如何将 Pdf 文件转换为文本答案

【问题标题】：How Can I Convert Pdf File to Text如何将 Pdf 文件转换为文本
【发布时间】：2019-11-07 14:28:41
【问题描述】：

我想从 android 的文件管理器中选择一个 pdf 文件并将其转换为文本，以便文本到语音可以读取它。我正在关注来自 android 开发者网站的文档；但是，此示例用于打开文本文件。我正在使用 PdfReader 类/库来打开文件并转换为文本。但我不知道如何将它与 Uri 集成。这是我需要使用 PdfReader 从 pdf 转换为文本的代码

PdfReader pdfReader = new PdfReader(file.getPath());
stringParser = PdfTextExtractor.getTextFromPage(pdfReader, 1).trim();
pdfReader.close();

我正在使用意图调用文件管理器，以便用户可以选择一个 pdf 文件

fab.setOnClickListener(new View.OnClickListener() {
@Override
   public void onClick(View view) {
      intent = new Intent(Intent.ACTION_OPEN_DOCUMENT);
      intent.setType("*/*");
      startActivityForResult(intent, READ_REQUEST_CODE);
   }
});

然后我正在获取 uri 并打开文件

@Override
    protected void onActivityResult(int requestCode, int resultCode, Intent resultData) {
        if (requestCode == READ_REQUEST_CODE && resultCode == Activity.RESULT_OK) {
            if(resultData != null) {
                Uri uri = resultData.getData();
                Toast.makeText(MainActivity.this, filePath , Toast.LENGTH_LONG).show();
                readPdfFile(uri);
            }
        }
    }

    private String readTextFromUri(Uri uri) throws IOException {
        StringBuilder stringBuilder = new StringBuilder();
        try (InputStream inputStream =
                     getContentResolver().openInputStream(uri);
             BufferedReader reader = new BufferedReader(
                     new InputStreamReader(Objects.requireNonNull(inputStream)))) {
            String line;
            while ((line = reader.readLine()) != null) {
                stringBuilder.append(line);
            }
        }
        return stringBuilder.toString();
    }

【问题讨论】：

readPdfFile(uri); ???您没有发布 readPdfFIle() 的代码。你也没有告诉你在哪里以及如何调用发布的函数。例如，您没有告诉您使用 PdfReader 的方式。
@blackpos 阅读帖子中的所有信息。 pdfreader 代码进入 readTextFromUri 中，该方法正在解析文本文件。我需要修改以便它解析一个 pdf 文件

标签： android file-manager pdf-reader

【解决方案1】：

public class SyncPdfTextExtractor {
  // TODO: When you have your own Premium account credentials, put them down here:
  private static final String CLIENT_ID = "FREE_TRIAL_ACCOUNT";
  private static final String CLIENT_SECRET = "PUBLIC_SECRET";
  private static final String ENDPOINT = "https://api.whatsmate.net/v1/pdf/extract?url=";

  /**
   * Entry Point
   */
  public static void main(String[] args) throws Exception {
    // TODO: Specify the URL of your small PDF document (less than 1MB and 10 pages)
    // To extract text from bigger PDf document, you need to use the async method.
    String url = "https://www.harvesthousepublishers.com/data/files/excerpts/9780736948487_exc.pdf";
    SyncPdfTextExtractor.extractText(url);
  }

  /**
   * Extracts the text from an online PDF document.
   */
  public static void extractText(String pdfUrl) throws Exception {
    URL url = new URL(ENDPOINT + pdfUrl);
    HttpURLConnection conn = (HttpURLConnection) url.openConnection();
    conn.setDoOutput(true);
    conn.setRequestMethod("GET");
    conn.setRequestProperty("X-WM-CLIENT-ID", CLIENT_ID);
    conn.setRequestProperty("X-WM-CLIENT-SECRET", CLIENT_SECRET);

    int statusCode = conn.getResponseCode();
    System.out.println("Status Code: " + statusCode);
    InputStream is = null;
    if (statusCode == 200) {
        is = conn.getInputStream();
        System.out.println("PDF text is shown below");
        System.out.println("=======================");
    } else {
        is = conn.getErrorStream();
        System.err.println("Something is wrong:");
    }

    BufferedReader br = new BufferedReader(new InputStreamReader(is)); 
    String output;
    while ((output = br.readLine()) != null) {
        System.out.println(output);
    }
    conn.disconnect();
  }

}
------------------------------------

Copying above code follow below Steps-

Specify the URL of your online PDF document on line 20.
Replace the Client ID and Secret on lines 10 and 11 if you have your own credentials.

【讨论】：

【解决方案2】：

使用这个
摇篮：-

implementation 'com.itextpdf:itextg:5.5.10'

try {
      String parsedText="";
      PdfReader reader = new PdfReader(yourPdfPath);
      int n = reader.getNumberOfPages();
      for (int i = 0; i <n ; i++) {
           parsedText   = parsedText+PdfTextExtractor.getTextFromPage(reader, i+1).trim()+"\n"; //Extracting the content from the different pages
      }
      System.out.println(parsedText);
      reader.close();
   } catch (Exception e) {
      System.out.println(e);
}

【讨论】：