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This article shows you how to use elastic-job correctly. The content is concise and easy to understand. It will definitely brighten your eyes. I hope you can get something through the detailed introduction of this article.

1. Docker basic command docker ps lists currently running containers docker ps-a lists all containers docker rm containers ID removes containers docker images all mirrors run zookeeper:docker run-- name elasticzookeeper-p 2181-v / Users/abc/Desktop/WorkSpace/DockerData/elsaticzookeeper/data:/data/-d zookeeperdocker run run a container-name give the container a name (identity Docker cannot be repeated)-p host port: container port-v host directory: container directory, mount disk volume-d background run container docker exec-it container id bash login to container 2, elastic-job

We can refer to the official documents (there are Chinese), very detailed and specific use, http://elasticjob.io/docs/elastic-job-lite/00-overview/

What is elastic-job:

(from the official website) Elastic-Job is a distributed scheduling solution that consists of two independent subprojects, Elastic-Job-Lite and Elastic-Job-Cloud. Elastic-Job-Lite is positioned as a lightweight decentralized solution that provides coordination services for distributed tasks in the form of jar packages; Job-Cloud uses a self-developed Mesos Framework solution to provide additional functions such as resource governance, application distribution and process isolation (PS: I will only say Elastic-Job-Lite here, because I did not study Job-Cloud). To put it simply, Elastic-Job-Lite is a distributed timing task.

How to use elastic-job:1, maven dependency: com.dangdang elastic-job-lite-spring 2.1.5 com.dangdang elastic-job-lite-core 2.1.52, simple column 2.1 write simple scheduled task code public class FirstSimpleJobDemo implements SimpleJob {private static final Logger logger = LoggerFactory.getLogger (FirstSimpleJobDemo.class); @ Override public void execute (ShardingContext shardingContext) {int shardingTotalCount = shardingContext.getShardingTotalCount (); int item = shardingContext.getShardingItem () String shardingParameter = shardingContext.getShardingParameter (); logger.info ("shardingTotalCount: {}, shardingParameter: {}", shardingTotalCount,shardingParameter); logger.info ("- ThredID: {}, current shard item: {}", Thread.currentThread (). GetId (), item);}}

Just implement the SimpleJob class and then implement execute, and write our scheduled task processing logic in execute.

(from the official website) SimpleJob means simple implementation without any encapsulation. You need to implement the SimpleJob interface. The interface provides only a single method for overriding, which is executed on a regular basis. It is similar to the native interface of Quartz, but provides functions such as elastic scaling and sharding. Take a look at the official demo

Public class MyElasticJob implements SimpleJob {@ Override public void execute (ShardingContext context) {switch (context.getShardingItem ()) {case 0: / / do something by sharding item 0 break; case 1: / / do something by sharding item 1 break Case 2: / / do something by sharding item 2 break; / / case n:...}

Using context.getShardingItem () uses multithreading to do different processing of different data.

We can also implement Dataflow type jobs to handle stream jobs, Script type jobs, and script jobs. You can check the official documents for details.

2.2 configuration of scheduled tasks:

A) the registry needs to be configured

The code is as follows:

The parameters mean:

List of server-lists connected Zookeeper servers

The namespace of namespace Zookeeper

The initial value of the interval between base-sleep-time-milliseconds waiting for a retry

The maximum interval time that max-sleep-time-milliseconds waits for retry

Maximum number of maxRetries retries

Please check the configuration manual of the official website for the specific use and parameters of the unit.

B) configure tasks

The parameters mean:

Id Job name

Class job implementation class, which needs to implement ElasticJob interface

A reference to the registry-center-ref registry Bean, which refers to the declaration of reg:zookeeper

Total number of sharding-total-count job shards

Sharding-item-parameters shard sequence numbers and parameters are separated by an equal sign. Multiple key-value pairs are separated by commas, starting with 0, and cannot be greater than or equal to the total number of job shards.

Whether the overwrite local configuration can override the registry configuration, if so, each startup job will be based on the local configuration.

For specific use, please refer to the official configuration manual. It should be noted that the parameter overwrite defaults to false.

3. Operation and maintenance platform:

Download the console code from github, run the code, and type http://localhost:8899/ to access the console. 8899 is the default port number, and you can enter the-p custom port number through the startup script.

Enter the platform, create a new global configuration, fill in the registry name (that is, you can identify which project or which business is related), the registry address (zookeeper address), and the namespace needs to be the same as that configured in the timed task project. Click the Connect button after adding, and you can proceed to the next step after connecting.

Enter the Job Action-> Job dimension to display each scheduled task, and then you can operate each scheduled task.

Enter the Job Action-> Server dimension to display the IP of the server, the number of tasks running, and so on.

The above is how to use elastic-job correctly. Have you learned any knowledge or skills? If you want to learn more skills or enrich your knowledge reserve, you are welcome to follow the industry information channel.

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