Today, with the stunning increase in data, many people are looking for ways to understand and use the data they get in their daily life. Naturally, collecting this volume of information is one issue, and processing it is another challenging issue.
Tika is a tool that can recognize metadata and text in different formats and extract them for you. Tika toolkit, which is written based on Java programming language, allows you to collect and process information and is generally used for indexing search engines, content analysis, etc.
Table of Contents
Features of Tika
Tika generally occupies few memory resources and therefore can be easily embedded in Java programs.
Tika uses various libraries as parser interfaces. By using this feature, the user no longer needs to choose the correct parsing library according to the file type, and this significantly increases the ease of working with this kit.
Tika can use different available parsing libraries in a single program for any type of document.
Tika can detect and extract all metadata models used to describe files.
Tika includes a language detection feature and can be used in documents based on language type.
How to detect the language in Tika
Since Tika is written in the Java programming language, it can identify itself even without the help of metadata. In older versions of Tika, the language of the document was discovered using a LanguageIdentifier instance, but now LanguageIdentifier has been deprecated in favor of web services.
You can now use LanguageDetector abstraction-level subclasses for language detection.
You can also use web services like Google Translate or Microsoft Translator to get more translation services.
Tika is also able to recognize 18 different languages using the getLanguage method of the LanguageIdentifier class. This method returns the name of the language code as a String. Below is a list of the 18 language code pairs identified by Tika:
- da – Danish
- de – German
- et – Estonian – Greek
- en – English
- es – Spanish
- fi – Finnish
- fr – French
- hu – Hungarian
- is – Icelandic
- it – Italian
- NL – Dutch
- no – Norwegian
- pl – Polish
- pt – Portuguese
- ru – Russian
- sv – Swedish
- th- Thai
Application of Tika in Java
Tika toolkit has many different uses, but one of its most important uses is in search engines. Using TIKA, search engines can find metadata on sites and extract it.
TICA is used by many research organizations such as NASA and world-renowned universities. This tool is used for content management, to analyze different values and data.
On the other hand, Tika can detect the type of data in the document by using the MIME detection mechanism and extracting the text and metadata parsing interface, and then it can be used for the user according to the special parsing plugins specified by the user. Slow, summarize.
Tika supports all document types represented in MIME. Whenever a file passes through Tika, the type of document as well as its language is recognized based on the document itself. It should be noted that MIME multipurpose standards are the best available standards for identifying document types. The information on these standards helps the browser in internal interactions.
Whenever the browser comes across a media file, this feature helps to choose a suitable software to display its content. If there is no suitable program to run a specific media document, the user is recommended to install the appropriate software or plug-in on his system.
Tika can also delegate detection to a more appropriate tracker, as the algorithm used by the tracker is implementation dependent. For example, the default tracker first checks for magic bytes, then looks for metadata information, and if the content type is not yet specified, uses the service loader to test all available trackers.
Tika can handle a significant number of file types in different formats: XML, HTML, pdf, java files, jar files, etc. find it, process it and make it available to you.
Content extraction in Tika
Tika uses different types of parser libraries to extract the content and selects the appropriate parser after deciding on the document type. When parsing documents, the parse To String method is generally used. Below is a brief description of the parsing process:
Initially, when we pass a document to Tika, it uses the appropriate detection mechanism, just like the one described earlier, and detects the type of document. Then, by specifying the type of document, Tika selects the appropriate parser from the pool of different parsers. The parser repository contains classes that use other external libraries.
In addition to content, Tika can extract metadata from a file. Metadata is nothing but additional information about the file that accompanies the file. For example, you download a song or an audio file. Its metadata includes things like artist name, album name, and title, and Tika can extract this kind of information from documents.
An Extensible Metadata Platform (XMP) is a standard for processing and storing information about the content of a file. XMP consists of different types of standards for defining, creating, and processing metadata for different types of documents. When using Tika, you can use a method like (metadata. name) to get the names from the file. However, you need a metadata file to call the name. You get this file through the parsing method described above. One of the parameters of metadata is that it holds the metadata after the parsing procedure is completed.
How can we use Tika GUI?
Tika comes with a graphical user interface (GUI) that the user can use. After installing Tika, you can find it in the “GUI” folder.
In the GUI, click open, browse, and select the file to be extracted (drag it to a space in the window). Finally, Tika extracts the content of the files and displays them in five different formats: image metadata, formatted text, plain text, original content, and structured text. You can choose any format you want.
Parsing API in Tika
The API parser is one of the most important parts of the application. This Tikka section summarizes the complex nature of the operation with decomposition and makes it much easier for the user. For this, Tika relies on only one method called the parser, which consists of the following parts:
- InputStream – Parses the generated input data from the document.
- ContentHandler – which receives a sequence of XHTML SAX events from the parsed input document (this handler processes the events and displays the result)
- Metadata (metadata) – is the metadata that parses the characteristics of the metadata in the parser and outside of it.
- Parser text instance (ParseContext) – which conveys text-specific information (can be used to customize the parsing process).
The parser throws an IOException if the input stream cannot be read, a TikaException if the input stream cannot be parsed, and a SAXException if the handler cannot process an event. When parsing, Tika tries to reuse existing parsing libraries, and as a result, most implementing classes are only compatible with such libraries.