flinksql 自定義udf

1、pom.xml(注意：pom中有多餘的jar，本人暫時未進行剔除)

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>org.example</groupId>
    <artifactId>udf</artifactId>
    <version>1.0-SNAPSHOT</version>

    <properties>
        <maven.compiler.source>8</maven.compiler.source>
        <maven.compiler.target>8</maven.compiler.target>
    </properties>

    <dependencies>

        <!-- Either... -->
        <dependency>
            <groupId>org.apache.flink</groupId>
            <artifactId>flink-table-api-java-bridge_2.11</artifactId>
            <version>1.10.2</version>
            <scope>provided</scope>
        </dependency>
        <!-- or... -->
        <dependency>
            <groupId>org.apache.flink</groupId>
            <artifactId>flink-table-api-scala-bridge_2.11</artifactId>
            <version>1.10.2</version>
            <scope>provided</scope>
        </dependency>
        <!-- Either... (for the old planner that was available before Flink 1.9) -->
        <dependency>
            <groupId>org.apache.flink</groupId>
            <artifactId>flink-table-planner_2.11</artifactId>
            <version>1.10.2</version>
            <scope>provided</scope>
        </dependency>
        <!-- or.. (for the new Blink planner) -->
        <dependency>
            <groupId>org.apache.flink</groupId>
            <artifactId>flink-table-planner-blink_2.11</artifactId>
            <version>1.10.2</version>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>org.apache.flink</groupId>
            <artifactId>flink-streaming-scala_2.11</artifactId>
            <version>1.10.2</version>
            <scope>provided</scope>
        </dependency>

        <dependency>
            <groupId>org.apache.flink</groupId>
            <artifactId>flink-table-common</artifactId>
            <version>1.10.2</version>
            <scope>provided</scope>
        </dependency>

    </dependencies>

</project>

2、java代碼：

package com.jd;

import org.apache.flink.table.functions.ScalarFunction;

public class HashCode extends ScalarFunction {
    public String eval(String s) {
        return "liuhaijing:"+s;
    }
}

3、接下來就可以參照官網來使用了，配上截屏