private ProviderInfo loadProviders()

in geronimo-mail_2.1_spec/src/main/java/jakarta/mail/Session.java [552:676]
88 lines of code
21 McCabe index (conditional complexity)

    private ProviderInfo loadProviders(final ClassLoader cl) {
        // we create a merged map from reading all of the potential address map entries.  The locations
        // searched are:
        //   0. java.home/conf/javamail.address.map
        //   1. java.home/lib/javamail.address.map
        //   2. META-INF/javamail.address.map
        //   3. META-INF/javamail.default.address.map
        //
        // JDK 1.9 adds a new <java.home>/conf directory to hold configuration
        // files that were previously stored in <java.home>/lib.  When using
        // JavaMail on JDK 1.9, it should look for its (optional) configuration
        // files in the <java.home>/conf directory.
        final ProviderInfo info = new ProviderInfo();

        // NOTE:  Unlike the addressMap, we process these in the defined order.  The loading routine
        // will not overwrite entries if they already exist in the map.

        try {
            File file = new File(System.getProperty("java.home"), "conf/javamail.providers");
            if (!file.exists()){
                file = new File(System.getProperty("java.home"), "lib/javamail.providers");
            }
            final InputStream is = new FileInputStream(file);
            try {
                loadProviders(info, is);
                if (debug) {
                    writeDebug("Loaded lib/javamail.providers from " + file.toString());
                }
            } finally{
                is.close();
            }
        } catch (final SecurityException e) {
            // ignore
        } catch (final IOException e) {
            // ignore
        }

        try {
            final Enumeration e = cl.getResources("META-INF/javamail.providers");
            while (e.hasMoreElements()) {
                final URL url = (URL) e.nextElement();
                if (debug) {
                    writeDebug("Loading META-INF/javamail.providers from " + url.toString());
                }
                final InputStream is = url.openStream();
                try {
                    loadProviders(info, is);
                } finally{
                    is.close();
                }
            }
        } catch (final SecurityException e) {
            // ignore
        } catch (final IOException e) {
            // ignore
        }

        // we could be running in an OSGi environment, so there might be some globally defined
        // providers
        try {
            final Collection<URL> l = MailProviderRegistry.getProviders();
            for (final URL url : l) {
                if (debug) {
                    writeDebug("Loading META-INF/javamail.providers from " + url.toString());
                }
                final InputStream is = url.openStream();
                try {
                    loadProviders(info, is);
                } finally{
                    is.close();
                }
            }
        } catch (final SecurityException e) {
            // ignore
        } catch (final IOException e) {
            // ignore
        }

        try {
            final Enumeration e = cl.getResources("META-INF/javamail.default.providers");
            while (e.hasMoreElements()) {
                final URL url = (URL) e.nextElement();
                if (debug) {
                    writeDebug("Loading javamail.default.providers from " + url.toString());
                }

                final InputStream is = url.openStream();
                try {
                    loadProviders(info, is);
                } finally{
                    is.close();
                }
            }
        } catch (final SecurityException e) {
            // ignore
        } catch (final IOException e) {
            // ignore
        }

        // we could be running in an OSGi environment, so there might be some globally defined
        // providers
        try {
            final Collection<URL> l = MailProviderRegistry.getDefaultProviders();
            for (final URL url : l) {
                if (debug) {
                    writeDebug("Loading META-INF/javamail.providers from " + url.toString());
                }
                final InputStream is = url.openStream();
                try {
                    loadProviders(info, is);
                } finally{
                    is.close();
                }
            }
        } catch (final SecurityException e) {
            // ignore
        } catch (final IOException e) {
            // ignore
        }

        // make sure this is added to the global map.
        providersByClassLoader.put(cl, info);

        return info;
    }