이미지 비교 (image comparision)

public class ImageCompare {

  private String originPath;
  private String cdnPath;

  private boolean same = true;

  int b1 = 0, b2 = 0, pos = 1;

  public ImageCompare(String originPath, String cdnPath) {
    this.originPath = originPath;
    this.cdnPath = cdnPath;
  }

  public boolean compare() throws IOException {

    try (
        BufferedInputStream compare1 = new BufferedInputStream(new URL(originPath).openStream());
        BufferedInputStream compare2 = new BufferedInputStream(new URL(cdnPath).openStream());
    ) {
      while (b1 != -1 && b2 != -1) {
        if (b1 != b2) {
          log.info(" two file was different. : {}, {}", originPath, cdnPath);
          same = false;
          break;
        }
        pos++;
        b1 = compare1.read();
        b2 = compare2.read();
      }
    }

    return same;
  }
}

참고 : https://dzone.com/articles/comparing-files-in-java

Comparing Files in Java - DZone Java

This lesson in Java NIO and memory mapping involves creating a simple Java application to compare files while safeguarding performance.

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