java/java-impl/src/com/intellij/codeInsight/template/macro/ExpectedTypeMacro.java

   1 /*
   2  * Copyright 2000-2009 JetBrains s.r.o.
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at
   7  *
   8  * http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16 package com.intellij.codeInsight.template.macro;
  17
  18 import com.intellij.codeInsight.CodeInsightBundle;
  19 import com.intellij.codeInsight.ExpectedTypeInfo;
  20 import com.intellij.codeInsight.ExpectedTypesProvider;
  21 import com.intellij.codeInsight.completion.CompletionUtil;
  22 import com.intellij.codeInsight.lookup.LookupElement;
  23 import com.intellij.codeInsight.template.*;
  24 import com.intellij.codeInsight.template.impl.JavaTemplateUtil;
  25 import com.intellij.openapi.command.WriteCommandAction;
  26 import com.intellij.openapi.components.ServiceManager;
  27 import com.intellij.openapi.project.Project;
  28 import com.intellij.psi.*;
  29 import com.intellij.psi.text.BlockSupport;
  30 import org.jetbrains.annotations.NotNull;
  31 import org.jetbrains.annotations.Nullable;
  32
  33 import java.util.LinkedHashSet;
  34 import java.util.Set;
  35
  36 public class ExpectedTypeMacro implements Macro{
  37
  38   public String getName() {
  39     return "expectedType";
  40   }
  41
  42   public String getDescription() {
  43     return CodeInsightBundle.message("macro.expected.type");
  44   }
  45
  46   public String getDefaultValue() {
  47     return "A";
  48   }
  49
  50   public Result calculateResult(@NotNull Expression[] params, ExpressionContext context) {
  51     PsiType[] types = getExpectedTypes(params, context);
  52     if (types == null || types.length == 0) return null;
  53     return new PsiTypeResult(types[0], context.getProject());
  54   }
  55
  56   public Result calculateQuickResult(@NotNull Expression[] params, ExpressionContext context) {
  57     return null;
  58   }
  59
  60   public LookupElement[] calculateLookupItems(@NotNull Expression[] params, ExpressionContext context) {
  61     PsiType[] types = getExpectedTypes(params, context);
  62     if (types == null || types.length < 2) return null;
  63     Set<LookupElement> set = new LinkedHashSet<LookupElement>();
  64     for (PsiType type : types) {
  65       JavaTemplateUtil.addTypeLookupItem(set, type);
  66     }
  67     return set.toArray(new LookupElement[set.size()]);
  68   }
  69
  70   @Nullable
  71   private static PsiType[] getExpectedTypes(Expression[] params, final ExpressionContext context) {
  72     if (params.length != 0) return null;
  73
  74     final Project project = context.getProject();
  75     PsiDocumentManager.getInstance(project).commitAllDocuments();
  76     PsiType[] types = null;
  77
  78     final int offset = context.getTemplateStartOffset();
  79     PsiFile file = PsiDocumentManager.getInstance(project).getPsiFile(context.getEditor().getDocument());
  80     assert file != null;
  81     final PsiFile fileCopy = (PsiFile)file.copy();
  82
  83     new WriteCommandAction(project) {
  84       protected void run(com.intellij.openapi.application.Result result) throws Throwable {
  85         final BlockSupport blockSupport = ServiceManager.getService(project, BlockSupport.class);
  86         blockSupport.reparseRange(fileCopy, offset, offset, CompletionUtil.DUMMY_IDENTIFIER);
  87       }
  88     }.execute();
  89     PsiElement element = fileCopy.findElementAt(offset);
  90
  91     if (element instanceof PsiIdentifier && element.getParent() instanceof PsiExpression) {
  92       ExpectedTypeInfo[] infos = ExpectedTypesProvider.getInstance(project).getExpectedTypes((PsiExpression)element.getParent(), true);
  93       if (infos.length > 0){
  94         types = new PsiType[infos.length];
  95         for(int i = 0; i < infos.length; i++) {
  96           ExpectedTypeInfo info = infos[i];
  97           types[i] = info.getType();
  98         }
  99       }
 100     }
 101
 102     return types;
 103   }
 104 }