1、在resource目录下创建目录:META-INF\dubbo\internal
2、在上面的目录下新建文件:com.alibaba.dubbo.rpc.cluster.LoadBalance(文件名就是完整的包名+类名)
文件内容写入
random=com.alibaba.dubbo.rpc.cluster.loadbalance.RandomLoadBalance
roundrobin=com.alibaba.dubbo.rpc.cluster.loadbalance.RoundRobinLoadBalance
leastactive=com.alibaba.dubbo.rpc.cluster.loadbalance.LeastActiveLoadBalance
consistenthash=com.alibaba.dubbo.rpc.cluster.loadbalance.ConsistentHashLoadBalance
上面四个是dubbo自带的,下面这个是自定义的
myloadb=com.alibaba.dubbo.rpc.cluster.loadbalance.MyLoadBalance
3、在自己工程新建包:com.alibaba.dubbo.rpc.cluster.loadbalance
4、在上面的包下新建Java文件:
package com.alibaba.dubbo.rpc.cluster.loadbalance;
import java.util.List;
import com.alibaba.dubbo.common.URL;
import com.alibaba.dubbo.rpc.Invocation;
import com.alibaba.dubbo.rpc.Invoker;
import com.alibaba.dubbo.rpc.RpcException;
import com.alibaba.dubbo.rpc.cluster.LoadBalance;
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
public class MyLoadBalance implements LoadBalance {
private final static Logger logger = LogManager.getLogger(MyLoadBalance.class);
public <T> Invoker<T> select(List<Invoker<T>> invokers, URL url, Invocation invocation) throws RpcException {
logger.info("enter my load balance by spi");
return invokers.get(0);
}
}
5、在引用类上将loadbalance值改为自定义的key
@Reference(loadbalance="myloadb")
private HelloService helloService;
6、观察日志,已生效