java sca 启航

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学走路,以下引自Apache上的一篇文章,共大家共勉:)~~~

The first thing you do is to create a folder on you disk into which you will download the TUSCANY distribution.



Next you download the latest release distribution. Launch your browser and enter one of the
following URL's.
Latest Release - http://cwiki.apache.org/TUSCANY/sca-java-releases.html
Download both the bin zip as well as the src zip to the folder that you created on your disk. Once you completed the download you should see the following on your disk.



Next you unzip the bin zip in place, you should see the following folder file structure on your disk after unzip is complete.


Setup Eclipse for Tuscany
Start Eclipse and create a User Library to contain the TUSCANY runtime jar's as well as their
depending jar's.

From the menu bar select Window and then Preferences... . The Preferences dialog will appear,
in its left navigation tree select Java, followed by Build Path, and followed by User Libraries.
Select the New... pushbutton on the right of the New Libraries dialog to create a new user library.



The user library created is empty, select the Add JARs... pushbutton on the right to add all the
jar's from your Tuscany installation lib folder. When completed all the jar's will appear under the
TUSCANY user library.



Since some of you maybe interested in debugging also the Tuscany runtime code we will attach
the Tuscany source to the Tuscany runtime jar in the following step. In the User Libraies dialog
scroll down until you see the Tuscany runtime jar and select its Source attachment.



Select the Edit... pushbutton on the right and in the Edit dialog use the External File... pushbutton
to the select the Tuscany src zip that we downloaded earlier.



Select OK to complete this and the Preferences dialog, and you are done with the Tuscany setup
for Eclipse.

Create your 1st Composite Service Application
The following shows the composition diagram for the composite service application you are about
to create.



The composite service application you will create is a composition of four services. The composed
service provided is that of an on-line store.
There is a Catalog service which you can ask for catalog items, and depending on its currency
code property configuration it will provide the item prices in USD or EUR. The Catalog service is not
doing the currency conversion itself it references a CurrencyConverter service to do that task. Then
there is the ShoppingCart service into which items chosen from the catalog can be added, it is
implemented as a REST service. The Catalog is bound using the JSONRPC binding, and the
ShoppingCart service is bound using the ATOM binding. Finally there is the Store user facing
service that provides the browser based user interface of the store. The Store service makes use of
the Catalog and ShoppingCart service using the JSONRPC, and ATOM binding respectively.

Create a Java Project
In this step you create a Java Project in Eclipse to hold the composite service application.
Click on the New Java Project button   in the toolbar to launch the project creation dialog.
Next you enter "store" as the Project name, and for Project Layout select Create separate
folders for sources and class files.




Hit the Next button, and on the following page go to the Libraries tab. Use the Add Library...
button on the right to add the TUSCANY user library to the project.




Hit the Finish button to complete the New Java Project dialog to create the "store" java project.





Construct Services
First you create two package folders into which later in this step you place service implementations.
Select the "store" project and click on the New Java Package button  in the toolbar to launch
the package creation dialog.

Next you enter "services" as the package Name, and press the Finish button to complete the
dialog.


Repeat the previous step to create another package named "ufservices". The store project now
should look as follows.



In the following you will place in the "services" package the regular services, and in the "ufservices"
package the user facing services of the composite service application you create.

Catalog
In this step you create the Catalog service interface and implementation.
Select the "services" package. Next you click on the dropdown arrow next to the New Java Class
button    and select the New Java Interface    option from the dropdown list. In the dialog
enter "Catalog" as the Name of the interface and select the Finish button to complete the dialog.
The Java editor will open on the new created Java interface. Replace the content of the editor by
copy-paste of the following Java interface code snippet.

package services;
import org.osoa.sca.annotations.Remotable;
@Remotable
public interface Catalog {
    String[] get();
}Select the "services" package again. Select the New Java Class button  . In the dialog enter
"CatalogImpl" as the Name of the class, add "Catalog" as the interface this class implements, and
then select Finish to complete the dialog.

The Java editor will open on the new created Java class. Replace the content of the editor by
copy-paste of the following Java class code snippet.

package services;
import java.util.ArrayList;
import java.util.List;
import org.osoa.sca.annotations.Init;
import org.osoa.sca.annotations.Property;
import org.osoa.sca.annotations.Reference;
public class CatalogImpl implements Catalog {
@Property
public String currencyCode = "USD";
@Reference
public CurrencyConverter currencyConverter;
private List catalog = new ArrayList();
@Init
public void init() {
  String currencySymbol = currencyConverter.getCurrencySymbol(currencyCode);
  catalog.add("Apple - " + currencySymbol +
  currencyConverter.getConversion("USD", currencyCode, 2.99f));
  catalog.add("Orange - " + currencySymbol +
  currencyConverter.getConversion("USD", currencyCode, 3.55f));
  catalog.add("Pear - " + currencySymbol +
  currencyConverter.getConversion("USD", currencyCode, 1.55f));
}
public String[] get() {
  String[] catalogArray = new String[catalog.size()];
  catalog.toArray(catalogArray);
  return catalogArray;
}
}After completing these steps the content of the "store" project will look as follows.


Note: CatalogImpl is red x'ed because it makes use of the CurrencyConverter interface that we
have not implemented yet.


CurrencyConverter
In this step you create the CurrencyConverter service interface and implementation.
You follow the same steps that you learned previously to create the interface and implementation.
First create a Java interface in the "services" package named "CurrencyConverter" and copy-paste
the following Java interface code snippet into it.
 

package services;
import org.osoa.sca.annotations.Remotable;
@Remotable
public interface CurrencyConverter {
public float getConversion(String fromCurrenycCode,
String toCurrencyCode, float amount);
public String getCurrencySymbol(String currencyCode);
}Next create a Java class in the "services" package named "CurrencyConverterImpl" and copy-paste
the following Java class code snippet into it.

package services;
public class CurrencyConverterImpl implements CurrencyConverter {
public float getConversion(String fromCurrencyCode,
  String toCurrencyCode, float amount) {
  if (toCurrencyCode.equals("USD"))
   return amount;
  else    if (toCurrencyCode.equals("EUR"))
    return amount*0.7256f;
  return 0;
}
public String getCurrencySymbol(String currencyCode) {
  if (currencyCode.equals("USD"))
   return "$";
  else
   if (currencyCode.equals("EUR"))
    return "?";
  return "?";
}
}After completing these steps the content of the "store" project will look as follows.



ShoppingCart
In this step you create the ShoppingCart service implementation.

You follow the same steps that you learned previously to create the implementation.

Create a Java class in the "services" package named "ShoppingCartImpl" and copy-paste the
following Java class code snippet into it.

package services;
import java.util.Date;
import java.util.HashMap;
import java.util.Map;
import java.util.UUID;
import org.apache.tuscany.sca.binding.feed.collection.Collection;
import org.apache.tuscany.sca.binding.feed.collection.NotFoundException;
import com.sun.syndication.feed.atom.Content;
import com.sun.syndication.feed.atom.Entry;
import com.sun.syndication.feed.atom.Feed;
import com.sun.syndication.feed.atom.Link;
public class ShoppingCartImpl implements Collection {
// needs to change to instance var once conversation scope works
private static Map cart = new HashMap();
public Feed getFeed() {
  Feed feed = new Feed();
  feed.setTitle("shopping cart");
  Content subtitle = new Content();
  subtitle.setValue("Total : " + getTotal());
  feed.setSubtitle(subtitle);
  feed.getEntries().addAll(cart.values());
  return feed;
}
public Entry get(String id) throws NotFoundException {
  return cart.get(id);
}
public Entry post(Entry entry) {
  String id = "cart-" + UUID.randomUUID().toString();
  entry.setId(id);
  Link link = new Link();
  link.setRel("edit");
  link.setHref("" + id);
  entry.getOtherLinks().add(link);
  link = new Link();
  link.setRel("alternate");
  link.setHref("" + id);
  entry.getAlternateLinks().add(link);
  entry.setCreated(new Date());
  cart.put(id, entry);
  return entry;
}
  public Entry put(String id, Entry entry) throws NotFoundException {
  entry.setUpdated(new Date());
  cart.put(id, entry);
  return entry;
}
public void delete(String id) throws NotFoundException {
  if (id.equals(""))
   cart.clear();
  else
   cart.remove(id);
}  private String getTotal() {
  float total = 0;
  String symbol = "";
  if (!cart.isEmpty()) {
   Entry entry = cart.values().iterator().next();
   String item = ((Content)entry.getContents().get(0)).getValue();
   symbol = item.substring(item.indexOf("-")+2, item.indexOf("-")+3);
  }
  for (Entry entry : cart.values()) {
   String item = ((Content)entry.getContents().get(0)).getValue();
   total += Float.valueOf(item.substring(item.indexOf("-")+3));
  }
  return symbol + String.valueOf(total);
}
}Note: Since the Tuscany conversational support is not ready yet the cart is realized through a hack.
The cart field is defined as static.

After completing these steps the content of the "store" project will look as follows.




Store
In this step you create the user facing Store service that will run in a Web browser and provide the
user interface to the other services you created.

Select the "ufservices" package. Right click to get the context menu, select New, and then File. In
the New File dialog enter "store.html" for the File name, and then select Finish to complete the
dialog.

The Text editor will open on the new created html file. Replace the content of the editor by copy-paste
of the following html snippet.

Store

Catalog

 

 

 

Your Shopping Cart

 

 

 

 

 
 
 
 
 

Next select the "ufservices" package again. Right click to get the context menu, select New, and
then File. In the New File dialog enter "binding-jsonrpc.js" for the File name, and then select
Finish to complete the dialog.

The Text editor will open on the new created javascript file. Replace the content of the editor by
copy-paste of the javascript snippet you find here:

http://svn.apache.org/repos/asf/incubator/tuscany/java/sca/modules/binding-jsonrpc/src/main/resources/org/apache/tuscany/sca/binding/jsonrpc/jsonrpc.js

Next select the "ufservices" package again. Right click to get the context menu, select New, and
then File. In the New File dialog enter "binding-atom.js" for the File name, and then select Finish
to complete the dialog.

The Text editor will open on the new created javascript file. Replace the content of the editor by
copy-paste of the following javascript snippet.

function AtomClient(uri) {
this.uri=uri;
this.get = function(id, responseFunction) {
  var xhr = this.createXMLHttpRequest();
  xhr.onreadystatechange = function() {
   if (xhr.readyState == 4) {
    if (xhr.status == 200) {
     if (responseFunction != null)
      responseFunction(xhr.responseXML);
    } else {
    alert("get - Error getting data from the server");
    }
   }
  }
  xhr.open("GET", uri + id, true);
  xhr.send(null);
}
this.post = function (entry, responseFunction) {
var xhr = this.createXMLHttpRequest();
xhr.onreadystatechange = function() {
  if (xhr.readyState == 4) {
   if (xhr.status == 201) {
    if (responseFunction != null)
     responseFunction(xhr.responseXML);
    } else {
     alert("post - Error getting data from the server");
    }
   }
  }
  xhr.open("POST", uri, true);
  xhr.setRequestHeader("Content-Type", "application/atom+xml");
  xhr.send(entry);
}
this.put = function (id, entry, responseFunction) {
  var xhr = this.createXMLHttpRequest();
  xhr.onreadystatechange = function() {
   if (xhr.readyState == 4) {
    if (xhr.status == 200) {
     if (responseFunction != null)
      responseFunction(xhr.responseXML);
    } else {
     alert("put - Error getting data from the server");
    }
   }
  }
  xhr.open("PUT", uri + id, true);
  xhr.setRequestHeader("Content-Type", "application/atom+xml");
  xhr.send(entry);
}
this.delete = function (id, responseFunction) {
  var xhr = this.createXMLHttpRequest();
  xhr.onreadystatechange = function() {
   if (xhr.readyState == 4) {
    if (xhr.status == 200) {
     if (responseFunction != null) responseFunction();
    } else {
     alert("delete - Error getting data from the server");
    }
   }
  }
  xhr.open("DELETE", uri + id, true);
  xhr.send(null);
}
this.createXMLHttpRequest = function () {
  try {return new XMLHttpRequest();} catch(e) {}
  try {return new ActiveXObject("Msxml2.XMLHTTP");} catch(e) {}
  try {return new ActiveXObject("Microsoft.XMLHTTP");} catch(e) {}
  alert("XML http request not supported");
  return null;
}
}Note: That we have to have the bindig-jsonrpc.js, and binding-atom.js local in our project is only
temporary, so this step will be removed in the future.

After completing these steps the content of the "store" project will look as follows.



Compose Services
Now that you have all the required service implementations you compose them together to provide
the store composite service. The composition is stored in a .composite file.

Select the "src" folder of the "store" project. Right click to get the context menu, select New, and
then File. In the New File dialog enter "store.composite" for the File name, and then select Finish
to complete the dialog.

The Text editor will open on the new created composite file. Replace the content of the editor by
copy-paste of the following composite snippet.


xmlns:t="http://tuscany.apache.org/xmlns/sca/1.0"
xmlns:s="http://store"
name="store">

 
 
  
 


 
  USD
 
  
 
 


 
 
  
 


 

After completing these steps the content of the "store" project will look as follows.




Launch Services
In this step you create the code to launch the Tuscany runtime with the new store composite
service you created.

Select the "store" project and click on the New Java Package button   in the toolbar to start the

package creation dialog. Use the dialog to create a new package named "launch".
Select the "launch" package. Select the New Java Class button   . In the dialog enter "Launch"
as the Name of the class, check the checkbox for creating a main method stub, and then select
Finish to complete the dialog.

The Java editor will open on the new created Java class. Replace the content of the editor by
copy-paste of the following Java class code snippet.

package launch;
import org.apache.tuscany.sca.host.embedded.SCADomain;
public class Launch {
public static void main(String[] args) throws Exception {
  System.out.println("Starting ...");
  SCADomain scaDomain = SCADomain.newInstance("store.composite");
  System.out.println("store.composite ready for big business !!!");
  System.out.println();
  System.in.read();
  scaDomain.close();
}
} After completing these steps the content of the "store" project will look as follows.


Congratulations you completed your 1st composite service applications, now its time to take it into
action.

Use Services
In this step you launch and use the store composite service application you created.

First select the "Launch" class in the "launch" package of your "store" project. Right click to get the
context menu, select Run As, and then Java application. The Tuscany runtime will start up adding
the store composition to its domain.

The Eclipse console will show the following messages.



Next Launch your Web browser and enter the following address:

http://localhost:8080/ufs/store.html

You get to the Store user facing service of the composite service application.



You can select items from the Catalog and add them to your Shopping Cart.

Note: When adding items for the first time you will be asked for userid and password by the
browser. Enter "admin" for both.



Since the ShoppingCart service is bound using the ATOM binding, you can also look at the
shopping card content in ATOM feed form by clicking on the feed icon . You get the browsers default rendering for ATOM feeds.



Use the browser back button to get back to the Store page.



And then you can Checkout to complete your order.



Explore the Samples from the Tuscany Distribution
The sample folder of the Tuscany distribution provides a rich set of samples ready for you to explore.



In Eclipse create a New Java Project, specify the project name, select Create project from
existing source, and specify the folder that contains the sample source.



Use Next to get to the next page in the New Java Project dialog. There go to the Libraries tab, use
the Add Library... pushbutton to add the JUnit library and the user library TUSCANY.



Finish the New Java Project dialog. You now have the sample project available in the Eclipse workbench.



For the calculator sample that we've chosen go to its CalculatorClient class and select Run As ->
Java Application. You will see the following output in the console.