manifestutil

ManifestUtil.java

package org.foo.manifestutil;

import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.net.URL;
import java.util.jar.Manifest;

import org.apache.commons.io.IOUtils;

// https://stackoverflow.com/q/1272648/447503
public final class ManifestUtil {
    
    private ManifestUtil() {}
    
    public static Manifest getManifest(final Class<?> clazz) throws IOException {
        final String resource = clazz.getName().replace('.', '/') + ".class";
        final String fullPath = clazz.getClassLoader().getResource(resource).toString();
        String archivePath = fullPath.substring(0, fullPath.length() - resource.length() - 1);
        if (archivePath.endsWith(WEB_INF_CLASSES)) {
            // Required for wars
            archivePath = archivePath.substring(0, archivePath.length() - WEB_INF_CLASSES.length());
        }
        
        final String manifestPath = archivePath + "/META-INF/MANIFEST.MF";
        InputStream in = null;
        try {
            in = new URL(manifestPath).openStream();
            return new Manifest(in);
        } catch (final FileNotFoundException e) {
            return null;
        } finally {
            IOUtils.closeQuietly(in);
        }
    }
    
    private static final String WEB_INF_CLASSES = "/WEB-INF/classes";
}