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1, Interface Parameter Description: Take the commodity list according to the keywords and extract pinduoduo commodities, including the title, baby main map, price, sales volume, shopkeeper's nickname, logistics expenses, store location, baby link, etc. the price is as low as a few cents, and the quantity is large or even free. Please add me, or ...

`public class AtomicInteger extends Number implements java.io.Serializable { // setup to use Unsafe.compareAndSwapInt for updates private static final Unsafe unsafe = Unsafe.getUnsafe(); private static final long valueOffset; static { try { // Calculates the offset of the variable value in the clas ...

Background kafka Manager (now renamed CMAK) is the most popular kafka cluster management tool. It was first opened by Yahoo. Users can perform some simple cluster management operations on the Web interface.We install everything here from scratch.This JDK version selects [jdk1.8.0_301]; JDK8 official website download address. The version of ...

HDFS transparent encryption, Keystore and Hadoop KMS, encryption area The data in HDFS will be saved in the form of blocks in the local disk of each data node, but these blocks are in clear text. If you directly access the directory where the block is located under the operating system, you can directly view the contents through the cat comman ...

Local operation mode Basic introduction Spark's Local operation mode is also called Local operation mode and pseudo distributed mode. This is called Local mode because all spark processes in this mode run in the virtual machine of a Local machine without any resource manager. It mainly uses multiple threads of a single machine to simulate spa ...

explain:         1. Prepare three virtual machines, refer to: Construction of CentOS7 cluster environment (taking 3 sets as an example)         2. Configure secret free login between virtual machines: Reference: CentOS7 cluster configuration password free login         3. Install jd ...

1. Batch query The speed of ES is already very fast, but it can even be faster. Combine multiple requests into one to avoid the network delay and overhead of processing each request separately. If you need to retrieve many documents from ES, using multi get or mget API to put these retrieval requests in one request will retrieve all docume ...

2021SC@SDUSC Bolt node analysis of Trident 2021SC@SDUSC SubTopologyBolt type is the basic unit running in Trident, but it is not a real Bolt node. Trident will use tridentboltexecution to interface adapt SubTopologyBolt. Tridentboltexecution inherits from the IRichBolt interface and is the Bolt node that actually runs in Trident. It provide ...

Absrtact: This article mainly introduces the use of the basic api of hadoop hdfs. Including Windows side dependency configuration and Maven dependency configuration. The last is the actual operation, including: obtaining the remote hadoop hdfs connection and a series of operations on it, including; Folder creation, file upload, file download, f ...

This article is transferred from: Le byteThis article mainly explains: RedisFor more Java related information, you can pay attention to the official account number: 999Cache cacheCache conceptA cache is a replica set of original data stored on a computer for easy access.Common caching scenarios for Web projectsBuffer breakdownConcept:For some k ...