net.mograsim.logic.model/src/net/mograsim/logic/model/snippets/CodeSnippetSupplier.java

   1 package net.mograsim.logic.model.snippets;
   2
   3 import java.util.Collections;
   4 import java.util.HashMap;
   5 import java.util.Map;
   6
   7 public class CodeSnippetSupplier<C, S>
   8 {
   9         private final Map<String, String> standardSnippetIDClassNames = new HashMap<>();
  10         private final Map<String, String> standardSnippetIDClassNamesUnmodifiable = Collections.unmodifiableMap(standardSnippetIDClassNames);
  11         private final Map<String, SnippetDefinintion<C, ?, S>> snippetSuppliersForClassNames = new HashMap<>();
  12         private final SnippetDefinintion<C, ?, S> defaultSnippetSupplier;
  13
  14         public CodeSnippetSupplier(SnippetDefinintion<C, ?, S> defaultSnippetSupplier)
  15         {
  16                 this.defaultSnippetSupplier = defaultSnippetSupplier;
  17         }
  18
  19         public void addStandardSnippetID(String standardSnippetID, String associatedSnippetClassName)
  20         {
  21                 standardSnippetIDClassNames.put(standardSnippetID, associatedSnippetClassName);
  22         }
  23
  24         public Map<String, String> getStandardSnippetIDs()
  25         {
  26                 return standardSnippetIDClassNamesUnmodifiable;
  27         }
  28
  29         public void setSnippetSupplier(String id, SnippetDefinintion<C, ?, S> snippetSupplier)
  30         {
  31                 snippetSuppliersForClassNames.put(id, snippetSupplier);
  32         }
  33
  34         // TODO report errors
  35         public SnippetDefinintion<C, ?, S> getSnippetSupplier(String id)
  36         {
  37                 if (id != null)
  38                 {
  39                         String snippetClassName;
  40                         if (id.startsWith("class:"))
  41                                 snippetClassName = id.substring(6);
  42                         else
  43                                 snippetClassName = standardSnippetIDClassNames.get(id);
  44                         if (snippetClassName != null)
  45                         {
  46                                 tryLoadSnippetClass(snippetClassName);
  47                                 SnippetDefinintion<C, ?, S> snippetSupplier = snippetSuppliersForClassNames.get(snippetClassName);
  48                                 if (snippetSupplier != null)
  49                                         return snippetSupplier;
  50                         }
  51                         System.err.println("Couldn't load snippet " + id + "; using default");
  52                 }
  53                 if (defaultSnippetSupplier == null)
  54                         throw new IllegalArgumentException("No default snippet set");
  55                 return defaultSnippetSupplier;
  56         }
  57
  58         // static helpers
  59
  60         private static void tryLoadSnippetClass(String snippetClassName)
  61         {
  62                 tryInvokeStaticInitializer(snippetClassName, "Error getting snippet class: %s: %s\n");
  63         }
  64
  65         public static void tryInvokeStaticInitializer(String className, String errorMessageFormat)
  66         {
  67                 try
  68                 {
  69                         Class.forName(className, true, CodeSnippetSupplier.class.getClassLoader());
  70                 }
  71                 catch (ClassNotFoundException e)
  72                 {
  73                         System.err.printf(errorMessageFormat, className, "ClassNotFoundException thrown: " + e.getMessage());
  74                 }
  75         }
  76
  77 }