Merge branch 'feature/funcwrite'

[simantics/platform.git] / bundles / org.simantics.acorn / src / org / simantics / acorn / internal / AcornDatabase.java

diff --git a/bundles/org.simantics.acorn/src/org/simantics/acorn/internal/AcornDatabase.java b/bundles/org.simantics.acorn/src/org/simantics/acorn/internal/AcornDatabase.java
index 63c73dd634580e2c3f1add6c4d34b6d866ff926f..1025cc6a5dac0a2e6d5b940b1ad0d17ba971fa00 100644 (file)
--- a/bundles/org.simantics.acorn/src/org/simantics/acorn/internal/AcornDatabase.java
+++ b/bundles/org.simantics.acorn/src/org/simantics/acorn/internal/AcornDatabase.java
@@ -2,6 +2,8 @@ package org.simantics.acorn.internal;
 
 import java.io.File;
 import java.io.IOException;
+import java.io.RandomAccessFile;
+import java.nio.channels.FileLock;
 import java.nio.file.DirectoryStream;
 import java.nio.file.FileVisitOption;
 import java.nio.file.FileVisitResult;
@@ -17,7 +19,10 @@ import org.simantics.db.Database;
 import org.simantics.db.DatabaseUserAgent;
 import org.simantics.db.ServiceLocator;
 import org.simantics.db.common.utils.Logger;
+import org.simantics.db.exception.SDBException;
+import org.simantics.db.server.DatabaseStartException;
 import org.simantics.db.server.ProCoreException;
+import org.simantics.db.server.internal.InternalException;
 
 /**
  * @author Tuukka Lehtonen
@@ -25,9 +30,17 @@ import org.simantics.db.server.ProCoreException;
 public class AcornDatabase implements Database {
 
     private final Path folder;
+    
+    private GraphClientImpl2 currentClient;
 
     private DatabaseUserAgent userAgent;
 
+    private RandomAccessFile raLockFile;
+
+    private FileLock lock;
+
+    private boolean isRunning;
+
     public AcornDatabase(Path folder) {
         this.folder = folder;
     }
@@ -93,23 +106,49 @@ public class AcornDatabase implements Database {
 
     @Override
     public void deleteFiles() throws ProCoreException {
-        // TODO: somehow check that the acorn client is not active.
         deleteTree(folder);
     }
 
     @Override
     public void start() throws ProCoreException {
+        Path lockFile = folder.resolve("lock");
+        try {
+            if (!Files.exists(lockFile))
+                Files.createFile(lockFile);
+            
+            raLockFile = new RandomAccessFile(lockFile.toFile(), "rw");
+            lock = raLockFile.getChannel().tryLock();
+            if (lock == null) {
+                throw new ProCoreException("The database in folder " + folder.toAbsolutePath() + " is already in use!");
+            }
+            
+            isRunning = true;
+            
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
     }
 
     @Override
     public boolean isRunning() throws ProCoreException {
-        return true;
+        return isRunning;
     }
 
     @Override
     public boolean tryToStop() throws ProCoreException {
+        try {
+            lock.release();
+            raLockFile.close();
+            
+            Files.deleteIfExists(folder.resolve("lock"));
+            
+            isRunning = false;
+            
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
+        
         return true;
-//        throw new UnsupportedOperationException();
     }
 
     @Override
@@ -118,7 +157,7 @@ public class AcornDatabase implements Database {
 
     @Override
     public boolean isConnected() throws ProCoreException {
-        return true;
+        return isRunning;
     }
 
     @Override
@@ -156,22 +195,22 @@ public class AcornDatabase implements Database {
 
     @Override
     public void purgeDatabase() throws ProCoreException {
-        // TODO: implement
-        throw new UnsupportedOperationException();
+       if(currentClient == null) throw new IllegalStateException("No current session.");
+       currentClient.purgeDatabase();
     }
 
     @Override
     public long serverGetTailChangeSetId() throws ProCoreException {
-        // "We have it all"
-        // But after purging we don't so beware.
-        // TODO: beware for purge
-        return 1;
+       if(currentClient == null) throw new IllegalStateException("No current session.");
+       return currentClient.getTailChangeSetId();
     }
 
     @Override
     public Session newSession(ServiceLocator locator) throws ProCoreException {
         try {
-            return new GraphClientImpl2(this, folder, locator);
+               if(currentClient != null) throw new DatabaseStartException(folder.toFile(), "A session is already running. Only one session is supported.");
+               currentClient = new GraphClientImpl2(this, folder, locator); 
+            return currentClient;
         } catch (IOException e) {
             throw new ProCoreException(e);
         }