National Archives DROID embed

DroidFileIdentifier.java

import uk.gov.nationalarchives.droid.core.BinarySignatureIdentifier;
import uk.gov.nationalarchives.droid.core.SignatureParseException;
import uk.gov.nationalarchives.droid.core.interfaces.IdentificationRequest;
import uk.gov.nationalarchives.droid.core.interfaces.IdentificationResult;
import uk.gov.nationalarchives.droid.core.interfaces.IdentificationResultCollection;
import uk.gov.nationalarchives.droid.core.interfaces.RequestIdentifier;
import uk.gov.nationalarchives.droid.core.interfaces.resource.FileSystemIdentificationRequest;
import uk.gov.nationalarchives.droid.core.interfaces.resource.RequestMetaData;

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.URI;

public class DroidFileIdentifier {

    private static final BinarySignatureIdentifier SIG_IDENTIFER = new BinarySignatureIdentifier();
    static {
        SIG_IDENTIFER.setSignatureFile("DROID_SignatureFile_V65.xml");

        try {
            SIG_IDENTIFER.init();
        } catch (SignatureParseException e) {
            throw new ExceptionInInitializerError(e);
        }

        // set to -1 for whole file scan
        SIG_IDENTIFER.setMaxBytesToScan(1024);
    }

    public static void displayMime(File file) throws IOException {


        String fileName = file.getCanonicalPath();
        URI uri = file.toURI();

        RequestMetaData metaData = new RequestMetaData(file.length(), file.lastModified(), fileName);
        RequestIdentifier identifier = new RequestIdentifier(uri);

        InputStream in = null;
        IdentificationRequest request = new FileSystemIdentificationRequest(metaData, identifier);

        try {
            in = new FileInputStream(file);
            request.open(in);
            IdentificationResultCollection sigResults = SIG_IDENTIFER.matchBinarySignatures(request);
            IdentificationResultCollection extResults = SIG_IDENTIFER.matchExtensions(request, false);


            for (IdentificationResult result : sigResults.getResults()) {
                System.out.printf(
                    "File : %s => mime: %s, type name: %s\n",
                    file.getCanonicalPath(),
                    result.getMimeType(),
                    result.getName()
                );
            }

            for (IdentificationResult result : extResults.getResults()) {
                System.out.printf(
                    "File : %s => mime: %s, type name: %s\n",
                    file.getCanonicalPath(),
                    result.getMimeType(),
                    result.getName()
                );
            }

        } catch (Exception e) {
            throw new IOException(e);
        }

        return null;
    }

    public static void main(String[] args) throws Exception {
        String[] files = new String[] {
            "MyFile.txt"
        };

        for (String file : files) {
            DroidFileIdentifier.displayMime(new File(file));
        }

    }

}

pom.xml

<dependencies>

        <dependency>
            <groupId>uk.gov.nationalarchives</groupId>
            <artifactId>droid-core</artifactId>
            <version>${version.droid}</version>
            <scope>compile</scope>
        </dependency>

        <dependency>
            <groupId>uk.gov.nationalarchives</groupId>
            <artifactId>droid-core-interfaces</artifactId>
            <version>${version.droid}</version>
            <scope>compile</scope>
        </dependency>
        
        <dependency>
            <groupId>uk.gov.nationalarchives</groupId>
            <artifactId>droid-results</artifactId>
            <version>${version.droid}</version>
        </dependency>
        
        <dependency>
            <groupId>uk.gov.nationalarchives</groupId>
            <artifactId>droid-command-line</artifactId>
            <version>${version.droid}</version>
            <scope>compile</scope>
        </dependency>
</dependencies>

This small Gist was tested with DROID version 6.1. A signature file is available from here: https://raw.github.com/digital-preservation/droid/master/droid-results/src/main/resources/DROID_SignatureFile_V65.xml