在java中使用Apache Tika從PDF文件中提取文本

Question

try { 
     File file = new File("Example.pdf"); 
     String content = new Tika().parseToString(file); 
     System.out.println("The Content: " + content); 
    } catch (Exception e) { 
     e.printStackTrace(); 
    } 

我已經導入java.io.File和導入org.apache.tika.Tika; 但在運行此代碼我得到的錯誤是這樣的：

Exception in thread "main" java.lang.NoSuchMethodError: org.slf4j.spi.LocationAwareLogger.log(Lorg/slf4j/Marker;Ljava/lang/String;ILjava/lang/String;Ljava/lang/Throwable;)V at org.apache.commons.logging.impl.SLF4JLocationAwareLog.warn(SLF4JLocationAwareLog.java:162) at org.apache.pdfbox.pdmodel.font.FileSystemFontProvider.loadDiskCache(FileSystemFontProvider.java:461) at org.apache.pdfbox.pdmodel.font.FileSystemFontProvider.(FileSystemFontProvider.java:217) at org.apache.pdfbox.pdmodel.font.FontMapperImpl$DefaultFontProvider.(FontMapperImpl.java:130) at org.apache.pdfbox.pdmodel.font.FontMapperImpl.getProvider(FontMapperImpl.java:149) at org.apache.pdfbox.pdmodel.font.FontMapperImpl.findFont(FontMapperImpl.java:413) at org.apache.pdfbox.pdmodel.font.FontMapperImpl.findFontBoxFont(FontMapperImpl.java:376) at org.apache.pdfbox.pdmodel.font.FontMapperImpl.getFontBoxFont(FontMapperImpl.java:350) at org.apache.pdfbox.pdmodel.font.PDType1Font.(PDType1Font.java:146) at org.apache.pdfbox.pdmodel.font.PDType1Font.(PDType1Font.java:79) at org.apache.pdfbox.pdmodel.font.PDFontFactory.createFont(PDFontFactory.java:62) at org.apache.pdfbox.pdmodel.PDResources.getFont(PDResources.java:143) at org.apache.pdfbox.contentstream.operator.text.SetFontAndSize.process(SetFontAndSize.java:60) at org.apache.pdfbox.contentstream.PDFStreamEngine.processOperator(PDFStreamEngine.java:838) at org.apache.pdfbox.contentstream.PDFStreamEngine.processStreamOperators(PDFStreamEngine.java:495) at org.apache.pdfbox.contentstream.PDFStreamEngine.processStream(PDFStreamEngine.java:469) at org.apache.pdfbox.contentstream.PDFStreamEngine.processPage(PDFStreamEngine.java:150) at org.apache.pdfbox.text.LegacyPDFStreamEngine.processPage(LegacyPDFStreamEngine.java:139) at org.apache.pdfbox.text.PDFTextStripper.processPage(PDFTextStripper.java:391) at org.apache.tika.parser.pdf.PDF2XHTML.processPage(PDF2XHTML.java:147) at org.apache.pdfbox.text.PDFTextStripper.processPages(PDFTextStripper.java:319) at org.apache.pdfbox.text.PDFTextStripper.writeText(PDFTextStripper.java:266) at org.apache.tika.parser.pdf.PDF2XHTML.process(PDF2XHTML.java:117) at org.apache.tika.parser.pdf.PDFParser.parse(PDFParser.java:167) at org.apache.tika.parser.CompositeParser.parse(CompositeParser.java:280) at org.apache.tika.parser.CompositeParser.parse(CompositeParser.java:280) at org.apache.tika.parser.AutoDetectParser.parse(AutoDetectParser.java:135) at org.apache.tika.Tika.parseToString(Tika.java:527) at org.apache.tika.Tika.parseToString(Tika.java:642) at java_programs.PdfParse.main(PdfParse.java:22)

Answer 1

以下似乎爲我工作。 我得到了我想要的字符串，但我也在控制檯中打印了一些警告。

[在Windows上]我編譯，這樣運行：

javac -cp .;tika-app-1.16.jar Test.java 

java -cp .;tika-app-1.16.jar Test 

什麼蒂卡罐子您使用的？ 我添加了另一種方法（tikaPdfTest()）來顯示從PDF獲取文本的不同方式，可能會對您有所幫助。

import java.io.File; 
import org.apache.tika.Tika; 

import java.io.File; 
import java.io.FileInputStream; 
import java.io.IOException; 

import org.apache.tika.exception.TikaException; 
import org.apache.tika.metadata.Metadata; 
import org.apache.tika.parser.ParseContext; 
import org.apache.tika.parser.pdf.PDFParser; 
import org.apache.tika.sax.BodyContentHandler; 
import org.apache.tika.Tika; 

import org.xml.sax.SAXException; 

public class Test { 
    public static void main(final String[] args) { 
     //Your way 
     try { 
      File file = new File("Example.pdf"); 
      String content = new Tika().parseToString(file); 
      System.out.println("The Content: " + content); 
     } catch (final Exception e) { 
      e.printStackTrace(); 
     } 

     //Another way 
     try { 
      System.out.println("The contents:\t[" + Test.tikaPdfTest("Example.pdf") + "]"); 
     } catch (final Exception e) { 
      e.printStackTrace(); 
     } 
    } 

    public static String tikaPdfTest(final String fileName) throws IOException, SAXException, TikaException { 
     try(final FileInputStream inputstream = new FileInputStream(new File(fileName))) { 
      final BodyContentHandler handler = new BodyContentHandler(); 
      new PDFParser().parse(inputstream, handler, new Metadata(), new ParseContext()); 
      return handler.toString().trim(); 
     } 
    } 
}