NullPointerException when start provider

[luyuanwan]

• [*] I have searched the issues of this repository and believe that this is not a duplicate.
• [*] I have checked the FAQ of this repository and believe that this is not a duplicate.

Environment

• Dubbo version: 2.7.5-SNAPSHOT
• Dubbo branch: master
• Operating System version: macOS Catalina
• Java version: jdk-11.0.5

Steps to reproduce this issue

1. start zookeeper in localhost and port is 2181
2. write provider-side code
3. start provider, the provider-side code looks like this

public class Application {

	private static String zookeeperHost = System.getProperty("zookeeper.address", "127.0.0.1");

	public static void main(String[] args) throws Exception {
		ServiceConfig<DemoService> service = new ServiceConfig<DemoService>();
		service.setApplication(new ApplicationConfig("first-dubbo-provider"));
		service.setRegistry(new RegistryConfig("zookeeper://" + zookeeperHost + ":2181"));
		service.setInterface(DemoService.class);
		service.setRef(new DemoServiceImpl());
		service.export();

		System.out.println("dubbo service started");
		new CountDownLatch(1).await();
	}
}

Actual Result

But I got an exception.

Exception in thread "main" java.lang.NullPointerException
	at org.apache.dubbo.config.AbstractInterfaceConfig.lambda$useRegistryForConfigIfNecessary$7(AbstractInterfaceConfig.java:628)
	at java.base/java.util.Optional.orElseGet(Optional.java:369)
	at org.apache.dubbo.config.AbstractInterfaceConfig.lambda$useRegistryForConfigIfNecessary$8(AbstractInterfaceConfig.java:620)
	at java.base/java.util.Optional.ifPresent(Optional.java:183)
	at org.apache.dubbo.config.AbstractInterfaceConfig.useRegistryForConfigIfNecessary(AbstractInterfaceConfig.java:618)
	at org.apache.dubbo.config.AbstractInterfaceConfig.checkRegistry(AbstractInterfaceConfig.java:208)
	at org.apache.dubbo.config.ServiceConfig.checkAndUpdateSubConfigs(ServiceConfig.java:303)
	at org.apache.dubbo.config.ServiceConfig.export(ServiceConfig.java:370)
	at com.example.studydubboProvider.Application.main(Application.java:22)

Is this an issue?

[lkj41110]

#5186

[luyuanwan]

@lkj41110 NO , I found it is client is null, not Parameters

Look at this code :

cc.getParameters().put(org.apache.dubbo.remoting.Constants.CLIENT_KEY, rc.getClient());

If cc.getParameters() is NULL, it will throw an NullPointerException. if rc.getClient() is NULL, it will also throw an NullPointerException. #5186 fix the bug the previous one ONLY!

[lkj41110]

Map.put(key,null) dont throw an NullPointerException.
I try to run your code in 2.7.4.1(fix this bug), and found no problem.You can recheck it.

[luyuanwan]

@lkj41110 OK ,I will recheck it. Your dubbo version is 2.7.4.1, mine is 2.7.5-SNAPSHOT(branch master).Thanks anyway.

[chickenlj]

Please follow the release progress posted in this issue: #5219