Go through a text file containing two tab-separated words per line, finding lines with duplicate words, case-insensitively

FindDups.java

import java.nio.file.Files;
import java.nio.file.Paths;
import com.google.common.base.CharMatcher;
import com.google.common.base.Splitter;
// ...

public class FindDups {
// ...
        public static void main(String[] args) throws Exception {
                String filePath = "/Users/david/Documents/fileee/es_queries/de-lemma-utf8.txt";
                
                List<String> lines = Files.readAllLines(Paths.get(filePath), StandardCharsets.UTF_8);
                Splitter splitter = Splitter.on(CharMatcher.WHITESPACE).trimResults().omitEmptyStrings();
                
                int problemCount = 0;
                
                for (String line : lines) {
                    List<String> splitted = splitter.splitToList(line);
                    if (splitted.size() != 2) {
                        log.warn("Line did not contain 2 tokens: {}", splitted);
                        continue;
                    }
                    
                    String left = splitted.get(0).toLowerCase(Locale.GERMAN);
                    String right = splitted.get(1).toLowerCase(Locale.GERMAN);
                    
                    // log.debug("Left: '{}', right: '{}'", left, right);
                    if (left.equals(right)) {
                        log.warn("Problematic line found: {}", line);
                        problemCount++;
                    }
                }
                
                log.info("{} lines were problematic.", problemCount);
        }
}