bundles/org.simantics.databoard/src/org/simantics/databoard/binding/factory/TypeBindingFactory.java

   1 package org.simantics.databoard.binding.factory;\r
   2 \r
   3 import java.util.HashMap;\r
   4 import java.util.Map;\r
   5 \r
   6 import org.simantics.databoard.binding.Binding;\r
   7 import org.simantics.databoard.binding.error.BindingConstructionException;\r
   8 import org.simantics.databoard.binding.error.RuntimeBindingConstructionException;\r
   9 import org.simantics.databoard.type.Datatype;\r
  10 \r
  11 /**\r
  12  * Type Factory constructs data types from reflection requests.\r
  13  * Successfully constructed types are placed in the repository that was given \r
  14  * at construction time.\r
  15  *  \r
  16  * @author Toni Kalajainen\r
  17  */\r
  18 public abstract class TypeBindingFactory implements BindingScheme {\r
  19         \r
  20         /**\r
  21          * Map of failed constructions. \r
  22          */\r
  23         protected Map<Datatype, BindingConstructionException> failures = new HashMap<Datatype, BindingConstructionException>();\r
  24         \r
  25         /**\r
  26          * Map that contains in incomplete constructions.\r
  27          */\r
  28         protected Map<Datatype, Binding> inprogress = new HashMap<Datatype, Binding>();\r
  29         \r
  30         /**\r
  31          * Repository where successful constructions are placed. \r
  32          */\r
  33         protected Map<Datatype, Binding> repository;    \r
  34         \r
  35         /**\r
  36          * Create a scheme factory. \r
  37          */\r
  38         public TypeBindingFactory() {\r
  39                 this.repository = new HashMap<Datatype, Binding>();\r
  40         }\r
  41         \r
  42         /**\r
  43          * Create scheme factory that appends constructed bindings to the user given\r
  44          * repository  \r
  45          * \r
  46          * @param repository repository where bindings are placed\r
  47          */\r
  48         public TypeBindingFactory(Map<Datatype, Binding> repository) {\r
  49                 this.repository = repository;\r
  50         }\r
  51         \r
  52         /**\r
  53          * Get Repository\r
  54          * @return binding repository\r
  55          */\r
  56         public Map<Datatype, Binding> getRepository() {\r
  57                 return repository;\r
  58         }\r
  59 \r
  60         /**\r
  61          * Constructs a binding to comply to datatype request.\r
  62          * This is the method sub-classes implement. \r
  63          * The implementation should use the inprogress -map for construction of \r
  64          * bindings that have component types.\r
  65          * \r
  66          *  e.g. \r
  67          *   inprogress.put(request, notCompletelyConstructedBinding);\r
  68          *   Binding componentBinding = construct( componentRequest );\r
  69          *   notCompletelyConstructedBinding.setChild( componentBinding );\r
  70          *   inprogress.remove(request);\r
  71          *   \r
  72          * try-finally is not needed.\r
  73          * \r
  74          * @param request\r
  75          * @return\r
  76          * @throws BindingConstructionException\r
  77          */\r
  78         protected abstract Binding doConstruct(Datatype request) throws BindingConstructionException;\r
  79         \r
  80         public Binding construct(Datatype request) throws BindingConstructionException\r
  81         {\r
  82                 if (failures.containsKey(request)) throw failures.get(request);\r
  83                 if (inprogress.containsKey(request)) return inprogress.get(request);\r
  84                 if (repository.containsKey(request)) return repository.get(request);\r
  85                 \r
  86                 // Start construction\r
  87                 try {                   \r
  88                         Binding binding = doConstruct(request);\r
  89                         repository.put(request, binding);\r
  90                         return binding;\r
  91                 } catch (BindingConstructionException e) {\r
  92                         inprogress.remove( request );\r
  93                         failures.put(request, e);\r
  94                         throw e;\r
  95                 }\r
  96         }\r
  97 \r
  98         @Override\r
  99         public Binding getBinding(Datatype type)\r
 100                         throws BindingConstructionException {           \r
 101                 return construct(type);\r
 102         }\r
 103         \r
 104         @Override\r
 105         public Binding getBindingUnchecked(Datatype type)\r
 106                         throws RuntimeBindingConstructionException {\r
 107                 try {\r
 108                         return construct(type);\r
 109                 } catch (BindingConstructionException e) {\r
 110                         throw new RuntimeBindingConstructionException(e);\r
 111                 }\r
 112         }       \r
 113         \r
 114 \r
 115 }\r