JGroupsChannelLookupImpl

JGroupsChannelLookupImpl.java

package mypackage;

import org.apache.commons.lang.StringUtils;
import org.infinispan.remoting.transport.jgroups.JGroupsChannelLookup;
import org.jgroups.Channel;
import org.jgroups.JChannel;
import org.jgroups.conf.ConfiguratorFactory;
import org.jgroups.conf.ProtocolConfiguration;
import org.jgroups.conf.ProtocolStackConfigurator;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.util.Map;
import java.util.Properties;

/**
 * Channel lookup implementation that creates a JChannel configuration from an XML configuration and then overrides
 * certain properties using the property map that is passed from the (Spring) config.
 * <p/>
 * The configuration file name can be specified in the property map, with the property key
 * <tt>lookupConfigurationFile</tt>. Properties to override should start with <tt>jgroups.</tt>
 * (<tt>PROPERTY_PREFIX</tt>), followed by the protocol name, followed by a dot, followed by the protocol property key.
 */
public class JGroupsChannelLookupImpl implements JGroupsChannelLookup {

    private static final Logger log = LoggerFactory.getLogger(JGroupsChannelLookupImpl.class);

    public static final String PROPERTY_PREFIX = "jgroups.";

    @Override
    public Channel getJGroupsChannel(Properties p) {

        String configurationFile = p.getProperty("lookupConfigurationFile");

        try {
            ProtocolStackConfigurator configurator = ConfiguratorFactory.getStackConfigurator(configurationFile);

            overrideProperties(configurator, p);

            return new JChannel(configurator);
        }
        catch (Exception e) {
            throw new RuntimeException("Could not parse JGroups configuration.", e);
        }

    }

    private void overrideProperties(ProtocolStackConfigurator configurator, Properties p) {

        for (Map.Entry<Object, Object> entry : p.entrySet()) {
            String entryKey = entry.getKey().toString();

            if (StringUtils.startsWith(entryKey, PROPERTY_PREFIX)) {
                overrideProperty(configurator, entryKey.substring(PROPERTY_PREFIX.length()),
                        entry.getValue().toString());
            }
        }

    }

    private void overrideProperty(ProtocolStackConfigurator configurator, String key, String value) {

        int dotIndex = key.indexOf('.');
        if (dotIndex < 0) {
            log.warn("No valid protocol name found in property key: {}", key);
            return;
        }

        String protocolName = key.substring(0, dotIndex);
        String protocolPropertyKey = key.substring(dotIndex + 1);

        for (ProtocolConfiguration protocol : configurator.getProtocolStack()) {
            if (protocol.getProtocolName().equalsIgnoreCase(protocolName)) {
                protocol.getProperties().put(protocolPropertyKey, value);
                return;
            }
        }

        log.warn("Could not find protocol in protocol stack: {}", protocolName);
    }

    @Override
    public boolean shouldStartAndConnect() {
        return true;
    }

    @Override
    public boolean shouldStopAndDisconnect() {
        return true;
    }
}