bundles/org.simantics.scl.commands/src/org/simantics/scl/commands/internal/StringConverterFactory.java

   1 package org.simantics.scl.commands.internal;
   2
   3 import java.util.concurrent.ConcurrentHashMap;
   4
   5 import org.simantics.db.Resource;
   6 import org.simantics.scl.compiler.environment.specification.EnvironmentSpecification;
   7 import org.simantics.scl.compiler.module.repository.ImportFailureException;
   8 import org.simantics.scl.compiler.runtime.RuntimeEnvironment;
   9 import org.simantics.scl.compiler.top.ExpressionEvaluator;
  10 import org.simantics.scl.compiler.top.SCLExpressionCompilationException;
  11 import org.simantics.scl.compiler.top.ValueNotFound;
  12 import org.simantics.scl.compiler.types.Type;
  13 import org.simantics.scl.compiler.types.Types;
  14 import org.simantics.scl.osgi.SCLOsgi;
  15 import org.simantics.scl.runtime.function.Function2;
  16
  17 @SuppressWarnings({"rawtypes", "unchecked"})
  18 public class StringConverterFactory {
  19     private static final ConcurrentHashMap<Type, Function2> CONVERTER_CACHE =
  20             new ConcurrentHashMap<Type, Function2>();
  21     private static RuntimeEnvironment environment;
  22
  23     private static final Type ALLOWED_EFFECT = Types.union(new Type[] {Types.READ_GRAPH, Types.PROC});
  24
  25     /**
  26      * Creates a string converter for given type.
  27      * @throws ValueNotFound
  28      */
  29     public static Function2<Resource,Object,String> stringConverterFor(Type type) throws SCLExpressionCompilationException, ImportFailureException {
  30         Function2 converter = CONVERTER_CACHE.get(type);
  31         if(converter == null) {
  32             if(environment == null) {
  33                 // no need to synchronize access to environment
  34                 environment = SCLOsgi.MODULE_REPOSITORY.createRuntimeEnvironment(
  35                         EnvironmentSpecification.of(
  36                                 "Simantics/GShow", "",
  37                                 "Simantics/RouteGraph", "",
  38                                 "Prelude", ""
  39                                 ), StringConverterFactory.class.getClassLoader()
  40                         );
  41             }
  42             converter = (Function2)new ExpressionEvaluator(environment, "\\ctx r -> gshow ctx (Par 0 r)")
  43             .expectedType(Types.function(Types.RESOURCE, Types.functionE(type, ALLOWED_EFFECT, Types.STRING)))
  44             .eval();
  45             CONVERTER_CACHE.put(type, converter);
  46         }
  47         return converter;
  48     }
  49 }