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Getting Started with Apache Tika

This document describes how to build Apache Tika from sources and how to start using Tika in an application.

Getting and building the sources

To build Tika from sources you first need to either download a source release or checkout the latest sources from version control.

Once you have the sources, you can build them using the Maven 2 build system. Executing the following command in the base directory will build the sources and install the resulting artifacts in your local Maven repository.

mvn install

If you want to build only the app or the server with the standard parsers, you can save time with:

mvn install -am -pl :tika-app

Or:

mvn install -am -pl :tika-server-standard

See the Maven documentation for more information about the available build options.

Note that you need Java 8 or higher to build Tika.

Build artifacts

The Tika build consists of a number of components and produces the following main binaries:

tika-core/target/tika-core-*.jar
Tika core library. Contains the core interfaces and classes of Tika, but none of the parser implementations.
tika-parsers/tika-parsers-standard/tika-parsers-standard-package/target/tika-parsers-standard-package-*.jar
Tika parsers. Collection of classes that implement the Tika Parser interface based on various external parser libraries. This includes the most commonly used parsers. Users may want to add tika-parser-sqlite3-package and tika-parser-scientific-package or other parser modules.
tika-app/target/tika-app-*.jar
Tika application. Combines the above components and the standard parser libraries into a single runnable jar with a GUI and a command line interface.
tika-server/tika-server-standard/target/tika-server-standard-*.jar
Tika JAX-RS REST application. This is a Jetty web server running Tika REST services with the parsers in tika-parsers-standard-package as described in this page.
tika-bundles/tika-bundle-standard/target/tika-bundle-standard-*.jar
Tika bundle. An OSGi bundle that combines tika-parsers with non-OSGified parser libraries to make them easy to deploy in an OSGi environment.
tika-eval/tika-eval-app/target/tika-eval-app-*.jar
Tika eval module. Commandline tool to assess the output of Tika or compare the output of two different versions of Tika or other text extraction packages.

Using Tika as a Maven dependency

The core library, tika-core, contains the key interfaces and classes of Tika and can be used by itself if you don't need the full set of parsers from the tika-parsers component. The tika-core dependency looks like this:

  <dependency>
    <groupId>org.apache.tika</groupId>
    <artifactId>tika-core</artifactId>
    <version>2.1.0</version>
  </dependency>

If you want to use Tika to parse documents (instead of simply detecting document types, etc.), you'll want to add a dependency on at least tika-parsers-standard-package :

  <dependency>
    <groupId>org.apache.tika</groupId>
    <artifactId>tika-parsers-standard-package</artifactId>
    <version>2.1.0</version>
  </dependency>

Note that adding this dependency will introduce a number of transitive dependencies to your project. You need to make sure that these dependencies won't conflict with your existing project dependencies. You can use the following command in the tika-parsers-standard-package directory to get a full listing of all the dependencies.

$ mvn dependency:tree | grep :compile

You may also want to add one or more of the following dependencies:

  <dependency>
    <groupId>org.apache.tika</groupId>
    <artifactId>tika-parser-sqlite3-package</artifactId>
    <version>2.1.0</version>
  </dependency>
  <dependency>
    <groupId>org.apache.tika</groupId>
    <artifactId>tika-parser-scientific-package</artifactId>
    <version>2.1.0</version>
  </dependency>

You may also consider adding dependencies on modules under the tika-parsers-ml module.

Using Tika in a Gradle-built project

To add a dependency on Apache Tika to your Gradle built project, including the full set of parsers, you should depend on the tika-core artifact and the tika-parsers-standard-package artifact:

dependencies {
    runtime 'org.apache.tika:tika-core:2.1.0'
    runtime 'org.apache.tika:tika-parsers-standard-package:2.1.0'
}

Using Tika in an Ant project

If you are using Apache Ivy as your dependency manager tool with Ant, then to include Tika with the full set of parsers, you should depend on the tika-parsers artifact like this:

    <dependencies>
        <dependency org="org.apache.tika" name="tika-core" rev="2.1.0"/>
        <dependency org="org.apache.tika" name="tika-parsers-standard-package" rev="2.1.0"/>
    </dependencies>

Otherwise, probably the easiest way to use Tika is to include the full tika-app jar on your classpath. For just core functionality, you can add the tika-core jar, but be aware that the full set of parsers have a large number of dependencies which must be included which is very fiddly to do by hand with Ant! To include Tika in your Ant project, you should do something like:

<classpath>
  ... <!-- your other classpath entries -->

  <!-- either: Tika Core only, no parsers -->
  <pathelement location="path/to/tika-core-2.1.0.jar"/>
  <!-- or: Tika with all Parsers-->
  <pathelement location="path/to/tika-app-2.1.0.jar"/>

</classpath>

Using Tika as a command line utility

The Tika application jar (tika-app-*.jar) can be used as a command line utility for extracting text content and metadata from all sorts of files. This runnable jar contains all the dependencies it needs, so you don't need to worry about classpath settings to run it.

The usage instructions are shown below.

usage: java -jar tika-app.jar [option...] [file|port...]

Options:
    -?  or --help          Print this usage message
    -v  or --verbose       Print debug level messages
    -V  or --version       Print the Apache Tika version number

    -g  or --gui           Start the Apache Tika GUI
    -s  or --server        Start the Apache Tika server
    -f  or --fork          Use Fork Mode for out-of-process extraction

    --config=<tika-config.xml>
        TikaConfig file. Must be specified before -g, -s, -f or the dump-x-config !
    --dump-minimal-config  Print minimal TikaConfig
    --dump-current-config  Print current TikaConfig
    --dump-static-config   Print static config
    --dump-static-full-config  Print static explicit config

    -x  or --xml           Output XHTML content (default)
    -h  or --html          Output HTML content
    -t  or --text          Output plain text content
    -T  or --text-main     Output plain text content (main content only)
    -m  or --metadata      Output only metadata
    -j  or --json          Output metadata in JSON
    -y  or --xmp           Output metadata in XMP
    -J  or --jsonRecursive Output metadata and content from all
                           embedded files (choose content type
                           with -x, -h, -t or -m; default is -x)
    -l  or --language      Output only language
    -d  or --detect        Detect document type
           --digest=X      Include digest X (md2, md5, sha1,
                               sha256, sha384, sha512
    -eX or --encoding=X    Use output encoding X
    -pX or --password=X    Use document password X
    -z  or --extract       Extract all attachements into current directory
    --extract-dir=<dir>    Specify target directory for -z
    -r  or --pretty-print  For JSON, XML and XHTML outputs, adds newlines and
                           whitespace, for better readability

    --list-parsers
         List the available document parsers
    --list-parser-details
         List the available document parsers and their supported mime types
    --list-parser-details-apt
         List the available document parsers and their supported mime types in apt format.
    --list-detectors
         List the available document detectors
    --list-met-models
         List the available metadata models, and their supported keys
    --list-supported-types
         List all known media types and related information


    --compare-file-magic=<dir>
         Compares Tika's known media types to the File(1) tool's magic directory

Description:
    Apache Tika will parse the file(s) specified on the
    command line and output the extracted text content
    or metadata to standard output.

    Instead of a file name you can also specify the URL
    of a document to be parsed.

    If no file name or URL is specified (or the special
    name "-" is used), then the standard input stream
    is parsed. If no arguments were given and no input
    data is available, the GUI is started instead.

- GUI mode

    Use the "--gui" (or "-g") option to start the
    Apache Tika GUI. You can drag and drop files from
    a normal file explorer to the GUI window to extract
    text content and metadata from the files.

- Batch mode

    Simplest method.
    Specify two directories as args with no other args:
         java -jar tika-app.jar <inputDirectory> <outputDirectory>


Batch Options:
    -i  or --inputDir          Input directory
    -o  or --outputDir         Output directory
    -numConsumers              Number of processing threads
    -bc                        Batch config file
    -maxRestarts               Maximum number of times the
                               watchdog process will restart the child process.
    -timeoutThresholdMillis    Number of milliseconds allowed to a parse
                               before the process is killed and restarted
    -fileList                  List of files to process, with
                               paths relative to the input directory
    -includeFilePat            Regular expression to determine which
                               files to process, e.g. "(?i)\.pdf"
    -excludeFilePat            Regular expression to determine which
                               files to avoid processing, e.g. "(?i)\.pdf"
    -maxFileSizeBytes          Skip files longer than this value

    Control the type of output with -x, -h, -t and/or -J.

    To modify child process jvm args, prepend "J" as in:
    -JXmx4g or -JDlog4j.configuration=file:log4j.xml.

You can also use the jar as a component in a Unix pipeline or as an external tool in many scripting languages.

# Check if an Internet resource contains a specific keyword
curl http://.../document.doc \
  | java -jar tika-app.jar --text \
  | grep -q keyword

Wrappers

Several wrappers are available to use Tika in another programming language, such as Julia or Python.