Implemented stub support for loading the latest journal on startup

djspiewak · Aug 12, 2011 · cd9a8be · cd9a8be
1 parent 1b186c0
commit cd9a8be
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Showing 2 changed files with 17 additions and 2 deletions.
diff --git a/src/main/scala/com/codecommit/dm/JournalComponent.scala b/src/main/scala/com/codecommit/dm/JournalComponent.scala
@@ -12,6 +12,8 @@ trait JournalComponent {
 
   def journal: Journal
   def journalSerializer: JournalSerializer
+
+  def readInitialJournalState: JournalRep
 
   trait Journal {
     def journal: JournalRep
@@ -38,7 +40,7 @@ trait MutableJournalComponent extends JournalComponent {
 
   override lazy val journal = new Journal {
     private val lock = new AnyRef
-    private var _journal: JournalRep = Vector()
+    private var _journal: JournalRep = readInitialJournalState
 
     def journal = _journal
 

diff --git a/src/main/scala/com/codecommit/dm/JournalPersistenceComponent.scala b/src/main/scala/com/codecommit/dm/JournalPersistenceComponent.scala
@@ -1,7 +1,7 @@
 package com.codecommit
 package dm
 
-import java.io.{OutputStream, FileOutputStream, BufferedOutputStream, IOException}
+import java.io._
 
 trait JournalPersistenceComponent extends JournalComponent {
   def journalPersister: JournalPersister
@@ -23,6 +23,19 @@ trait ThreadedJournalPersistenceComponent extends JournalPersistenceComponent {
   def JournalPersistenceDelay: Long
 
   def makeJournalFilename: String
+  def latestJournalFilename: String
+
+  override def readInitialJournalState = {
+    var is: InputStream = null         // gross!
+    try {
+      is = new BufferedInputStream(new FileInputStream(latestJournalFilename))
+      journalSerializer.read(is)
+    } finally {
+      if (is != null) {
+        is.close()
+      }
+    }
+  }
 
   override lazy val journalPersister = new JournalPersister with AsyncWorker {
     val Priority = 3