java-jq is not a re-implementation of jq in Java; instead, it embeds the necessary jq and Oniguruma native libraries in a jar file, and then uses Java Native Access (JNA) to call the embedded libraries in a Java-friendly way.

The distribution of java-jq includes native JQ 1.6 libraries for all major platforms (Mac, Windows and Linux), and includes a statically linked version of Oniguruma 5.9.6 to avoid any runtime compatibility issues.

java-jq was heavily inspired by jjq.

Using Java-JQ is very easy.

First, let's get a reference to the Native JQ library. This class is a thread-safe singleton.

JqLibrary library = ImmutableJqLibrary.of();

Now, let's create a JQ request. A "request" is an immutable bean that contains three basic elements: a reference to the JQ library we created above, the JSON input you want to transform, and the JQ filter expression that you want to execute.

final JqRequest request = ImmutableJqRequest.builder() //
        .lib(library) //
        .input("{\"a\":[1,2,3,4,5],\"b\":\"hello\"}") //
        .filter(".") //
        .build();

As a final step, let's execute the request.

final JqResponse response = request.execute();
if( response.hasErrors() ) {
   // display errors in response.getErrors()
} else {
   System.out.println( "JQ output: " + response.getOutput());
}

As of version 1.1.0, java-jq successfully executes the complete jq test suite, including all tests in jq.test, onig.test, base64.test, and optional.test.

java-jq supports modules as well. To use modules, include the directory paths where your modules can be found with your JqRequest as follows:

final JqRequest request = ImmutableJqRequest.builder() //
        .lib(library) //
        .input("your json goes here") //
        .filter(".") //
        .addModulePath(new File("/some/modules/can/be/found/here")) //
        .addModulePath(new File("/other/modules/can/be/found/here")) //
        .build();

The library is available on Maven Central.

Add the following to your pom.xml:

<repositories>
    <repository>
        <id>central</id>
        <name>Central Repository</name>
        <url>https://repo.maven.apache.org/maven2</url>
        <releases>
            <enabled>true</enabled>
        </releases>
    </repository>
</repositories>

...

<dependency>
    <groupId>com.arakelian</groupId>
    <artifactId>java-jq</artifactId>
    <version>1.3.0</version>
    <scope>test</scope>
</dependency>

Add the following to your build.gradle:

repositories {
  mavenCentral()
}

dependencies {
  testCompile 'com.arakelian:java-jq:1.3.0'
}

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