Apache Tika
This short tutorial is all about extracting data with the Apache Tika library. Read below to find out how to extract your own data.
Overview
Apache Tika is a library that allows you to extract data from PDF, XLS, PDT, etc. Apache Tika using a decorator pattern so you can easily fit it to your needs.
Adding Dependency
XML
<dependency>
<groupId>org.apache.tika</groupId>
<artifactId>tika-core</artifactId>
<version>1.26</version>
</dependency>
Apache Tika in Action
Java
public class DzoneApacheTikaExample {
public static void main(String[] args) throws TikaException, IOException, SAXException {
DzoneApacheTikaExample example = new DzoneApacheTikaExample();
String value = example.readFromPdf("test-reading.pdf");
System.out.println("Data read from PDF: ");
System.out.println(value);
}
public String readFromPdf(String readFromFileName) throws IOException, TikaException, SAXException {
InputStream stream = this.getClass()
.getClassLoader()
.getResourceAsStream(readFromFileName);
Parser parser = new AutoDetectParser();
ContentHandler handler = new BodyContentHandler();
Metadata metadata = new Metadata();
ParseContext context = new ParseContext();
parser.parse(stream, handler, metadata, context);
return handler.toString();
}
}BodyContentHandler: Collects all information inside the body tag.
Metadata: All metadata collected during the parsing will be stored there.
ParseContext: Used to pass context information to Apache Tika parser.
ContentHandler: Based on decorator patter so we can make complex handling.
For example, let's write parsed data into a file:
Java
public class DzoneApacheTikaExample {
public static void main(String[] args) throws TikaException, IOException, SAXException {
DzoneApacheTikaExample example = new DzoneApacheTikaExample();
example.writeParsedDataToFile("capitals.xlsx", "/Users/ali_zhagparov/Desktop/excel-content.txt");
}
public void writeParsedDataToFile(String readFromFileName, String writeToFileName) throws IOException, TikaException, SAXException {
InputStream stream = this.getClass().getClassLoader().getResourceAsStream(readFromFileName);
File yourFile = new File(writeToFileName);
yourFile.createNewFile(); // if file already exists, will do nothing
FileOutputStream fileOutputStream = new FileOutputStream(yourFile, false);
Parser parser = new AutoDetectParser();
ContentHandler handler = new BodyContentHandler(new WriteOutContentHandler(fileOutputStream));
Metadata metadata = new Metadata();
ParseContext context = new ParseContext();
parser.parse(stream, handler, metadata, context);
}
}
Apache Tika
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