File

The library defines BinaryFileAccess interface to access files for reading and writing. More...

Collaboration diagram for File:

Classes
class	BinaryFileAccess
	BinaryFileAccess provides abstraction on underlying file system. More...
class	FilesystemAccess
	Standard filesystem implementation. More...
class	GlobalFileAccess
	Holds instance of BinaryFileAccess. More...
class	FileException
	Exception for file processing. More...

Detailed Description

The library defines BinaryFileAccess interface to access files for reading and writing.

The library defines BinaryFileAccess interface to access files for reading and writing. Usually default implementation (using filesystem) is sufficient. In case e.g. Android we need special access implementation due to Android restriction. The default GlobalFileAccess is filesystem implementation that is sufficient on most operating systems. The BinaryFileAccess can be implemented also in Java / CSharp bindings.

The library provide convenient static methods BinaryFile::ReadAll() and BinaryFile::WriteAll() that uses GlobalFileAccess to read, write files.

• c++

  class UserFileAccess : public BinaryFileAccess
  {
      std::vector<uint8_t> ReadAll(const std::string& filePath) final
      {
          // do something useful, special
          return FilesystemAccess::Create()->ReadAll(filePath);
      }
   
      void WriteAll(const std::string& filePath,
                    const std::vector<uint8_t>& content) final
      {
          // do something useful, special
          FilesystemAccess::Create()->WriteAll(filePath, content);
      }
  };
   
  static void UseUserManagedFilesystem()
  {
      GlobalFileAccess::Set(std::make_shared<UserFileAccess>());
      auto content = BinaryFile::ReadAll("assets/color.png");
      BinaryFile::WriteAll("output/color_copied_via_file_access.png", content);
  }

• java

  class UserFileAccess extends BinaryFileAccess {
      public Bytes ReadAll(String filePath) {
          try {
              if (!"The Android Project".equals(
                          System.getProperty("java.specification.vendor"))) {
                  return new Bytes(Files.readAllBytes(Paths.get(filePath)));
              } else {
                  // Use Android approach e.g.
                  // IOUtils.toByteArray(getAssets().open(filePath));
                  return new Bytes();
              }
          } catch (IOException e) {
              throw new FileException(e.getMessage());
          }
      }
   
      public void WriteAll(String filePath, Bytes content) {
          try {
              if (!"The Android Project".equals(
                          System.getProperty("java.specification.vendor"))) {
                  Path file = Paths.get(filePath);
                  Files.write(file, content.toByteArray());
              } else {
                  // Use Android approach
              }
          } catch (IOException e) {
              throw new FileException(e.getMessage());
          }
      }
  }
   
  public void UseUserManagedFilesystem() {
      BinaryFileAccess userFileAccess = new UserFileAccess();
      GlobalFileAccess.Set(userFileAccess);
   
      Bytes content = BinaryFile.ReadAll("assets/color.png");
      BinaryFile.WriteAll("output/color_copied_via_file_access.png", content);
  }

• csharp

  class UserFileAccess : BinaryFileAccess
  {
      public override Bytes ReadAll(string filePath)
      {
          // E.g. use csharp approach to read files
          return new Bytes(File.ReadAllBytes(filePath));
      }
   
      public override void WriteAll(string filePath, Bytes content)
      {
          // E.g. use csharp approach to write files
          File.WriteAllBytes(filePath, content.ToArray());
      }
  };
   
  public void UseUserManagedFilesystem()
  {
      BinaryFileAccess userFileAccess = new UserFileAccess();
      GlobalFileAccess.Set(userFileAccess);
   
      Bytes content = BinaryFile.ReadAll("assets/color.png");
      BinaryFile.WriteAll("output/color_copied_via_file_access.png", content);
  }