roman_datamodels_java

API documentation

API documentation for this library is hosted on javadoc.io.

Getting started

Installation

The roman-datamodels package is published on Maven Central. Include the package in your pom.xml like so:

<dependency>
    <groupId>edu.stsci</groupId>
    <artifactId>roman-datamodels</artifactId>
    <version>x.y.z</version>
</dependency>

Usage

The RomanDatamodels#open method is used to read a Roman ASDF file and wrap it in a datamodel instance:

final Path path = Path.of("/path/to/roman_file.asdf");
try (final RomanModel<?> model = RomanDatamodels.open(path)) {
    // ...
}

Next determine what type of datamodel you're dealing with. To test for an image:

if (model instanceof RomanImageModel) {
    final RomanImageModel<?> imageModel = (RomanImageModel<?>) model;
}

To access the image data, call the RomanImageModel#getData method:

final double[][] imageData = imageModel.getData().toArray(new double[0][0]);
final double[] flattenedImageData = imageModel.getData().toArray(new double[0]);

FITS WCS parameters are available from the FitsWcs instance in the metadata:

final FitsWcs fitsWcs = imageModel.getMeta().getFitsWcs();

Running the tests

Set up a Python environment

The test suite uses the Python roman_datamodels package to generate test data, so you'll first need to create a Python environment and install the necessaries. The test-requirements.txt file lists the dependencies needed. Here's an example of creating an environment using conda:

$ conda create --name roman-datamodels-java python=3.13
...
$ conda activate roman-datamodels-java
$ pip install -r test-requirements.txt
...

Set the ASDF_JAVA_TESTS_PYTHON_PATH variable

The ASDF_JAVA_TESTS_PYTHON_PATH environment variable tells the test suite where to find the python binary for your new environment:

$ export ASDF_JAVA_TESTS_PYTHON_PATH=`which python`

Run the tests

Use maven's test command to run the tests:

$ mvn test
...