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/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package sample;
import java.io.IOException;
import java.net.URL;
import java.util.Date;
import java.util.Stack;
import org.oasisopen.sca.annotation.EagerInit;
import org.oasisopen.sca.annotation.Init;
import org.oasisopen.sca.annotation.Reference;
import org.oasisopen.sca.annotation.Scope;
import org.oasisopen.sca.annotation.Service;
import com.google.appengine.api.datastore.DatastoreService;
import com.google.appengine.api.datastore.Entity;
import com.google.appengine.api.datastore.EntityNotFoundException;
import com.google.appengine.api.datastore.Key;
import com.google.appengine.api.datastore.KeyFactory;
import com.google.appengine.api.datastore.Transaction;
import com.google.appengine.api.memcache.Expiration;
import com.google.appengine.api.memcache.MemcacheService;
import com.google.appengine.api.urlfetch.HTTPResponse;
import com.google.appengine.api.urlfetch.URLFetchService;
import com.google.appengine.api.users.User;
import com.google.appengine.api.users.UserService;
@EagerInit
@Scope("COMPOSITE")
@Service(HelloworldService.class)
public class HelloworldServiceImpl implements HelloworldService {
@Reference
protected UserService userService;
@Reference
protected URLFetchService fetchService;
@Reference
protected MemcacheService memcacheService;
@Reference
protected DatastoreService datastoreService;
public String sayHello(String name) {
User user = userService.getCurrentUser();
String id = (user == null) ? "" : user.getUserId();
Stack<String> stack = cacheHistory(name);
Long count = countInStore();
String content = fetch();
return "[" + id
+ "] Hello "
+ name
+ "<hr><h2>Content from Tuscany Web Site via URLFetch</h2><p>"
+ content
+ "<p>"
+ toHTML(stack)
+ "</p><b>Counter from DataStore: "
+ count
+ "</b><p>";
}
private String fetch() {
String content = "";
try {
HTTPResponse response = fetchService.fetch(new URL("http://tuscany.apache.org"));
content = new String(response.getContent(), 0, 1024);
content = content.replace("<", "<");
content = content.replace(">", ">");
content = content.replace("\"", """);
} catch (IOException e) {
e.printStackTrace();
}
return content;
}
private Long countInStore() {
Transaction tx = datastoreService.beginTransaction();
Entity entity = null;
Key key = KeyFactory.createKey("HitCounter", "countter");
try {
entity = datastoreService.get(tx, key);
} catch (EntityNotFoundException e1) {
entity = new Entity(key);
entity.setProperty("counter", new Long(0));
}
Long count = (Long)entity.getProperty("counter");
count = new Long(count.longValue() + 1);
entity.setProperty("counter", count);
datastoreService.put(tx, entity);
tx.commit();
return count;
}
private Stack<String> cacheHistory(String name) {
Stack<String> stack = (Stack<String>)memcacheService.get("history");
if (stack == null) {
stack = new Stack<String>();
}
stack.push(new Date().toString() + ": " + name);
memcacheService.put("history", stack, Expiration.byDeltaSeconds(60));
return stack;
}
private String toHTML(Stack<String> stack) {
StringBuffer html = new StringBuffer("<h2>History from Memcache (expired in 1 minute)</h2><hr><ul>");
for (String item : stack) {
html.append("<li>").append(item).append("</li>");
}
html.append("</ul><hr>");
return html.toString();
}
@Init
public void init() {
System.out.println("Starting...");
}
}
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