src/java/org/ibex/xt/Prevalence.java

   1 package org.ibex.xt;
   2
   3 import java.io.*;
   4 import java.util.*;
   5 import javax.servlet.ServletContext;
   6
   7 import org.ibex.util.*;
   8 import org.ibex.js.*;
   9
  10 import org.prevayler.*;
  11 import org.prevayler.implementation.snapshot.*;
  12 //import com.thoughtworks.xstream.*; // FIXME find
  13
  14 public class Prevalence {
  15
  16     static final Hashtable prevaylers = new Hashtable();
  17
  18     public static void destroy(ServletContext cx, Prevayler prevayler) { try {
  19         prevaylers.remove(cx);
  20         prevayler.takeSnapshot();
  21         prevayler.close();
  22     } catch (Exception e) { e.printStackTrace(); } }
  23
  24     private static class SnapshotThread extends Thread {
  25         ServletContext cx;
  26         public SnapshotThread(ServletContext cx) { this.cx = cx; }
  27         public void run() {
  28             try {
  29                 Thread.sleep(10000);
  30                 Prevayler privatePrevayler = (Prevayler)prevaylers.get(cx);
  31                 if (privatePrevayler == null) return;
  32                 privatePrevayler.takeSnapshot();
  33             } catch (Exception e) {
  34                 e.printStackTrace();
  35             }
  36         }
  37     }
  38
  39     public static Prevayler getPrevayler(ServletContext cx) {
  40         try {
  41             Prevayler prevayler;
  42             synchronized(cx) {
  43                 prevayler = (Prevayler)prevaylers.get(cx);
  44                 if (prevayler == null) {
  45                     PrevaylerFactory pf = new PrevaylerFactory();
  46                     String base = cx.getRealPath("/") + "WEB-INF" + File.separatorChar + "prevalent";
  47                     System.err.println("prevayling to " + base);
  48                     pf.configurePrevalenceBase(base);
  49                     /*
  50                     XStreamSnapshotManager manager = new XStreamSnapshotManager(new JS(), base, null) {
  51                             protected XStream createXStream() {
  52                                 XStream xstream = new XStream();
  53                                 xstream.alias("js", JS.class);
  54                                 xstream.alias("jsdate", JSDate.class);
  55                                 return xstream;
  56                             }
  57                         };
  58                     System.err.println("configuring with " + manager);
  59                     pf.configureSnapshotManager(manager);
  60                     */
  61                     pf.configureSnapshotManager(new SnapshotManager(new JS(), base));
  62                     //pf.configureClassLoader(JSTransaction.class.getClassLoader());
  63                     prevayler = pf.create();
  64                     prevaylers.put(cx, prevayler);
  65                     new SnapshotThread(cx).start();
  66                 }
  67             }
  68             return prevayler;
  69         } catch (Exception e) { throw new RuntimeException(e); } }
  70
  71     public static class JSTransaction implements Transaction {
  72         public static final long serialVersionUid = 0xfb2aa281;
  73         private JS js;
  74         public JSTransaction(JS js) throws JSExn { this.js = js; }
  75         public void executeOn(Object o, Date now) {
  76             try {
  77                 JSScope scope = JS.getParentScope(js);
  78                 scope.put("prevalent", o);
  79                 scope.put("now", new JSDate(now.getTime()));
  80                 js.call(null, null, null, null, 0);
  81             } catch (Exception e) { throw new RuntimeException(e); }
  82         }
  83     }
  84
  85     public static class JSQuery implements Query {
  86         public static final long serialVersionUid = 0xfb2aa282;
  87         private JS js;
  88         private Object a;
  89         public JSQuery(JS js, Object a) { this.js = js; this.a = a; }
  90         public Object query(Object o, Date now) {
  91             try {
  92                 return js.call(o, a, new JSDate(now.getTime()), null, 3);
  93             } catch (Exception e) { throw new RuntimeException(e); }
  94         }
  95     }
  96 }