src/org/ibex/xt/Prevalence.java

   1 package org.ibex.xt;
   2 import org.ibex.js.*;
   3 import org.ibex.util.*;
   4 import org.ibex.io.*;
   5 import java.io.*;
   6 import java.net.*;
   7 import java.util.*;
   8 import javax.servlet.*;
   9 import javax.servlet.http.*;
  10 import com.thoughtworks.xstream.*;
  11 import org.prevayler.*;
  12 import org.prevayler.implementation.snapshot.*;
  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         JSScope newscope;
  75         Vec v;
  76         public JSTransaction(JS js) throws JSExn {
  77             newscope = new JSScope(null);
  78             this.js = JS.cloneWithNewParentScope(js, newscope);
  79             v = JS.getFormalArgs(this.js);
  80             for(int i=0; i<v.size(); i++) {
  81                 if ("prevalent".equals(v.elementAt(i))) continue;
  82                 newscope.put(v.elementAt(i), JS.getParentScope(js).get(v.elementAt(i)));
  83             }
  84         }
  85         public void executeOn(Object o, Date now) {
  86             try {
  87                 newscope.put("prevalent", o);
  88                 newscope.put("now", new JSDate(now.getTime()));
  89                 Object a = v.size() <= 0 ? null : newscope.get(v.elementAt(0));
  90                 Object b = v.size() <= 1 ? null : newscope.get(v.elementAt(1));
  91                 Object c = v.size() <= 2 ? null : newscope.get(v.elementAt(2));
  92                 Object[] rest = v.size() <= 3 ? null : new Object[v.size() - 3];
  93                 for(int i=3; i<v.size(); i++) rest[i-3] = v.elementAt(i);
  94                 js.call(a, b, c, rest, v.size());
  95             } catch (Exception e) { throw new RuntimeException(e); }
  96         }
  97     }
  98
  99     public static class JSQuery implements Query {
 100         public static final long serialVersionUid = 0xfb2aa282;
 101         private JS js;
 102         private Object a;
 103         public JSQuery(JS js, Object a) { this.js = JS.cloneWithNewParentScope(js, null); this.a = a; }
 104         public Object query(Object o, Date now) {
 105             try {
 106                 return js.call(o, a, new JSDate(now.getTime()), null, 3);
 107             } catch (Exception e) { throw new RuntimeException(e); }
 108         }
 109     }
 110 }