src/org/ibex/xt/Prevalence.java

   1 // Copyright 2000-2005 the Contributors, as shown in the revision logs.
   2 // Licensed under the Apache Public Source License 2.0 ("the License").
   3 // You may not use this file except in compliance with the License.
   4
   5 package org.ibex.xt;
   6 import org.ibex.js.*;
   7 import org.ibex.util.*;
   8 import org.ibex.io.*;
   9 import java.io.*;
  10 import java.net.*;
  11 import java.util.*;
  12 import javax.servlet.*;
  13 import javax.servlet.http.*;
  14 import com.thoughtworks.xstream.*;
  15 import org.prevayler.*;
  16 import org.prevayler.implementation.snapshot.*;
  17
  18 public class Prevalence {
  19
  20     static final Hashtable prevaylers = new Hashtable();
  21
  22     public static void destroy(ServletContext cx, Prevayler prevayler) { try {
  23         prevaylers.remove(cx);
  24         prevayler.takeSnapshot();
  25         prevayler.close();
  26     } catch (Exception e) { e.printStackTrace(); } }
  27
  28     private static class SnapshotThread extends Thread {
  29         ServletContext cx;
  30         public SnapshotThread(ServletContext cx) { this.cx = cx; }
  31         public void run() {
  32             try {
  33                 Thread.sleep(10000);
  34                 Prevayler privatePrevayler = (Prevayler)prevaylers.get(cx);
  35                 if (privatePrevayler == null) return;
  36                 privatePrevayler.takeSnapshot();
  37             } catch (Exception e) {
  38                 e.printStackTrace();
  39             }
  40         }
  41     }
  42
  43     public static Prevayler getPrevayler(ServletContext cx) {
  44         try {
  45             Prevayler prevayler;
  46             synchronized(cx) {
  47                 prevayler = (Prevayler)prevaylers.get(cx);
  48                 if (prevayler == null) {
  49                     PrevaylerFactory pf = new PrevaylerFactory();
  50                     String base = cx.getRealPath("/") + "WEB-INF" + File.separatorChar + "prevalent";
  51                     System.err.println("prevayling to " + base);
  52                     pf.configurePrevalenceBase(base);
  53                     /*
  54                     XmlSnapshotManager manager = new XmlSnapshotManager(new JS(), base, null); {
  55                             protected XStream createXStream() {
  56                                 XStream xstream = new XStream();
  57                                 xstream.alias("js", JS.class);
  58                                 xstream.alias("jsdate", JSDate.class);
  59                                 return xstream;
  60                             }
  61                             };
  62                     System.err.println("configuring with " + manager);
  63                     pf.configureSnapshotManager(manager);
  64                     */
  65                     pf.configureSnapshotManager(new SnapshotManager(new JS.Obj(), base));
  66                     //pf.configureClassLoader(JSTransaction.class.getClassLoader());
  67                     prevayler = pf.create();
  68                     prevaylers.put(cx, prevayler);
  69                     new SnapshotThread(cx).start();
  70                 }
  71             }
  72             return prevayler;
  73         } catch (Exception e) { throw new RuntimeException(e); } }
  74
  75     public static class JSTransaction implements Transaction {
  76         public static final long serialVersionUid = 0xfb2aa281;
  77         private JS js;
  78         Template.Scope newscope;
  79         String[] v;
  80         public JSTransaction(JS js) throws JSExn {
  81             newscope = new Template.Scope(null);
  82             this.js = JSU.cloneWithNewGlobalScope(js, newscope);
  83             v = this.js.getFormalArgs();
  84             for(int i=0; i<v.length; i++) {
  85                 if (JSU.S("prevalent").equals(v[i])) continue;
  86                 newscope.put(JSU.S(v[i]), js.get(JSU.S(v[i])));
  87             }
  88         }
  89         public void executeOn(Object o, Date now) {
  90             try {
  91                 newscope.put(JSU.S("prevalent"), (JS)o);
  92                 newscope.put(JSU.S("now"), new JSDate(now.getTime()));
  93                 JS[] args = new JS[v.length];
  94                 for(int i=0; i<v.length; i++) args[i] = JSU.S(v[i]);
  95                 js.call(null, args);
  96             } catch (Exception e) { throw new RuntimeException(e); }
  97         }
  98     }
  99
 100     public static class JSQuery implements Query {
 101         public static final long serialVersionUid = 0xfb2aa282;
 102         private JS js;
 103         private Object a;
 104         public JSQuery(JS js, Object a) { this.js = JSU.cloneWithNewGlobalScope(js, null); this.a = a; }
 105         public Object query(Object o, Date now) {
 106             try {
 107                 return js.call(null, new JS[] { (JS)o, (JS)a, new JSDate(now.getTime()) });
 108             } catch (Exception e) { throw new RuntimeException(e); }
 109         }
 110     }
 111 }