java/java-impl/src/com/intellij/refactoring/extractclass/ExtractClassHandler.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.refactoring.extractclass;
  17
  18 import com.intellij.openapi.actionSystem.DataContext;
  19 import com.intellij.openapi.editor.CaretModel;
  20 import com.intellij.openapi.editor.Editor;
  21 import com.intellij.openapi.editor.ScrollType;
  22 import com.intellij.openapi.editor.ScrollingModel;
  23 import com.intellij.openapi.project.Project;
  24 import com.intellij.psi.*;
  25 import com.intellij.psi.util.PsiTreeUtil;
  26 import com.intellij.refactoring.HelpID;
  27 import com.intellij.refactoring.RefactorJBundle;
  28 import com.intellij.refactoring.RefactoringActionHandler;
  29 import com.intellij.refactoring.util.CommonRefactoringUtil;
  30 import org.jetbrains.annotations.NotNull;
  31
  32 public class ExtractClassHandler implements RefactoringActionHandler {
  33
  34   protected static String getRefactoringName() {
  35     return RefactorJBundle.message("extract.class");
  36   }
  37
  38   protected static String getHelpID() {
  39     return HelpID.ExtractClass;
  40   }
  41
  42   public void invoke(@NotNull Project project, Editor editor, PsiFile file, DataContext dataContext) {
  43     final ScrollingModel scrollingModel = editor.getScrollingModel();
  44     scrollingModel.scrollToCaret(ScrollType.MAKE_VISIBLE);
  45     final CaretModel caretModel = editor.getCaretModel();
  46     final int position = caretModel.getOffset();
  47     final PsiElement element = file.findElementAt(position);
  48
  49     final PsiMember selectedMember = PsiTreeUtil.getParentOfType(element, PsiMember.class, true);
  50     if (selectedMember == null) {
  51       //todo
  52       return;
  53     }
  54
  55     PsiClass containingClass = selectedMember.getContainingClass();
  56
  57     if (containingClass == null && selectedMember instanceof PsiClass) {
  58       containingClass = (PsiClass)selectedMember;
  59     }
  60
  61     if (containingClass == null) {
  62       CommonRefactoringUtil.showErrorHint(project, editor, RefactorJBundle.message("cannot.perform.the.refactoring") + RefactorJBundle.message("the.caret.should.be.positioned.within.a.class.to.be.refactored"),
  63                                           null, getHelpID());
  64       return;
  65     }
  66     if (containingClass.isInterface()) {
  67       CommonRefactoringUtil.showErrorHint(project, editor, RefactorJBundle.message("cannot.perform.the.refactoring") + RefactorJBundle.message("the.selected.class.is.an.interface"), null,
  68                                           getHelpID());
  69       return;
  70     }
  71     if (containingClass.isEnum()) {
  72       CommonRefactoringUtil.showErrorHint(project, editor, RefactorJBundle.message("cannot.perform.the.refactoring") + RefactorJBundle.message("the.selected.class.is.an.enumeration"), null,
  73                                           getHelpID());
  74       return;
  75     }
  76     if (containingClass.isAnnotationType()) {
  77       CommonRefactoringUtil.showErrorHint(project, editor, RefactorJBundle.message("cannot.perform.the.refactoring") + RefactorJBundle.message("the.selected.class.is.an.annotation.type"), null,
  78                                           getHelpID());
  79       return;
  80     }
  81     if (classIsInner(containingClass) && !containingClass.hasModifierProperty(PsiModifier.STATIC)) {
  82       CommonRefactoringUtil.showErrorHint(project, editor, RefactorJBundle.message("cannot.perform.the.refactoring") + RefactorJBundle.message("the.refactoring.is.not.supported.on.non.static.inner.classes"),
  83                                           null, getHelpID());
  84       return;
  85     }
  86     if (classIsTrivial(containingClass)) {
  87       CommonRefactoringUtil.showErrorHint(project, editor, RefactorJBundle.message("cannot.perform.the.refactoring") + RefactorJBundle.message("the.selected.class.has.no.members.to.extract"), null,
  88                                           getHelpID());
  89       return;
  90     }
  91     new ExtractClassDialog(containingClass, selectedMember).show();
  92   }
  93
  94   private static boolean classIsInner(PsiClass aClass) {
  95     return PsiTreeUtil.getParentOfType(aClass, PsiClass.class, true) != null;
  96   }
  97
  98   public void invoke(@NotNull Project project, @NotNull PsiElement[] elements, DataContext dataContext) {
  99     if (elements.length != 1) {
 100       return;
 101     }
 102     final PsiClass containingClass = PsiTreeUtil.getParentOfType(elements[0], PsiClass.class, false);
 103
 104     final PsiMember selectedMember = PsiTreeUtil.getParentOfType(elements[0], PsiMember.class, false);
 105     if (containingClass == null) {
 106       return;
 107     }
 108     if (classIsTrivial(containingClass)) {
 109       return;
 110     }
 111     new ExtractClassDialog(containingClass, selectedMember).show();
 112   }
 113
 114   private static boolean classIsTrivial(PsiClass containingClass) {
 115     if (containingClass.getFields().length == 0) {
 116       final PsiMethod[] methods = containingClass.getMethods();
 117       if (methods.length == 0) return true;
 118       for (PsiMethod method : methods) {
 119         if (method.getBody() != null) return false;
 120       }
 121       return true;
 122     }
 123     return false;
 124   }
 125 }