org.springframework.integration.ip.udp.MulticastRule.java Source code

Introduction

Here is the source code for org.springframework.integration.ip.udp.MulticastRule.java

Source

/*
 * Copyright 2015-2017 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.springframework.integration.ip.udp;

import java.net.InetAddress;
import java.net.MulticastSocket;

import org.apache.commons.logging.LogFactory;
import org.junit.Assume;
import org.junit.rules.TestWatcher;
import org.junit.runner.Description;
import org.junit.runners.model.Statement;

import org.springframework.integration.ip.util.SocketTestUtils;
import org.springframework.util.Assert;

/**
 * @author Artem Bilan
 * @since 4.3
 */
public class MulticastRule extends TestWatcher {

    public static String GROUP = "225.6.7.8";

    private final String group;

    private final String nic;

    private boolean skip;

    public MulticastRule() {
        this(GROUP);
    }

    public MulticastRule(String group) {
        Assert.hasText(group, "'group' must not be empty");
        this.group = group;
        System.setProperty("java.net.preferIPv4Stack", "true");
        System.setProperty("multicast.group", this.group);
        try {
            this.nic = checkMulticast();
        } catch (Exception e) {
            throw new IllegalStateException(e);
        }
        if (this.nic != null) {
            System.setProperty("multicast.local.address", this.nic);
        }
    }

    private String checkMulticast() throws Exception {
        String nic = SocketTestUtils.chooseANic(true);
        if (nic == null) { // no multicast support
            this.skip = true;
            return null;
        }
        try {
            MulticastSocket socket = new MulticastSocket();
            socket.joinGroup(InetAddress.getByName(this.group));
            socket.close();
        } catch (Exception e) {
            this.skip = true;
            // Ignore. Assume no Multicast - skip the test.
        }
        return nic;
    }

    public String getGroup() {
        return group;
    }

    public String getNic() {
        return nic;
    }

    @Override
    public Statement apply(Statement base, Description description) {
        if (this.skip) {
            LogFactory.getLog(this.getClass()).info("No Multicast support; test skipped");
            return new Statement() {

                @Override
                public void evaluate() throws Throwable {
                    Assume.assumeTrue(false);
                }
            };
        } else {
            return super.apply(base, description);
        }
    }

}