• How to use the source command in Linux


    The source command is a built-in shell command that reads and executes commands from files in the current shell session. The source command is usually used to keep and change environment variables in the current shell. In short, source is a script that will run the execute command in the current shell.The source command can […]

  • [case50] talk about fscheckpointstorage in flick


    order This paper mainly studies fscheckpoint storage of Flink CheckpointStorage flink-runtime_2.11-1.7.0-sources.jar!/org/apache/flink/runtime/state/CheckpointStorage.java /** * CheckpointStorage implements the durable storage of checkpoint data and metadata streams. * An individual checkpoint or savepoint is stored to a {@link CheckpointStorageLocation}, * created by this class. */ public interface CheckpointStorage { boolean supportsHighlyAvailableStorage(); boolean hasDefaultSavepointLocation(); CompletedCheckpointStorageLocation resolveCheckpoint(String externalPointer) throws IOException; […]

  • C# Interface


    C# interfaceInterface defines the syntax contract that all classes should follow when inheriting the interface. The interface defines the “what” part of the syntax contract, and the derived class defines the “how” part of the syntax contract. An interface defines properties, methods, and events, which are members of the interface. The interface contains only member […]

  • Xuecheng online project summary – day3 CMS page management development


    Series articles: Summary of Xuecheng online project – Day1 CMS server building Xuecheng online project summary – Day2 CMS front end development Xuecheng online project summary – day3 CMS page management development Xuecheng online project summary – day4 page static Xuecheng online project summary – Day5 rabbitmq message queue Custom query page After the database […]

  • Talk about fscheckpoint streamfactory of Flink


    order This paper mainly studies the fscheckpoint streamfactory of Flink CheckpointStreamFactory flink-runtime_2.11-1.7.0-sources.jar!/org/apache/flink/runtime/state/CheckpointStreamFactory.java /** * A factory for checkpoint output streams, which are used to persist data for checkpoints. * * <p>Stream factories can be created from the {@link CheckpointStorage} through * {@link CheckpointStorage#resolveCheckpointStorageLocation(long, CheckpointStorageLocationReference)}. */ public interface CheckpointStreamFactory { CheckpointStateOutputStream createCheckpointStateOutputStream(CheckpointedStateScope scope) throws IOException; abstract […]

  • Manual golang basic data structure and algorithm heap sorting


    origin Recently read < < my first algorithm book > > ([Japan] Ishida Baohui; Miyazaki Xiuyi)This series of notes is intended to use golang exercises Heap sort Heap sorting is characterized by the use of the heap in the data structure. First, store all the data in the heap and build the heap in descending […]

  • Shell introduction series (I): Variables


    variable The variables in the shell are weakly typed and can be used as in PHP. The difference from PHP variables is that the variables in the function are global variables by default. At the same time, there is the concept of environment variablesWhen a shell script executes, you can pass variables into the script […]

  • Google Developer Conference: tensorflow tips you have to know


    Google development days China 2018 was recently held in China. It’s a pity that Xiaobian stayed in Hefei due to non resistant factors and couldn’t attend. But Xiaobian’s friends were lucky to attend the meeting and brought first-hand information about tensolfow. Here we follow Xiaobian to focus on the best application of tensorflow in the […]

  • Electronic engineer, do you really know type-C?


    This paper mainly looks at type-C from the perspective of electronic engineers, not from the perspective of consumer electronics. Before talking about the type-C interface, let’s talk about the development of USB. 01. USB overview It has been 21 years since usb1.0 was officially released in January 1996 (usb3.2 was released in September 2017). Over […]

  • Talk about flynk’s timecharacteristic


    order This paper mainly studies the timecharacteristic of Flink TimeCharacteristic flink-streaming-java_2.11-1.7.0-sources.jar!/org/apache/flink/streaming/api/TimeCharacteristic.java /** * The time characteristic defines how the system determines time for time-dependent * order and operations that depend on time (such as time windows). */ @PublicEvolving public enum TimeCharacteristic { /** * Processing time for operators means that the operator uses the system […]

  • Talk about the eventtime of Flink


    order This paper mainly studies the eventtime of Flink SourceFunction flink-streaming-java_2.11-1.7.0-sources.jar!/org/apache/flink/streaming/api/functions/source/SourceFunction.java /** * Interface that source functions use to emit elements, and possibly watermarks. * * @param <T> The type of the elements produced by the source. */ @Public // Interface might be extended in the future with additional methods. interface SourceContext<T> { /** * […]

  • [C + + learning notes] it’s enough to have an in-depth understanding of C + + structures and utilities!


    Structs and unions are data types that already exist in C language. C + + extends them. The biggest change is to allow member functions to be defined in structures and public bodies. The following will explain their characteristics and usage through examples.   1.struct The following is a C + + program that uses […]