src/ibex/xt/Prevalence.java

   1 package ibex.xt;
   2
   3 import org.ibex.js.*;
   4 import ibex.util.*;
   5 //import org.ibex.io.*;
   6 import java.io.*;
   7 import java.net.*;
   8 import java.util.*;
   9 import javax.servlet.*;
  10 import javax.servlet.http.*;
  11 //import com.thoughtworks.xstream.*;
  12 import org.prevayler.*;
  13 import org.prevayler.implementation.snapshot.*;
  14
  15 public class Prevalence {
  16
  17     static final Hashtable prevaylers = new Hashtable();
  18
  19     public static void destroy(ServletContext cx, Prevayler prevayler) { try {
  20         prevaylers.remove(cx);
  21         prevayler.takeSnapshot();
  22         prevayler.close();
  23     } catch (Exception e) { e.printStackTrace(); } }
  24
  25     private static class SnapshotThread extends Thread {
  26         ServletContext cx;
  27         public SnapshotThread(ServletContext cx) { this.cx = cx; }
  28         public void run() {
  29             try {
  30                 Thread.sleep(10000);
  31                 Prevayler privatePrevayler = (Prevayler)prevaylers.get(cx);
  32                 if (privatePrevayler == null) return;
  33                 privatePrevayler.takeSnapshot();
  34             } catch (Exception e) {
  35                 e.printStackTrace();
  36             }
  37         }
  38     }
  39
  40     public static Prevayler getPrevayler(ServletContext cx) {
  41         try {
  42             Prevayler prevayler;
  43             synchronized(cx) {
  44                 prevayler = (Prevayler)prevaylers.get(cx);
  45                 if (prevayler == null) {
  46                     PrevaylerFactory pf = new PrevaylerFactory();
  47                     String base = cx.getRealPath("/") + "WEB-INF" + File.separatorChar + "prevalent";
  48                     System.err.println("prevayling to " + base);
  49                     pf.configurePrevalenceBase(base);
  50                     /*
  51                     XStreamSnapshotManager manager = new XStreamSnapshotManager(new JS(), base, null) {
  52                             protected XStream createXStream() {
  53                                 XStream xstream = new XStream();
  54                                 xstream.alias("js", JS.class);
  55                                 xstream.alias("jsdate", JSDate.class);
  56                                 return xstream;
  57                             }
  58                         };
  59                     System.err.println("configuring with " + manager);
  60                     pf.configureSnapshotManager(manager);
  61                     */
  62                     pf.configureSnapshotManager(new SnapshotManager(new JS(), base));
  63                     //pf.configureClassLoader(JSTransaction.class.getClassLoader());
  64                     prevayler = pf.create();
  65                     prevaylers.put(cx, prevayler);
  66                     new SnapshotThread(cx).start();
  67                 }
  68             }
  69             return prevayler;
  70         } catch (Exception e) { throw new RuntimeException(e); } }
  71
  72     public static class JSTransaction implements Transaction {
  73         public static final long serialVersionUid = 0xfb2aa281;
  74         private JS js;
  75         JSScope newscope;
  76         Vec v;
  77         public JSTransaction(JS js) throws JSExn {
  78             newscope = new JSScope(null);
  79             this.js = JS.cloneWithNewParentScope(js, newscope);
  80             v = JS.getFormalArgs(this.js);
  81             for(int i=0; i<v.size(); i++) {
  82                 if ("prevalent".equals(v.elementAt(i))) continue;
  83                 newscope.put(v.elementAt(i), JS.getParentScope(js).get(v.elementAt(i)));
  84             }
  85         }
  86         public void executeOn(Object o, Date now) {
  87             try {
  88                 newscope.put("prevalent", o);
  89                 newscope.put("now", new JSDate(now.getTime()));
  90                 Object a = v.size() <= 0 ? null : newscope.get(v.elementAt(0));
  91                 Object b = v.size() <= 1 ? null : newscope.get(v.elementAt(1));
  92                 Object c = v.size() <= 2 ? null : newscope.get(v.elementAt(2));
  93                 Object[] rest = v.size() <= 3 ? null : new Object[v.size() - 3];
  94                 for(int i=3; i<v.size(); i++) rest[i-3] = v.elementAt(i);
  95                 js.call(a, b, c, rest, v.size());
  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 = JS.cloneWithNewParentScope(js, null); this.a = a; }
 105         public Object query(Object o, Date now) {
 106             try {
 107                 return js.call(o, a, new JSDate(now.getTime()), null, 3);
 108             } catch (Exception e) { throw new RuntimeException(e); }
 109         }
 110     }
 111 }