)
Due to both items above, the client can never implement the Stock class that we created in com.google.gwt.sample.stockwatcher.server. Instead, we'll create a new client-side Stock class called StockClient.
StockClient.java:
package com.google.gwt.sample.stockwatcher.client;
import java.io.Serializable;
import java.util.Date;
public class StockClient implements Serializable {
private Long id;
private String symbol;
private Date createDate;
public StockClient() {
this.createDate = new Date();
}
public StockClient(String symbol) {
this.symbol = symbol;
this.createDate = new Date();
}
public StockClient(Long id, String symbol, Date createDate) {
this();
this.id = id;
this.symbol = symbol;
this.createDate = createDate;
}
public Long getId() {
return this.id;
}
public String getSymbol() {
return this.symbol;
}
public Date getCreateDate() {
return this.createDate;
}
public void setId(Long id) {
this.id = id;
}
public void setSymbol(String symbol) {
this.symbol = symbol;
}
}
Modify Client Classes to Use StockClient[] instead of String[]
Now we make some simple modifications to the client classes so that they know that the RPC call returns StockClient[] instead of String[].
StockService.java:
package com.google.gwt.sample.stockwatcher.client;
import com.google.gwt.sample.stockwatcher.client.NotLoggedInException;
import com.google.gwt.user.client.rpc.RemoteService;
import com.google.gwt.user.client.rpc.RemoteServiceRelativePath;
#RemoteServiceRelativePath("stock")
public interface StockService extends RemoteService {
public Long addStock(String symbol) throws NotLoggedInException;
public void removeStock(String symbol) throws NotLoggedInException;
public StockClient[] getStocks() throws NotLoggedInException;
}
StockServiceAsync.java:
package com.google.gwt.sample.stockwatcher.client;
import com.google.gwt.sample.stockwatcher.client.StockClient;
import com.google.gwt.user.client.rpc.AsyncCallback;
public interface StockServiceAsync {
public void addStock(String symbol, AsyncCallback<Long> async);
public void removeStock(String symbol, AsyncCallback<Void> async);
public void getStocks(AsyncCallback<StockClient[]> async);
}
StockWatcher.java:
Add one import:
import com.google.gwt.sample.stockwatcher.client.StockClient;
All other code stays the same, except addStock, loadStocks, and displayStocks:
private void loadStocks() {
stockService = GWT.create(StockService.class);
stockService.getStocks(new AsyncCallback<String[]>() {
public void onFailure(Throwable error) {
handleError(error);
}
public void onSuccess(String[] symbols) {
displayStocks(symbols);
}
});
}
private void displayStocks(String[] symbols) {
for (String symbol : symbols) {
displayStock(symbol);
}
}
private void addStock() {
final String symbol = newSymbolTextBox.getText().toUpperCase().trim();
newSymbolTextBox.setFocus(true);
// Stock code must be between 1 and 10 chars that are numbers, letters,
// or dots.
if (!symbol.matches("^[0-9a-zA-Z\\.]{1,10}$")) {
Window.alert("'" + symbol + "' is not a valid symbol.");
newSymbolTextBox.selectAll();
return;
}
newSymbolTextBox.setText("");
// Don't add the stock if it's already in the table.
if (stocks.contains(symbol))
return;
addStock(new StockClient(symbol));
}
private void addStock(final StockClient stock) {
stockService.addStock(stock.getSymbol(), new AsyncCallback<Long>() {
public void onFailure(Throwable error) {
handleError(error);
}
public void onSuccess(Long id) {
stock.setId(id);
displayStock(stock.getSymbol());
}
});
}
Modify the StockServiceImpl Class to Return StockClient[]
Finally, we modify the getStocks method of the StockServiceImpl class so that it translates the server-side Stock classes into client-side StockClient classes before returning the array.
StockServiceImpl.java
import com.google.gwt.sample.stockwatcher.client.StockClient;
We need to change the addStock method slightly so that the generated ID is returned:
public Long addStock(String symbol) throws NotLoggedInException {
Stock stock = new Stock(getUser(), symbol);
checkLoggedIn();
PersistenceManager pm = getPersistenceManager();
try {
pm.makePersistent(stock);
} finally {
pm.close();
}
return stock.getId();
}
All other methods stay the same, except getStocks:
public StockClient[] getStocks() throws NotLoggedInException {
checkLoggedIn();
PersistenceManager pm = getPersistenceManager();
List<StockClient> stockclients = new ArrayList<StockClient>();
try {
Query q = pm.newQuery(Stock.class, "user == u");
q.declareParameters("com.google.appengine.api.users.User u");
q.setOrdering("createDate");
List<Stock> stocks = (List<Stock>) q.execute(getUser());
for (Stock stock : stocks)
{
stockclients.add(new StockClient(stock.getId(), stock.getSymbol(), stock.getCreateDate()));
}
} finally {
pm.close();
}
return (StockClient[]) stockclients.toArray(new StockClient[0]);
}
Summary
The code above works perfectly for me when deployed to Google App Engine, but triggers an error in Google Web Toolkit Hosted Mode:
SEVERE: [1244408678890000] javax.servlet.ServletContext log: Exception while dispatching incoming RPC call
com.google.gwt.user.server.rpc.UnexpectedException: Service method 'public abstract com.google.gwt.sample.stockwatcher.client.StockClient[] com.google.gwt.sample.stockwatcher.client.StockService.getStocks() throws com.google.gwt.sample.stockwatcher.client.NotLoggedInException' threw an unexpected exception: java.lang.NullPointerException: Name is null
Let me know if you encounter the same problem or not. The fact that it works in Google App Engine seems to indicate a bug in Hosted Mode.

GWT needs the .java file in addition to the .class file. Additionally, Stock needs to be in the "client" location of a GWT module.

The GWT compiler doesn't know about Stock, because it's not in a location it looks in. You can either move it to the client folder, or if it makes more sense leave it where it is and create a ModuleName.gwt.xml that references any other classes you want, and get your Main.gwt.xml file to inherit from that.
eg: DomainGwt.gwt.xml
<module>
<inherits name='com.google.gwt.user.User'/>
<source path="javapackagesabovethispackagegohere"/>
</module>
and:
<module rename-to="gwt_ui">
<inherits name="com.google.gwt.user.User"/>
<inherits name="au.com.groundhog.groundpics.DomainGwt"/>
<entry-point class="au.com.groundhog.groundpics.gwt.client.GPicsUIEntryPoint"/>
</module>

There's a better answer here: GWT Simple RPC use case problem : Code included
Basically, you can add parameters to your APPNAME.gwt.xml file so the compiler to give the compiler a path to the server-side class.

I was getting the same issue and the "mvn gwt:compile" output was not very helpful.
Instead, when I tried deploying to tomcat (via the maven tomcat plugin: mvn tomcat:deploy) I got helpful error messages.
A few things I had to fix up:
Make the object that is sent from the client to the server implement Serializable
Add an empty-arg constructor to that same object

Yes, it is sure that we need to use the Serialization for getting the server objects to the client. These modile?? file settings won't work to use the Stock class in the client side.
In your case you have only one class Stock and you can create a StockClient in client side. It is easy. But what will be the solution if anyone having more classes. Something like the properties of this class are also some other type of classes.
Example: stock.getEOD(date).getHigh();
getEOD will return another class with the given date and that class has the getHigh method.
What to do in such big cases? I don't think creating all classes implementing serialization in client side is good for that. Then we have to write code in both server and client. all classes two times.

Keying off of rustyshelf's answer above ...
In my case I needed to edit the ModuleName.gwt.xml file and add the following:
<source path='client'/>
<source path='shared'/>
I created my project with the New->Web Application Project wizard but unchecked the Generate project sample code option. I then created the shared package. Had I not unchecked that, the package would have been created for me and the xml file modified per the above.

There is a far more simple and easy solution for that. If you want to send an object of your custom designed class from server side to client side you should define this custom class in shared package.
For example for your case the you just have to carry the Stock.java class (by drag and drop) into
com.google.gwt.sample.stockwatcher.shared
package. However from your package hierarchy screenshot it seems that you had deleted this shared package. Just re-create this package and drop the Stock.java inside it and let the game begin.