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

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