plugins/InspectionGadgets/InspectionGadgetsAnalysis/src/com/siyeh/ig/imports/StaticImportInspectionBase.java

/*
 * Copyright 2000-2013 JetBrains s.r.o.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.siyeh.ig.imports;

import com.intellij.codeInspection.ProblemDescriptor;
import com.intellij.openapi.project.Project;
import com.intellij.psi.*;
import com.intellij.psi.codeStyle.JavaCodeStyleManager;
import com.intellij.psi.util.FileTypeUtils;
import com.intellij.psi.util.InheritanceUtil;
import com.intellij.psi.util.PsiTreeUtil;
import com.intellij.util.IncorrectOperationException;
import com.intellij.util.containers.OrderedSet;
import com.siyeh.InspectionGadgetsBundle;
import com.siyeh.ig.BaseInspection;
import com.siyeh.ig.BaseInspectionVisitor;
import com.siyeh.ig.InspectionGadgetsFix;
import com.siyeh.ig.psiutils.StringUtils;
import org.jetbrains.annotations.NotNull;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

public class StaticImportInspectionBase extends BaseInspection {
  @SuppressWarnings({"PublicField"}) public boolean ignoreSingleFieldImports = false;
  @SuppressWarnings({"PublicField"}) public boolean ignoreSingeMethodImports = false;
  @SuppressWarnings({"PublicField", "UnusedDeclaration"})
  public boolean ignoreInTestCode = false; // keep for compatibility
  @SuppressWarnings("PublicField") public OrderedSet<String> allowedClasses = new OrderedSet<String>();

  @Override
  @NotNull
  public String getDisplayName() {
    return InspectionGadgetsBundle.message("static.import.display.name");
  }

  @Override
  @NotNull
  public String buildErrorString(Object... infos) {
    return InspectionGadgetsBundle.message(
      "static.import.problem.descriptor");
  }

  @Override
  protected InspectionGadgetsFix buildFix(Object... infos) {
    return new StaticImportFix();
  }

  @Override
  public BaseInspectionVisitor buildVisitor() {
    return new StaticImportVisitor();
  }

  private static class StaticImportFix extends InspectionGadgetsFix {

    @Override
    @NotNull
    public String getName() {
      return InspectionGadgetsBundle.message("static.import.replace.quickfix");
    }
    @Override
    @NotNull
    public String getFamilyName() {
      return getName();
    }

    @Override
    public void doFix(Project project, ProblemDescriptor descriptor) throws IncorrectOperationException {
      final PsiImportStaticStatement importStatement = (PsiImportStaticStatement)descriptor.getPsiElement();
      final PsiJavaCodeReferenceElement importReference = importStatement.getImportReference();
      if (importReference == null) {
        return;
      }
      final JavaResolveResult[] importTargets = importReference.multiResolve(false);
      if (importTargets.length == 0) {
        return;
      }
      final boolean onDemand = importStatement.isOnDemand();
      final StaticImportFix.StaticImportReferenceCollector
        referenceCollector = new StaticImportFix.StaticImportReferenceCollector(importTargets, onDemand);
      final PsiJavaFile file = (PsiJavaFile)importStatement.getContainingFile();
      file.accept(referenceCollector);
      final List<PsiJavaCodeReferenceElement> references = referenceCollector.getReferences();
      final Map<PsiJavaCodeReferenceElement, PsiMember> referenceTargetMap = new HashMap<PsiJavaCodeReferenceElement, PsiMember>();
      for (PsiJavaCodeReferenceElement reference : references) {
        final PsiElement target = reference.resolve();
        if (target instanceof PsiMember) {
          final PsiMember member = (PsiMember)target;
          referenceTargetMap.put(reference, member);
        }
      }
      importStatement.delete();
      for (Map.Entry<PsiJavaCodeReferenceElement, PsiMember> entry : referenceTargetMap.entrySet()) {
        removeReference(entry.getKey(), entry.getValue());
      }
    }

    private static void removeReference(PsiJavaCodeReferenceElement reference, PsiMember target) {
      final PsiManager manager = reference.getManager();
      final Project project = manager.getProject();
      final JavaPsiFacade psiFacade = JavaPsiFacade.getInstance(project);
      final PsiElementFactory factory = psiFacade.getElementFactory();
      final PsiClass aClass = target.getContainingClass();
      if (aClass == null) {
        return;
      }
      final String qualifiedName = aClass.getQualifiedName();
      final String text = reference.getText();
      final String referenceText = qualifiedName + '.' + text;
      if (reference instanceof PsiReferenceExpression) {
        final PsiExpression newReference = factory.createExpressionFromText(referenceText, reference);
        final PsiElement insertedElement = reference.replace(newReference);
        JavaCodeStyleManager.getInstance(project).shortenClassReferences(insertedElement);
      }
      else {
        final PsiJavaCodeReferenceElement referenceElement =
          factory.createReferenceElementByFQClassName(referenceText, reference.getResolveScope());
        final PsiElement insertedElement = reference.replace(referenceElement);
        JavaCodeStyleManager.getInstance(project).shortenClassReferences(insertedElement);
      }
    }

    static class StaticImportReferenceCollector extends JavaRecursiveElementVisitor {

      private final JavaResolveResult[] importTargets;
      private final boolean onDemand;
      private final List<PsiJavaCodeReferenceElement> references = new ArrayList<PsiJavaCodeReferenceElement>();

      StaticImportReferenceCollector(@NotNull JavaResolveResult[] importTargets, boolean onDemand) {
        this.importTargets = importTargets;
        this.onDemand = onDemand;
      }

      @Override
      public void visitReferenceElement(PsiJavaCodeReferenceElement reference) {
        super.visitReferenceElement(reference);
        if (isFullyQualifiedReference(reference)) {
          return;
        }
        PsiElement parent = reference.getParent();
        if (parent instanceof PsiImportStatementBase) {
          return;
        }
        while (parent instanceof PsiJavaCodeReferenceElement) {
          parent = parent.getParent();
          if (parent instanceof PsiImportStatementBase) {
            return;
          }
        }
        checkStaticImportReference(reference);
      }

      private void checkStaticImportReference(PsiJavaCodeReferenceElement reference) {
        if (reference.isQualified()) {
          return;
        }
        final PsiElement target = reference.resolve();
        if (!(target instanceof PsiMethod) && !(target instanceof PsiClass) && !(target instanceof PsiField)) {
          return;
        }
        final PsiMember member = (PsiMember)target;
        for (JavaResolveResult importTarget : importTargets) {
          final PsiElement targetElement = importTarget.getElement();
          if (targetElement instanceof PsiMethod || targetElement instanceof PsiField) {
            if (member.equals(targetElement)) {
              addReference(reference);
            }
          }
          else if (targetElement instanceof PsiClass) {
            if (onDemand) {
              final PsiClass containingClass = member.getContainingClass();
              if (InheritanceUtil.isInheritorOrSelf((PsiClass)targetElement, containingClass, true)) {
                addReference(reference);
              }
            }
            else {
              if (targetElement.equals(member)) {
                addReference(reference);
              }
            }
          }
        }
      }

      private void addReference(PsiJavaCodeReferenceElement reference) {
        references.add(reference);
      }

      public List<PsiJavaCodeReferenceElement> getReferences() {
        return references;
      }

      public static boolean isFullyQualifiedReference(PsiJavaCodeReferenceElement reference) {
        if (!reference.isQualified()) {
          return false;
        }
        final PsiElement directParent = reference.getParent();
        if (directParent instanceof PsiMethodCallExpression ||
            directParent instanceof PsiAssignmentExpression ||
            directParent instanceof PsiVariable) {
          return false;
        }
        final PsiElement parent =
          PsiTreeUtil.getParentOfType(reference, PsiImportStatementBase.class, PsiPackageStatement.class, JavaCodeFragment.class);
        if (parent != null) {
          return false;
        }
        final PsiElement target = reference.resolve();
        if (!(target instanceof PsiClass)) {
          return false;
        }
        final PsiClass aClass = (PsiClass)target;
        final String fqName = aClass.getQualifiedName();
        if (fqName == null) {
          return false;
        }
        final String text =
          StringUtils.stripAngleBrackets(reference.getText());
        return text.equals(fqName);
      }
    }
  }

  private class StaticImportVisitor extends BaseInspectionVisitor {

    @Override
    public void visitClass(@NotNull PsiClass aClass) {
      final PsiElement parent = aClass.getParent();
      if (!(parent instanceof PsiJavaFile)) {
        return;
      }
      final PsiJavaFile file = (PsiJavaFile)parent;
      if (FileTypeUtils.isInServerPageFile(file)) {
        return;
      }
      if (!file.getClasses()[0].equals(aClass)) {
        return;
      }
      final PsiImportList importList = file.getImportList();
      if (importList == null) {
        return;
      }
      final PsiImportStaticStatement[] importStatements = importList.getImportStaticStatements();
      for (PsiImportStaticStatement importStatement : importStatements) {
        if (shouldReportImportStatement(importStatement)) {
          registerError(importStatement, importStatement);
        }
      }
    }

    private boolean shouldReportImportStatement(PsiImportStaticStatement importStatement) {
      final PsiJavaCodeReferenceElement importReference = importStatement.getImportReference();
      if (importReference == null) {
        return false;
      }
      PsiClass targetClass = importStatement.resolveTargetClass();
      boolean checked = false;
      while (targetClass != null) {
        final String qualifiedName = targetClass.getQualifiedName();
        if (allowedClasses.contains(qualifiedName)) {
          return false;
        }
        if (checked) {
          break;
        }
        targetClass = targetClass.getContainingClass();
        checked = true;
      }
      if (importStatement.isOnDemand()) {
        return true;
      }
      if (ignoreSingleFieldImports || ignoreSingeMethodImports) {
        boolean field = false;
        boolean method = false;
        // in the presence of method overloading the plain resolve() method returns null
        final JavaResolveResult[] results = importReference.multiResolve(false);
        for (JavaResolveResult result : results) {
          final PsiElement element = result.getElement();
          if (element instanceof PsiField) {
            field = true;
          } else if (element instanceof PsiMethod) {
            method = true;
          }
        }
        if (field && !method) {
          if (ignoreSingleFieldImports) {
            return false;
          }
        }
        else if (method && !field) {
          if (ignoreSingeMethodImports) {
            return false;
          }
        }
      }
      return true;
    }
  }
}