java/java-impl/src/com/intellij/codeInsight/completion/AbstractExpectedTypeSkipper.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.completion;
  17
  18 import com.intellij.codeInsight.ExpectedTypeInfo;
  19 import com.intellij.codeInsight.generation.OverrideImplementUtil;
  20 import com.intellij.codeInsight.lookup.LookupElement;
  21 import com.intellij.psi.*;
  22 import com.intellij.psi.statistics.StatisticsManager;
  23 import com.intellij.psi.util.PsiTreeUtil;
  24 import com.intellij.psi.util.TypeConversionUtil;
  25
  26 /**
  27  * @author peter
  28  */
  29 public class AbstractExpectedTypeSkipper extends CompletionPreselectSkipper {
  30
  31   private enum Result {
  32     NON_DEFAULT,
  33     STRING,
  34     ABSTRACT,
  35     ACCEPT
  36   }
  37
  38   @Override
  39   public boolean skipElement(LookupElement element, CompletionLocation location) {
  40     return skips(element, location);
  41   }
  42
  43   public static boolean skips(LookupElement element, CompletionLocation location) {
  44     return getSkippingStatus(element, location) != Result.ACCEPT;
  45   }
  46
  47   private static Result getSkippingStatus(final LookupElement item, final CompletionLocation location) {
  48     if (location.getCompletionType() != CompletionType.SMART) return Result.ACCEPT;
  49
  50     final PsiExpression expression = PsiTreeUtil.getParentOfType(location.getCompletionParameters().getPosition(), PsiExpression.class);
  51     if (!(expression instanceof PsiNewExpression)) return Result.ACCEPT;
  52
  53     final Object object = item.getObject();
  54     if (!(object instanceof PsiClass)) return Result.ACCEPT;
  55
  56     if (StatisticsManager.getInstance().getUseCount(CompletionService.STATISTICS_KEY, item, location) > 1) return Result.ACCEPT;
  57
  58     PsiClass psiClass = (PsiClass)object;
  59
  60     int toImplement = 0;
  61     for (final PsiMethod method : psiClass.getMethods()) {
  62       if (method.hasModifierProperty(PsiModifier.ABSTRACT)) {
  63         toImplement++;
  64         if (toImplement > 2) return Result.ABSTRACT;
  65       }
  66     }
  67
  68     toImplement += OverrideImplementUtil.getMethodSignaturesToImplement(psiClass).size();
  69     if (toImplement > 2) return Result.ABSTRACT;
  70
  71     final ExpectedTypeInfo[] infos = JavaCompletionUtil.EXPECTED_TYPES.getValue(location);
  72     boolean isDefaultType = false;
  73     if (infos != null) {
  74       final PsiType type = JavaPsiFacade.getInstance(psiClass.getProject()).getElementFactory().createType(psiClass);
  75       for (final ExpectedTypeInfo info : infos) {
  76         final PsiType infoType = TypeConversionUtil.erasure(info.getType().getDeepComponentType());
  77         final PsiType defaultType = TypeConversionUtil.erasure(info.getDefaultType().getDeepComponentType());
  78         if (!defaultType.equals(infoType) && infoType.isAssignableFrom(type)) {
  79           if (!defaultType.isAssignableFrom(type)) return Result.NON_DEFAULT;
  80           isDefaultType = true;
  81         }
  82       }
  83     }
  84
  85     if (toImplement > 0) return Result.ACCEPT;
  86
  87     if (psiClass.hasModifierProperty(PsiModifier.ABSTRACT)) return Result.ABSTRACT;
  88     if (!isDefaultType && CommonClassNames.JAVA_LANG_STRING.equals(psiClass.getQualifiedName())) return Result.STRING;
  89     if (CommonClassNames.JAVA_LANG_OBJECT.equals(psiClass.getQualifiedName())) return Result.NON_DEFAULT;
  90
  91     return Result.ACCEPT;
  92   }
  93
  94 }