Small improvement for plan save-load API

plugins/org.jkiss.dbeaver.ext.oracle/src/org/jkiss/dbeaver/ext/oracle/model/plan/OraclePlanNode.java

@@ -21,7 +21,6 @@ import org.jkiss.dbeaver.ext.oracle.model.OracleDataSource;
 import org.jkiss.dbeaver.ext.oracle.model.OracleObjectType;
 import org.jkiss.dbeaver.ext.oracle.model.OracleTablePhysical;
 import org.jkiss.dbeaver.model.exec.plan.DBCPlanCostNode;
-import org.jkiss.dbeaver.model.exec.plan.DBCPlanNodeComplex;
 import org.jkiss.dbeaver.model.impl.jdbc.JDBCUtils;
 import org.jkiss.dbeaver.model.impl.plan.AbstractExecutionPlanNode;
 import org.jkiss.dbeaver.model.meta.Property;
@@ -41,7 +40,7 @@ import java.util.Map;
 /**
  * Oracle execution plan node
  */
-public class OraclePlanNode extends AbstractExecutionPlanNode implements DBCPlanCostNode, DBCPlanNodeComplex<OraclePlanNode> {
+public class OraclePlanNode extends AbstractExecutionPlanNode implements DBCPlanCostNode {
 
     public final static String CAT_DETAILS = "Details";
 
@@ -84,7 +83,7 @@ public class OraclePlanNode extends AbstractExecutionPlanNode implements DBCPlan
     private String otherXml;
 
     private OraclePlanNode parent;
-    protected List<OraclePlanNode> nested;
+    protected final List<OraclePlanNode> nested = new ArrayList<>();
 
     private String aGetString(Map<String,String> attributes,String name) {
         return attributes.containsKey(name) ? attributes.get(name).toString() : "";
@@ -224,10 +223,7 @@ public class OraclePlanNode extends AbstractExecutionPlanNode implements DBCPlan
     }
 
     private void addChild(OraclePlanNode node) {
-        if (this.nested == null) {
-            createNested();
-        }
-        this.nested.add(node);
+         this.nested.add(node);
     }
 
     @Override
@@ -513,10 +509,5 @@ public class OraclePlanNode extends AbstractExecutionPlanNode implements DBCPlan
         }
     }
 
-    @Override
-    public void createNested() {
-        this.nested = new ArrayList<>();
-       
-    }
 
 }

plugins/org.jkiss.dbeaver.ext.postgresql/src/org/jkiss/dbeaver/ext/postgresql/model/plan/PostgrePlanNodeBase.java

@@ -53,7 +53,7 @@ public abstract class PostgrePlanNodeBase<NODE extends PostgrePlanNodeBase> exte
 
     private PostgreDataSource dataSource;
     protected NODE parent;
-    protected List<NODE> nested;
+    protected final List<NODE> nested = new ArrayList<>();
 
     protected String nodeType;
     private String entity;

plugins/org.jkiss.dbeaver.ext.postgresql/src/org/jkiss/dbeaver/ext/postgresql/model/plan/PostgrePlanNodeXML.java

@@ -21,7 +21,6 @@ import org.jkiss.utils.xml.XMLUtils;
 import org.w3c.dom.Element;
 import org.w3c.dom.Node;
 
-import java.util.ArrayList;
 import java.util.LinkedHashMap;
 import java.util.Map;
 
@@ -44,9 +43,6 @@ public class PostgrePlanNodeXML extends PostgrePlanNodeBase<PostgrePlanNodeXML>
         Element nestedPlansElement = XMLUtils.getChildElement(element, "Plans");
         if (nestedPlansElement != null) {
             for (Element planElement : XMLUtils.getChildElementList(nestedPlansElement, "Plan")) {
-                if (nested == null) {
-                    nested = new ArrayList<>();
-                }
                 nested.add(new PostgrePlanNodeXML(dataSource, null, planElement));
             }
         }

plugins/org.jkiss.dbeaver.ext.postgresql/src/org/jkiss/dbeaver/ext/postgresql/model/plan/PostgresPlanNodeExternal.java

@@ -25,14 +25,13 @@ import java.util.Map;
 import java.util.Map.Entry;
 
 import org.jkiss.dbeaver.ext.postgresql.model.PostgreDataSource;
-import org.jkiss.dbeaver.model.exec.plan.DBCPlanNodeComplex;
 import org.jkiss.dbeaver.model.impl.plan.AbstractExecutionPlanSerializer;
 
 import com.google.gson.JsonArray;
 import com.google.gson.JsonElement;
 import com.google.gson.JsonObject;
 
-public class PostgresPlanNodeExternal  extends PostgrePlanNodeBase<PostgresPlanNodeExternal> implements DBCPlanNodeComplex<PostgresPlanNodeExternal> {
+public class PostgresPlanNodeExternal  extends PostgrePlanNodeBase<PostgresPlanNodeExternal> {
 
     private PostgresPlanNodeExternal(PostgreDataSource dataSource, PostgresPlanNodeExternal parent) {
         super(dataSource, parent);
@@ -58,14 +57,6 @@ public class PostgresPlanNodeExternal  extends PostgrePlanNodeBase<PostgresPlanN
         setAttributes(attributes);
     }
 
-    @Override
-    public List<PostgresPlanNodeExternal> getNested() {
-        return nested;
-    }
 
-    @Override
-    public void createNested() {
-        nested = new ArrayList<>();
-        
-    }
+
 }

plugins/org.jkiss.dbeaver.model/src/org/jkiss/dbeaver/model/exec/plan/DBCPlanNodeComplex.java

-/*
- * DBeaver - Universal Database Manager
- * Copyright (C) 2010-2019 Serge Rider (serge@jkiss.org)
- * Copyright (C) 2019 Andrew Khitrin (ahitrin@gmail.com)
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package org.jkiss.dbeaver.model.exec.plan;
-
-import java.util.Collection;
-
-
-public interface DBCPlanNodeComplex <NODE extends DBCPlanNode> {
-   Collection<NODE> getNested();
-   void createNested();
-}

plugins/org.jkiss.dbeaver.model/src/org/jkiss/dbeaver/model/impl/plan/ExecutionPlanDeserializer.java

 package org.jkiss.dbeaver.model.impl.plan;
 
 import java.util.ArrayList;
+import java.util.Collection;
 import java.util.List;
 
 import org.jkiss.dbeaver.model.DBPDataSource;
 import org.jkiss.dbeaver.model.exec.plan.DBCPlanNode;
-import org.jkiss.dbeaver.model.exec.plan.DBCPlanNodeComplex;
 import org.jkiss.dbeaver.model.exec.plan.DBCQueryPlannerDeSerialInfo;
 
 import com.google.gson.JsonArray;
@@ -27,18 +27,12 @@ public class ExecutionPlanDeserializer<NODE extends DBCPlanNode> {
         NODE node = info.createNode(dataSource, nodeObject, parent);
         JsonArray childs = nodeObject.getAsJsonArray(AbstractExecutionPlanSerializer.PROP_CHILD);
         
-        if (node instanceof DBCPlanNodeComplex<?>) {
-            DBCPlanNodeComplex<NODE> n = (DBCPlanNodeComplex<NODE>) node;
-            if (n.getNested() == null) {
-                n.createNested();
-            }
-            if (childs != null) {
-                childs.forEach((e) -> {
-                    n.getNested().add(loadNode(dataSource, e.getAsJsonObject(), node, info));
-                });
-
-            }
+        if (childs != null) {
+            childs.forEach((e) -> {
+                ((Collection<NODE>) node.getNested()).add(loadNode(dataSource, e.getAsJsonObject(), node, info));
+            });
         }
+        
         return node;
     }