Java的嵌套流

Question

快速的問題： 我如何引用嵌套流的父元素這樣的：

jpegDir.stream() 
    .parallel() 
    .map(E -> createDimentionArray(E.getDescription(1), E.getDescription(3))) 
    .filter(E -> E != null) 
    .forEach(E -> images.stream() 
     .filter(J -> J.getType().contains(".jpg")) 
     .forEach(I -> I.setSize(E)) 
    ); 

從最後forEach父元素E爲string型。有沒有辦法讓我在setSize()方法中引用E？

Answer 1

UPDATE

剛剛發佈的固定代碼，所以如果別人有困難時，他們可以看看：

public class Inderxer { 

    public void indexFolder(Path path) throws IOException { 
     List<Image> images = new LinkedList<>(); 
     Files.walk(path).parallel().forEach(E -> { 
     if (!E.toFile().isDirectory() && !E.toFile().getName().contains(".DS") && FilenameUtils.getExtension(E.toFile().toString()) != ".kmz") { 
      try { 

       Metadata metadata = ImageMetadataReader.readMetadata(E.toFile()); 
       if (FilenameUtils.getExtension(E.toFile().toString()).contains("jpg")) { 
        List<Directory> dirs = metadata.getDirectoriesOfType(JpegDirectory.class).stream().collect(Collectors.toList()); 
        images.add(new Image(E.getFileName().toString(), FilenameUtils.getExtension(E.toFile().toString()), dirs)); 
       } else { 
        List<Directory> dirs = metadata.getDirectoriesOfType(PngDirectory.class).stream().collect(Collectors.toList()); 
        images.add(new Image(E.getFileName().toString(), FilenameUtils.getExtension(E.toFile().toString()), dirs)); 
       } 

      } catch (ImageProcessingException e) { 
       e.printStackTrace(); 
      } catch (IOException e) { 
       e.printStackTrace(); 
      } 
     } 
    }); 
    images.stream() 
      .forEach(M -> M.getDirectory().stream() 
        .forEach(D -> { 
         if (!M.getType().equals("png")) { 
          M.setSize(createDimentionArray(D.getDescription(1), D.getDescription(3), "jpg")); 
         } else { 
          M.setSize(createDimentionArray(D.getDescription(1), D.getDescription(2), "png")); 
         } 
        })); 

    images.forEach(System.out::println); 
} 

private String createDimentionArray(String h, String w, String type) { 
    String res = ""; 
    if (type.equals("jpg")) { 
     if (h != null && w != null) { 
      String[] hsplit = h.split("pixels"); 
      String[] wsplit = w.split("pixels"); 
      if (hsplit[0] != null && wsplit[0] != null) { 
       res = hsplit[0]; //Hight 
       res += wsplit[0]; //Width 
       res += "\n"; 
      } 
      return res; 
     } else { 
      return null; 
     } 

    } else { 
     if (h != null && w != null) { 
      String[] hsplit = h.split("pixels"); 
      String[] wsplit = w.split("pixels"); 
      if (hsplit[0] != null && wsplit[0] != null) { 
       res = hsplit[0]; //Hight 
       res += " "; 
       res += wsplit[0]; //Width 
       res += "\n"; 
      } 
      return res; 
     } else { 
      return null; 
     } 
    } 
    } 
}