URL을 이용해서 HTTP 기반으로 이미지를 다운로드하는 코드입니다.

일단, 인터넷 경로를 통해 다운을 받기 위해서는 AndroidManifest.xml 파일에 다음 permission을 추가해줘야 합니다.

Permission

<uses-permission android:name="android.permission.INTERNET" />

URL을 이용하여 Bitmap 가져오는 함수

private Bitmap getImageFromURL(String imageUrl) {
    Bitmap bitmap = null;

    try {
      URL url = new URL(imageUrl);
      URLConnection connection = url.openConnection();
      connection.connect();

      int size = conn.getContentLength();
      BufferedInputStream bis = new BufferedInputStream(connection.getInputStream(), size);
      bitmap = BitmapFactory.decodeStream(bis);

      bis.close();
    } catch (Exception e) {
      e.printStackTrace();
    }

    return bitmap;
  }

모바일 디바이스내 내부/외부 저장소의 용량을 확인하는 함수입니다.

MemoryUtil.java

public class MemoryUtil {

  public static void showStatus() {
    Log.i("", "< MemoryStatus >");
    Log.i("", "Total Internal MemorySize : " + getFormattedSize(GetTotalInternalMemorySize()));
    Log.i("",
        "Available Internal MemorySize : " + getFormattedSize(GetAvailableInternalMemorySize()));

    if (IsExternalMemoryAvailable() == true) {
      Log.i("", "Total External MemorySize : " + getFormattedSize(GetTotalExternalMemorySize()));
      Log.i("",
          "Available External MemorySize : " + getFormattedSize(GetAvailableExternalMemorySize()));
    }
  }

  private static boolean IsExternalMemoryAvailable() {
    return android.os.Environment.getExternalStorageState()
        .equals(android.os.Environment.MEDIA_MOUNTED);
  }

  private static long GetTotalInternalMemorySize() {
    File path = Environment.getDataDirectory();
    StatFs stat = new StatFs(path.getPath());
    long blockSize = stat.getBlockSize();
    long totalBlocks = stat.getBlockCount();

    return totalBlocks * blockSize;
  }

  private static long GetAvailableInternalMemorySize() {
    File path = Environment.getDataDirectory();
    StatFs stat = new StatFs(path.getPath());
    long blockSize = stat.getBlockSize();
    long availableBlocks = stat.getAvailableBlocks();

    return availableBlocks * blockSize;
  }

  private static long GetTotalExternalMemorySize() {
    if (IsExternalMemoryAvailable() == true) {
      File path = Environment.getExternalStorageDirectory();
      StatFs stat = new StatFs(path.getPath());
      long blockSize = stat.getBlockSize();
      long totalBlocks = stat.getBlockCount();

      return totalBlocks * blockSize;
    }

    return -1;
  }

  private static long GetAvailableExternalMemorySize() {
    if (IsExternalMemoryAvailable() == true) {
      File path = Environment.getExternalStorageDirectory();
      StatFs stat = new StatFs(path.getPath());
      long blockSize = stat.getBlockSize();
      long availableBlocks = stat.getAvailableBlocks();

      return availableBlocks * blockSize;
    }

    return -1;
  }

  private static String getFormattedSize(long size) {
    String suffix = "";

    if (size >= 1024) {
      suffix = "KB";
      size /= 1024;
      if (size >= 1024) {
        suffix = "MB";
        size /= 1024;
      }
    }

    StringBuilder sb = new StringBuilder(Long.toString(size));

    int commaOffset = sb.length() - 3;
    while (commaOffset > 0) {
      sb.insert(commaOffset, ',');
      commaOffset -= 3;
    }

    sb.append(suffix);

    return sb.toString();
  }
}