BigDecimalEqualsInspection.java

/*
 * Copyright 2003-2012 Dave Griffith, Bas Leijdekkers
 *
 * 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.numeric;

import com.intellij.codeInspection.ProblemDescriptor;
import com.intellij.openapi.project.Project;
import com.intellij.psi.*;
import com.intellij.util.IncorrectOperationException;
import com.siyeh.InspectionGadgetsBundle;
import com.siyeh.ig.BaseInspection;
import com.siyeh.ig.BaseInspectionVisitor;
import com.siyeh.ig.InspectionGadgetsFix;
import com.siyeh.ig.PsiReplacementUtil;
import com.siyeh.ig.psiutils.ExpressionUtils;
import com.siyeh.ig.psiutils.MethodCallUtils;
import org.jetbrains.annotations.NotNull;

public class BigDecimalEqualsInspection extends BaseInspection {

  @Override
  @NotNull
  public String getDisplayName() {
    return InspectionGadgetsBundle.message("big.decimal.equals.display.name");
  }

  @Override
  @NotNull
  protected String buildErrorString(Object... infos) {
    return InspectionGadgetsBundle.message("big.decimal.equals.problem.descriptor");
  }

  @Override
  public InspectionGadgetsFix buildFix(Object... infos) {
    return new BigDecimalEqualsFix();
  }

  private static class BigDecimalEqualsFix extends InspectionGadgetsFix {
    @Override
    @NotNull
    public String getFamilyName() {
      return InspectionGadgetsBundle.message("big.decimal.equals.replace.quickfix");
    }

    @Override
    public void doFix(Project project, ProblemDescriptor descriptor) throws IncorrectOperationException {
      final PsiIdentifier name = (PsiIdentifier)descriptor.getPsiElement();
      final PsiReferenceExpression expression = (PsiReferenceExpression)name.getParent();
      assert expression != null;
      final PsiMethodCallExpression call = (PsiMethodCallExpression)expression.getParent();
      final PsiExpression qualifier = expression.getQualifierExpression();
      if (qualifier == null) {
        return;
      }
      final String qualifierText = qualifier.getText();
      assert call != null;
      final PsiExpressionList argumentList = call.getArgumentList();
      final PsiExpression[] args = argumentList.getExpressions();
      final String argText = args[0].getText();
      PsiReplacementUtil.replaceExpression(call, qualifierText + ".compareTo(" + argText + ")==0");
    }
  }

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

  private static class BigDecimalEqualsVisitor extends BaseInspectionVisitor {

    @Override
    public void visitMethodCallExpression(@NotNull PsiMethodCallExpression expression) {
      super.visitMethodCallExpression(expression);
      if (!MethodCallUtils.isEqualsCall(expression)) {
        return;
      }
      final PsiReferenceExpression methodExpression = expression.getMethodExpression();
      final PsiExpressionList argumentList = expression.getArgumentList();
      final PsiExpression[] arguments = argumentList.getExpressions();
      if (arguments.length == 0) {
        return;
      }
      final PsiExpression arg = arguments[0];
      if (!ExpressionUtils.hasType(arg, "java.math.BigDecimal")) {
        return;
      }
      final PsiExpression qualifier = methodExpression.getQualifierExpression();
      if (!ExpressionUtils.hasType(qualifier, "java.math.BigDecimal")) {
        return;
      }
      final PsiElement context = expression.getParent();
      if (context instanceof PsiExpressionStatement) {
        //cheesy, but necessary, because otherwise the quickfix will
        // produce uncompilable code (out of merely incorrect code).
        return;
      }
      registerMethodCallError(expression);
    }
  }
}