Multiple reader thread support for db client

[simantics/platform.git] / bundles / org.simantics.db.impl / src / org / simantics / db / impl / query / ValueQuery.java

diff --git a/bundles/org.simantics.db.impl/src/org/simantics/db/impl/query/ValueQuery.java b/bundles/org.simantics.db.impl/src/org/simantics/db/impl/query/ValueQuery.java
index d85595831851a5b87916d0edba978d2c67acef36..ad4017f9cff863c0a2bbe42a4fb9458a655e57f2 100644 (file)
--- a/bundles/org.simantics.db.impl/src/org/simantics/db/impl/query/ValueQuery.java
+++ b/bundles/org.simantics.db.impl/src/org/simantics/db/impl/query/ValueQuery.java
@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2007, 2010 Association for Decentralized Information Management
+ * Copyright (c) 2007, 2018 Association for Decentralized Information Management
  * in Industry THTH ry.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
@@ -11,152 +11,44 @@
  *******************************************************************************/
 package org.simantics.db.impl.query;
 
-import java.util.concurrent.Semaphore;
-
+import org.simantics.db.exception.DatabaseException;
 import org.simantics.db.impl.graph.ReadGraphImpl;
 import org.simantics.db.impl.procedure.InternalProcedure;
-import org.simantics.db.procedure.ListenerBase;
 
-final public class ValueQuery extends UnaryQuery<InternalProcedure<byte[]>> {
-    
-    private ValueQuery(final int resource) {
+public final class ValueQuery extends UnaryQueryP<byte[]> {
+
+    ValueQuery(int resource) {
         super(resource);
     }
-    
-    final static ValueQuery entry(final QueryProcessor provider, final int r) {
-        return (ValueQuery)provider.valueMap.get(r);
-    }
 
-    final static byte[] runner(final ReadGraphImpl graph, final int r, CacheEntry parent, final ListenerBase listener, final InternalProcedure<byte[]> procedure) {
-
-       QueryProcessor processor = graph.processor;
-       
-       ValueQuery entry = (ValueQuery)processor.valueMap.get(r); 
-        if(entry == null) {
-               
-               entry = new ValueQuery(r);
-               entry.setPending();
-               entry.clearResult(processor.querySupport);
-               entry.putEntry(processor);
-               
-               return (byte[])processor.performForEach(graph, entry, parent, listener, procedure);
-            
-        } else {
-               
-               return (byte[])processor.performForEach(graph, entry, parent, listener, procedure);
-            
-        }
-
-    }
-    
-    final public static byte[] queryEach(ReadGraphImpl graph, final int r, final CacheEntry parent, final ListenerBase listener, final InternalProcedure<byte[]> procedure) {
-        
-       assert(r != 0);
-       
-       if(graph.parent == null && listener == null) {
-               return ValueQuery.computeForEach(graph, r, null, procedure);
-        } else {
-               return runner(graph, r, parent, listener, procedure);
-        }
-         
+    @Override
+    public final void removeEntry(QueryProcessor provider) {
+        provider.cache.remove(this);
     }
 
-    final public static byte[] queryEach(ReadGraphImpl graph, final int r, final CacheEntry parent) {
-        
-        assert(r != 0);
-        
-        if(graph.parent == null) {
-            return ValueQuery.computeForEach(graph, r);
-        } else {
-            return runner(graph, r, parent, null, null);
-        }
-         
+    @Override
+    public void compute(ReadGraphImpl graph, InternalProcedure<byte[]> procedure) throws DatabaseException {
+        computeForEach(graph, id, this, procedure);
     }
-    
-       @Override
-       public UnaryQuery<InternalProcedure<byte[]>> getEntry(QueryProcessor provider) {
-        return provider.valueMap.get(id);
-       }
-       
-       @Override
-       public void putEntry(QueryProcessor provider) {
-        provider.valueMap.put(id, this);
-       }
-
-       @Override
-       final public void removeEntry(QueryProcessor provider) {
-               provider.valueMap.remove(id);
-       }
-       
-               
-       public static byte[] computeForEach(ReadGraphImpl graph, final int r, final ValueQuery entry, final InternalProcedure<byte[]> procedure) {
 
-               graph.ensureLoaded(r);
-               
-               byte[] value = graph.getValue(r);
-               if(entry != null) {
-                       entry.setResult(value);
-                       entry.setReady();
-               }
-               if(procedure != null) {
-                       procedure.execute(graph, value);
-               }
-               
-               return value;
-               
-       }
+    public static byte[] computeForEach(ReadGraphImpl graph, final int r, final ValueQuery entry, final InternalProcedure<byte[]> procedure_) throws DatabaseException {
 
-    public static byte[] computeForEach(ReadGraphImpl graph, final int r) {
+        InternalProcedure<byte[]> procedure = entry != null ? entry : procedure_;
 
         graph.ensureLoaded(r);
-        
-        return graph.getValue(r);
-        
-    }
-       
-       @Override
-       public Object computeForEach(ReadGraphImpl graph, final QueryProcessor queryProvider, final InternalProcedure<byte[]> procedure, final boolean store) {
-               return computeForEach(graph, id, this, procedure);
-    }
-    
-    @Override
-    public String toString() {
-       return "Value[" + id + "]";
-    }
 
-    @Override
-    public Object performFromCache(ReadGraphImpl graph, QueryProcessor queryProvider, InternalProcedure<byte[]> procedure) {
-       return computeForEach(graph, queryProvider, procedure, false);
-    }
-    
-    @Override
-    public void recompute(ReadGraphImpl graph, QueryProcessor provider) {
+        byte[] value = graph.getValue(r);
+        if(procedure != null) procedure.execute(graph, value);
 
-       final Semaphore s = new Semaphore(0);
-       
-        computeForEach(graph, provider, new InternalProcedure<byte[]>() {
+        if(entry != null && procedure_ != null) entry.performFromCache(graph, procedure_);
 
-            @Override
-            public void execute(ReadGraphImpl graph, byte[] result) {
-               s.release();
-            }
-                       
-                       @Override
-                       public void exception(ReadGraphImpl graph, Throwable t) {
-                               throw new Error("Error in recompute.", t);
-            }
+        return value;
 
-        }, true);
-        
-        while(!s.tryAcquire()) {
-               provider.resume(graph);
-        }
-        
     }
-    
+
     @Override
-    boolean isImmutable(ReadGraphImpl graph) {
-       return graph.processor.isImmutable(id);
-    }    
-    
+    public String toString() {
+        return "Value[" + id + "]";
+    }
+
 }