This short
example demonstrates us, how javafx works as a client, in an application having
a client-server arhitecture. The tutorial uses the following softwares and
tools, and if you wish to try it, you should have installed, these on your
computer:
-
Oracle Database Express Edition 11g Release
-
Java SE Development Kit 7
JavaFX SDK is now included in the JDK 7 for Windows, Mac
OS X, and Linux x86/x64.
-
Netbeans 7.2 Development IDE
(http://netbeans.org/downloads/index.html). Download the Java EE or the full
version of Netbeans. This setup will install to your computer the Apache Tomcat
and also the Glassfish Server if you check these options. In this tutorial we
use just the Tomcat Apache Server 7.0.27.
-
JDBC Driver to the Oracle Database Express Edition 11g
Web services are Web based applications
that use open, XML-based standards and transport protocols to exchange data
with clients. Web services are developed using Java Technology APIs and tools
provided by an integrated Web Services Stack called Metro. The Metro library
package is also installed on your computer by Netbeans.
JavaFX
is the next step in the evolution of Java as a rich client platform. It is
designed to provide a lightweight, hardware-accelerated Java UI platform for
enterprise business applications. With JavaFX, developers can preserve existing
investments by reusing Java libraries in their applications. They can even
access native system capabilities, or seamlessly connect to server-based
middleware applications.
FYI:
You can use also your favorite IDE
instead of Netbeans, but you must ensure that the additional packages(Tomcat,
Metro), are also installed.
After having installed all the software
and tools, we will have 3 more steps to do, first database operations, then
creating the web service in Netbeans, and finally the client part programming,
javafx.
1. Database tasks
The example is about storing information
about books, read by me, and retrieving information from database by a given
book id, and presenting them by javafx client, through a webservice. In the
database we will have a book table, with the fields: Id, Title and Writer. To
increment the primary key at every new record, in the book table, we use triggers
and sequences in Oracle. You should use, the free SQLDeveloper tool. (http://www.oracle.com/technetwork/developer-tools/sql-developer/downloads/index.html).
The sql code for creating a login user, the table, sequence, and trigger, are
the following:
Login user
-- Create the user
create user TESTER
identified by ""
default tablespace SYSTEM
temporary tablespace TEMP
profile DEFAULT
password expire;
-- Grant/Revoke role privileges
grant dba to TESTER;
-- Grant/Revoke system privileges
grant unlimited tablespace to TESTER;
Create table
-- Create table
create table BOOK
(
ID NUMBER not null,
TITLE NVARCHAR2(50) not null,
WRITER NVARCHAR2(100)
)
tablespace SYSTEM
pctfree 10
pctused 40
initrans 1
maxtrans 255
storage
(
initial 64K
next 1M
minextents 1
maxextents unlimited
);
-- Add comments to the table
comment on table BOOK
is
'Testing javafx and webservice';
-- Add comments to the columns
comment on column BOOK.ID
is
'Primary key';
comment on column BOOK.TITLE
is
'Title of the book';
comment on column BOOK.WRITER
is
'Writer of the book';
-- Create/Recreate primary, unique and
foreign key constraints
alter table BOOK
add constraint PK_ID primary key (ID)
using index
tablespace SYSTEM
pctfree 10
initrans 2
maxtrans 255
storage
(
initial 64K
next 1M
minextents 1
maxextents unlimited
);
Create sequence
-- Create sequence
create sequence SEQ_BOOK
minvalue 1
maxvalue 9999999999999999999999999999
start with 1
increment by 1
cache 20;
Create trigger
create or replace trigger TRG_BOOK
before insert on book
for each row
declare
--
local variables here
begin
IF INSERTING THEN
IF
:NEW.ID IS NULL THEN
SELECT SEQ_BOOK.NEXTVAL INTO :NEW.ID FROM DUAL;
END IF;
END
IF;
end TRG_BOOK;
/
2. Creating the Webservice
Using the Netbeans IDE, to create a
webservice, is very easy. First you create a Web Application, by doing: File-New
Web Application in Netbeans' Menu. In this demo, we use the Apache Tomcat
7.0.27. as a webserver for our web application. Netbeans 7.2 IDE allows you to
choose this webserver, when you create the web application. After the first
step we easyly create the webservice, just right clicking on project
source and saying, create webservice. Name your webservice(class), WebServcieForJavaFx. Then Netbeans will create you, also a simple “hello” example method,
that we will change to the method GetBookInfo.
The GetBookInfo() function will retrieve the
informations, book title and writer from database, by an ID. The ID will be an
input parameter to this method, and the return type of this function will be a special
type, created by us: RecordType. Because the program works with Oracle database you must also add
the oracle jdbc driver to this project. Right click at the project and at the
Properties you can add the ojdbc6.jar file.
First let’s see the special return type,
the RecordType java class file, how it looks:
package utils;
/**
*
* @author Sipos Lehel
*/
public class
RecordType {
private String Title;
private String Writer;
RecordType() {
}
public String getTitle() {
return Title;
}
public void setTitle(String Title) {
this.Title = Title;
}
public String getWriter() {
return Writer;
}
public void setWriter(String Writer) {
this.Writer = Writer;
}
}
And then the webservice main class will
be the following:
package server;
import
java.sql.Connection;
import
java.sql.DriverManager;
import
java.sql.Statement;
import
java.sql.ResultSet;
import
javax.jws.WebService;
import
javax.jws.WebMethod;
import
javax.jws.WebParam;
import utils.*;
/**
*
* @author Sipos Lehel
*/
@WebService(serviceName
= "WebServiceForJavaFx")
public class
WebServiceForJavaFx {
@WebMethod(operationName =
"GetBookInfo")
public RecordType
GetBookInfo(@WebParam(name = "strID") String strID) {
RecordType answer = new RecordType();
answer.setTitle("empty");
answer.setWriter("empty");
try {
Class.forName("oracle.jdbc.OracleDriver");
Connection con =
DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:XE",
"tester", "tester");
ResultSet rs = null;
Statement stmt = con.createStatement();
rs=stmt.executeQuery("select
* from book where ID="+strID);
if (rs!=null) {
rs.next();
answer.setTitle(rs.getString("TITLE"));
answer.setWriter(rs.getString("WRITER"));
rs.close();
}
stmt.close();
} catch (Exception ex) {
answer.setTitle(ex.getMessage());
answer.setWriter("Error
occured!");
}
return answer;
}
}
A webservice publishes it’s method
through a WSDL file, and therefore right click in Netbeans, at webservice and
say generate WSDL file. Start your webservice, by running this application. You
can test the web service information by also, right clicking in Netbeans:
3. Programming JavaFx – webservice client
To create a javafx
application in Netbeans, just simply say, File-New Project-JavaFx-Create JavaFx
Application. Call your java main file in this project: WebClientJavaFx.
Creating a webservice client at the
second step, is also very easy, just right click your source in the Projects
window and say create web service client. Creating your webservice client you
will need to point the WSDL location, which you can do by specifying its URL:
In the java source file you can call the
Web Service Operation in your start method, by right clicking in the netbeans
source editor, and saying Insert Code and then Call Web Service Operation.
We will have 3 components to work with,
a button to call the webservice, a label to see the answer, and a field component
to bypass the ID input parameter to the webservice method.
Your WebClientJavaFx
java file, after programming should look like this:
package
webclientjavafx;
import
javafx.application.Application;
import
javafx.event.ActionEvent;
import
javafx.event.EventHandler;
import
javafx.scene.Group;
import
javafx.scene.Scene;
import
javafx.scene.control.Button;
import javafx.scene.control.Label;
import
javafx.scene.control.TextField;
import
javafx.stage.Stage;
import
webclientjavafx.webclient.RecordType;
/**
*
* @author Sipos Lehel
*/
public class
WebClientJavaFx extends Application {
Label lbl = new Label("Lehel Sipos
read: ");
TextField fld = new
TextField("2");
RecordType answ;
@Override
public void start(Stage primaryStage)
{
answ =
getBookInfo("2");
Button btn = new Button();
btn.setText("Get a book from the
shelf");
btn.setOnAction(new
EventHandler<ActionEvent>() {
@Override
public void handle(ActionEvent
event) {
answ =
getBookInfo(fld.getText());
lbl.setText("Lehel Sipos
read: "+answ.getTitle()+" "+answ.getWriter());
}
});
Group root = new Group();
root.getChildren().add(0,lbl);
root.getChildren().add(1,fld);
root.getChildren().add(2,btn);
root.getChildren().get(0).setLayoutX(50);
root.getChildren().get(0).setLayoutY(10);
root.getChildren().get(1).setLayoutX(50);
root.getChildren().get(1).setLayoutY(40);
root.getChildren().get(2).setLayoutX(50);
root.getChildren().get(2).setLayoutY(100);
Scene scene = new Scene(root, 600,
250);
primaryStage.setTitle("JavaFx-Webservice example");
primaryStage.setScene(scene);
primaryStage.show();
}
public static void main(String[] args) {
launch(args);
}
private static RecordType
getBookInfo(java.lang.String strID) {
webclientjavafx.webclient.WebServiceForJavaFx_Service service = new
webclientjavafx.webclient.WebServiceForJavaFx_Service();
webclientjavafx.webclient.WebServiceForJavaFx port =
service.getWebServiceForJavaFxPort();
return port.getBookInfo(strID);
}
}
This application can be run also from
browsers, if the javafx applet will be a signed jar file, or maybe you change your
java.policy security file by adding the following lines to the
…jre7\lib\security\java.policy
grant {
permission java.security.AllPermission;
};
The running program is showed in the
following pictures:
