MultipleEmptyLinesFileSetCheck.java

package com.wealthfront.test.filesetcheck;

import java.io.File;
import java.util.List;

import com.puppycrawl.tools.checkstyle.api.AbstractFileSetCheck;
import com.puppycrawl.tools.checkstyle.api.CheckstyleException;
import com.puppycrawl.tools.checkstyle.api.FileContents;
import com.puppycrawl.tools.checkstyle.api.FileText;

public class MultipleEmptyLinesFileSetCheck extends AbstractFileSetCheck {

  @Override
  protected void processFiltered(File file, List<String> lines) throws CheckstyleException {
    if (file.getPath().endsWith(".java")) {
      final int countLessOne = lines.size() - 1;
      final FileContents contents = new FileContents(FileText.fromLines(file, lines));
      for (int lineNumber = 0; lineNumber < countLessOne; lineNumber++) {
        if (contents.lineIsBlank(lineNumber) && contents.lineIsBlank(lineNumber+1)) {
          log(lineNumber+2, "Multiple empty lines.");
          while (lineNumber < countLessOne && contents.lineIsBlank(lineNumber)) {
            lineNumber++;
          }
        }
      }
    }
  }

}