bundles/org.simantics.mapping/src/org/simantics/mapping/rule/instructions/IfRuleInstruction.java

   1 /*******************************************************************************\r
   2  * Copyright (c) 2007, 2010 Association for Decentralized Information Management\r
   3  * in Industry THTH ry.\r
   4  * All rights reserved. This program and the accompanying materials\r
   5  * are made available under the terms of the Eclipse Public License v1.0\r
   6  * which accompanies this distribution, and is available at\r
   7  * http://www.eclipse.org/legal/epl-v10.html\r
   8  *\r
   9  * Contributors:\r
  10  *     VTT Technical Research Centre of Finland - initial API and implementation\r
  11  *******************************************************************************/\r
  12 package org.simantics.mapping.rule.instructions;\r
  13 \r
  14 import gnu.trove.map.hash.TIntIntHashMap;\r
  15 import gnu.trove.set.hash.TIntHashSet;\r
  16 \r
  17 import org.simantics.db.ReadGraph;\r
  18 import org.simantics.db.WriteGraph;\r
  19 import org.simantics.db.exception.DatabaseException;\r
  20 import org.simantics.layer0.utils.triggers.IModification;\r
  21 import org.simantics.mapping.constraint.instructions.IInstruction;\r
  22 \r
  23 public class IfRuleInstruction implements IRuleInstruction {\r
  24         IInstruction condition;\r
  25         IRuleInstruction rule;\r
  26         IRuleInstruction elseRule;      \r
  27         \r
  28         public IfRuleInstruction(IInstruction condition, IRuleInstruction rule, IRuleInstruction elseRule) {\r
  29                 this.condition = condition;\r
  30                 this.rule = rule;\r
  31                 this.elseRule = elseRule;\r
  32         }\r
  33         \r
  34         public IfRuleInstruction(IInstruction condition, IRuleInstruction rule) {\r
  35                 this(condition, rule, null);\r
  36         }       \r
  37         \r
  38         @Override\r
  39         public IModification execute(ReadGraph g, final Object[] bindings) throws DatabaseException {\r
  40                 if(DEBUG)\r
  41                         System.out.println("IfRuleInstruction: condition");\r
  42                 Object cont = condition.query(g, bindings);\r
  43                 if(cont == IInstruction.FAILURE) {\r
  44                         if(DEBUG)\r
  45                           System.out.println("IfRuleInstruction: else");\r
  46                         if(elseRule!=null)\r
  47                                 return elseRule.execute(g, bindings);\r
  48                         else\r
  49                                 return null;\r
  50                 }\r
  51                 do {\r
  52                         if(DEBUG)\r
  53                                 System.out.println("IfRuleInstruction: modification");\r
  54                         final IModification modi = rule.execute(g, bindings);\r
  55                         if(modi != null) {\r
  56                                 if(cont==null)\r
  57                                         return modi;\r
  58                                 final Object curCont = condition.next(g, bindings, cont);\r
  59                                 if(curCont==IInstruction.FAILURE)\r
  60                                         return modi;\r
  61                                 return new IModification() {\r
  62                                         @Override\r
  63                                         public void perform(WriteGraph g) throws DatabaseException {\r
  64                                                 modi.perform(g);\r
  65                                                 Object cont = curCont;\r
  66                                                 do {\r
  67                                                         rule.doExecute(g, bindings);\r
  68                                                         if(cont==null)\r
  69                                                                 break;\r
  70                                                         cont = condition.next(g, bindings, cont);\r
  71                                                 } while(cont != IInstruction.FAILURE);\r
  72                                         }                               \r
  73                                 };      \r
  74                         }\r
  75                         if(cont==null)\r
  76                                 break;\r
  77                         cont = condition.next(g, bindings, cont);\r
  78                 } while(cont != IInstruction.FAILURE);\r
  79                 return null;\r
  80         }\r
  81         \r
  82         @Override\r
  83         public void doExecute(WriteGraph g, Object[] bindings) throws DatabaseException {\r
  84                 Object cont = condition.query(g, bindings);\r
  85                 if(cont == IInstruction.FAILURE) {\r
  86                         if(elseRule!=null) \r
  87                                 elseRule.doExecute(g, bindings);\r
  88                         return;\r
  89                 }\r
  90                 do {\r
  91                         rule.doExecute(g, bindings);\r
  92                         if(cont==null)\r
  93                                 break;\r
  94                         cont = condition.next(g, bindings, cont);\r
  95                 } while(cont != IInstruction.FAILURE);\r
  96         }\r
  97         \r
  98         @Override\r
  99         public void collectVariables(TIntHashSet reads, TIntHashSet writes) {\r
 100                 condition.collectVariables(reads, writes);\r
 101                 rule.collectVariables(reads, writes);\r
 102                 if(elseRule != null)\r
 103                         elseRule.collectVariables(reads, writes);\r
 104         }\r
 105 \r
 106         @Override\r
 107         public void mapVariables(TIntIntHashMap map) {\r
 108                 condition.mapVariables(map);\r
 109                 rule.mapVariables(map);\r
 110                 if(elseRule != null)\r
 111                         elseRule.mapVariables(map);\r
 112         }\r
 113 \r
 114         @Override\r
 115         public void toString(StringBuilder b, int indent) {             \r
 116                 b.append("if   ");\r
 117                 condition.toString(b, indent+1);\r
 118                 \r
 119                 b.append('\n');         \r
 120                 for(int i=0;i<indent;++i)\r
 121                         b.append(INDENTATION);\r
 122                 b.append("then ");\r
 123                 rule.toString(b, indent+1);             \r
 124                 \r
 125                 if(elseRule != null) {\r
 126                         b.append('\n');\r
 127                         for(int i=0;i<indent;++i)\r
 128                                 b.append(INDENTATION);\r
 129                         b.append("else ");\r
 130                         elseRule.toString(b, indent+1);\r
 131                 }\r
 132         }\r
 133 }\r