plugins/InspectionGadgets/InspectionGadgetsAnalysis/src/com/siyeh/ig/controlflow/SwitchStatementWithTooFewBranchesInspection.java

/*
 * Copyright 2003-2013 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.controlflow;

import com.intellij.codeInspection.ui.SingleIntegerFieldOptionsPanel;
import com.intellij.psi.PsiCodeBlock;
import com.intellij.psi.PsiSwitchStatement;
import com.siyeh.InspectionGadgetsBundle;
import com.siyeh.ig.BaseInspection;
import com.siyeh.ig.BaseInspectionVisitor;
import com.siyeh.ig.psiutils.SwitchUtils;
import org.jetbrains.annotations.NotNull;

import javax.swing.*;

public class SwitchStatementWithTooFewBranchesInspection extends BaseInspection {

  private static final int DEFAULT_BRANCH_LIMIT = 2;

  @SuppressWarnings("PublicField")
  public int m_limit = DEFAULT_BRANCH_LIMIT;

  @Override
  @NotNull
  public String getDisplayName() {
    return InspectionGadgetsBundle.message("switch.statement.with.too.few.branches.display.name");
  }

  @Override
  public JComponent createOptionsPanel() {
    return new SingleIntegerFieldOptionsPanel(InspectionGadgetsBundle.message("switch.statement.with.too.few.branches.min.option"),
                                              this, "m_limit");
  }

  @Override
  @NotNull
  protected String buildErrorString(Object... infos) {
    final Integer branchCount = (Integer)infos[0];
    return InspectionGadgetsBundle.message("switch.statement.with.too.few.branches.problem.descriptor", branchCount);
  }

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

  private class SwitchStatementWithTooFewBranchesVisitor extends BaseInspectionVisitor {

    @Override
    public void visitSwitchStatement(@NotNull PsiSwitchStatement statement) {
      final PsiCodeBlock body = statement.getBody();
      if (body == null) {
        return;
      }
      final int branchCount = SwitchUtils.calculateBranchCount(statement);
      if (branchCount == 0) {
        return; // // do not warn when no switch branches are present at all
      }
      if (branchCount >= m_limit) {
        return;
      }
      registerStatementError(statement, Integer.valueOf(branchCount));
    }
  }
}