feat: cron scheduler support

build.gradle.kts

@@ -3,6 +3,8 @@ plugins {
     id("jacoco")
     id("signing")
     id("maven-publish")
+    // cannot read variable in plugins
+    id("org.gradlex.extra-java-module-info") version "1.4.1"
 }
 
 jacoco {

gradle.properties

@@ -4,6 +4,8 @@ project.version=1.0.2-SNAPSHOT
 project.url=https://github.com/arjenzhou/bm-kit
 
 gradle.wrapper.version=8.2.1
+
 jcoco.version=0.8.9
 junit-bom.version=5.9.1
-slf4j.version=2.0.7
+slf4j.version=2.0.7
+quertz.version=2.3.2

lazy/src/main/java/com/arjenzhou/kit/lazy/UnsetException.java

@@ -1,7 +1,7 @@
 package com.arjenzhou.kit.lazy;
 
 /**
- * Threw when evaluation virtual Lazy node
+ * Thrown when evaluation virtual Lazy node
  *
  * @author [email protected]
  * @since 2023/7/8

scheduler/.gitignore

@@ -0,0 +1,42 @@
+.gradle
+build/
+!gradle/wrapper/gradle-wrapper.jar
+!**/src/main/**/build/
+!**/src/test/**/build/
+
+### IntelliJ IDEA ###
+.idea/modules.xml
+.idea/jarRepositories.xml
+.idea/compiler.xml
+.idea/libraries/
+*.iws
+*.iml
+*.ipr
+out/
+!**/src/main/**/out/
+!**/src/test/**/out/
+
+### Eclipse ###
+.apt_generated
+.classpath
+.factorypath
+.project
+.settings
+.springBeans
+.sts4-cache
+bin/
+!**/src/main/**/bin/
+!**/src/test/**/bin/
+
+### NetBeans ###
+/nbproject/private/
+/nbbuild/
+/dist/
+/nbdist/
+/.nb-gradle/
+
+### VS Code ###
+.vscode/
+
+### Mac OS ###
+.DS_Store

scheduler/build.gradle.kts

@@ -0,0 +1,21 @@
+dependencies {
+    implementation("org.quartz-scheduler:quartz:${project.property("quertz.version")}")
+}
+
+plugins {
+    id("org.gradlex.extra-java-module-info")
+}
+
+extraJavaModuleInfo {
+    // quartz has not supported JPMS yet
+    module("quartz-${project.property("quertz.version")}.jar", "org.quertz.scheduler.quartz", "${project.property("quertz.version")}") {
+        requires("org.slf4j")
+        requires("java.desktop")
+        requires("java.rmi")
+        exportAllPackages()
+    }
+    // quartz related dependencies, whose versions are depend on quartz, not global used.
+    module("HikariCP-java7-2.4.13.jar", "hikari", "2.4.13")
+    module("c3p0-0.9.5.4.jar", "c3p0", "0.9.5.4")
+    module("mchange-commons-java-0.2.15.jar", "mchange.commons.java", "0.2.15")
+}

scheduler/src/main/java/com/arjenzhou/kit/scheduler/SchedulerRunner.java

@@ -0,0 +1,31 @@
+package com.arjenzhou.kit.scheduler;
+
+import com.arjenzhou.kit.scheduler.job.internal.JobRunner;
+import org.quartz.*;
+import org.quartz.impl.StdSchedulerFactory;
+
+/**
+ * portal to run scheduler jobs
+ *
+ * @author [email protected]
+ * @since 2023/7/21
+ */
+public class SchedulerRunner {
+    /**
+     * run all scheduler jobs
+     *
+     * @throws SchedulerException when scheduler failed to start
+     */
+    public static void run() throws SchedulerException {
+        SchedulerFactory factory = new StdSchedulerFactory();
+        Scheduler scheduler = factory.getScheduler();
+        JobDetail jobRunner = JobBuilder.newJob(JobRunner.class).build();
+        Trigger trigger = TriggerBuilder.newTrigger()
+                .startNow()
+                // In every second, check whether each job can run or not, till forever
+                .withSchedule(SimpleScheduleBuilder.simpleSchedule().withIntervalInSeconds(1).repeatForever())
+                .build();
+        scheduler.scheduleJob(jobRunner, trigger);
+        scheduler.start();
+    }
+}

scheduler/src/main/java/com/arjenzhou/kit/scheduler/job/InMemorySchedulerJob.java

@@ -0,0 +1,32 @@
+package com.arjenzhou.kit.scheduler.job;
+
+import java.util.Date;
+
+/**
+ * Scheduler Job whose context stored in memory, thus cannot being restored from any persistence storage.
+ *
+ * @author [email protected]
+ * @since 2023/7/23
+ */
+public abstract class InMemorySchedulerJob implements ScheduledJob {
+    /**
+     * the last time this job completed.
+     */
+    private Date lastRunTime = new Date(0L);
+
+    /**
+     * execute the job
+     */
+    public abstract void execute();
+
+    @Override
+    public void start() {
+        execute();
+        lastRunTime = new Date();
+    }
+
+    @Override
+    public Date getLastRunTime() {
+        return lastRunTime;
+    }
+}

scheduler/src/main/java/com/arjenzhou/kit/scheduler/job/Scheduled.java

@@ -0,0 +1,19 @@
+package com.arjenzhou.kit.scheduler.job;
+
+import java.lang.annotation.*;
+
+/**
+ * Indicates that the Scheduled Job when to start.
+ *
+ * @author [email protected]
+ * @since 2023/7/21
+ */
+@Documented
+@Retention(RetentionPolicy.RUNTIME)
+@Target(ElementType.TYPE)
+public @interface Scheduled {
+    /**
+     * the quartz cron expression
+     */
+    String cronExpression();
+}

scheduler/src/main/java/com/arjenzhou/kit/scheduler/job/ScheduledJob.java

@@ -0,0 +1,22 @@
+package com.arjenzhou.kit.scheduler.job;
+
+import java.util.Date;
+
+/**
+ * Job to run at specific condition.
+ * All subclass should be provided to this class, and declared in META-INF/services/com.arjenzhou.kit.scheduler.job.ScheduledJob
+ *
+ * @author [email protected]
+ * @since 2023/7/21
+ */
+public interface ScheduledJob {
+    /**
+     * how the ScheduledJob perform action
+     */
+    void start();
+
+    /**
+     * @return the latest time the job completed
+     */
+    Date getLastRunTime();
+}

scheduler/src/main/java/com/arjenzhou/kit/scheduler/job/internal/JobHolder.java

@@ -0,0 +1,40 @@
+package com.arjenzhou.kit.scheduler.job.internal;
+
+import com.arjenzhou.kit.scheduler.job.ScheduledJob;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.util.List;
+import java.util.ServiceLoader;
+import java.util.stream.Collectors;
+
+/**
+ * Container which holds all instances that implemented ScheduledJob
+ *
+ * @author [email protected]
+ * @see ScheduledJob
+ * @since 2023/7/23
+ */
+public class JobHolder {
+    private static final Logger LOG = LoggerFactory.getLogger("JOB FACTORY");
+    /**
+     * All jobs instances
+     */
+    private static final List<ScheduledJob> SCHEDULED_JOBS;
+
+    static {
+        ServiceLoader<ScheduledJob> jobServiceLoader = ServiceLoader.load(ScheduledJob.class);
+        SCHEDULED_JOBS = jobServiceLoader.stream().map(ServiceLoader.Provider::get).toList();
+        String loadedJobs = SCHEDULED_JOBS.stream().map(j -> j.getClass().getTypeName()).collect(Collectors.joining("\n"));
+        LOG.info("load " + SCHEDULED_JOBS.size() + " jobs: \n" + loadedJobs);
+        LOG.info("check whether your service is declared in /META-INF/serivces/com.arjenzhou.kit.scheduler.job.ScheduledJob, " +
+                "or provides with com.arjenzhou.kit.scheduler.job.ScheduledJob or not.");
+    }
+
+    /**
+     * @return all scheduled jobs
+     */
+    public static List<ScheduledJob> getAllJobs() {
+        return SCHEDULED_JOBS;
+    }
+}

scheduler/src/main/java/com/arjenzhou/kit/scheduler/job/internal/JobRunner.java

@@ -0,0 +1,48 @@
+package com.arjenzhou.kit.scheduler.job.internal;
+
+import com.arjenzhou.kit.scheduler.job.Scheduled;
+import org.quartz.CronExpression;
+import org.quartz.Job;
+import org.quartz.JobExecutionContext;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.text.ParseException;
+import java.util.Date;
+
+/**
+ * runner to run all scheduled jobs
+ *
+ * @author [email protected]
+ * @since 2023/7/21
+ */
+public class JobRunner implements Job {
+    private static final Logger LOG = LoggerFactory.getLogger("JOB RUNNER");
+
+    /**
+     * for JobBuilder to invoke
+     */
+    public JobRunner() {
+    }
+
+    @Override
+    public void execute(JobExecutionContext context) {
+        Date now = new Date();
+        JobHolder.getAllJobs().forEach(scheduledJob -> {
+            Scheduled scheduled = scheduledJob.getClass().getAnnotation(Scheduled.class);
+            String expression = scheduled.cronExpression();
+            try {
+                CronExpression cronExpression = new CronExpression(expression);
+                Date lastRunTime = scheduledJob.getLastRunTime();
+                Date nextValidTimeAfterLastRun = cronExpression.getNextValidTimeAfter(lastRunTime);
+                // it is not the time to start this job
+                if (nextValidTimeAfterLastRun.after(now)) {
+                    return;
+                }
+                scheduledJob.start();
+                LOG.info("Job " + scheduledJob.getClass().getTypeName() + " started");
+            } catch (ParseException ignored) {
+            }
+        });
+    }
+}

scheduler/src/main/java/module-info.java

@@ -0,0 +1,15 @@
+/**
+ * @author [email protected]
+ * @since 2023/7/23
+ */
+module bm.kit.scheduler.main {
+    requires transitive org.quertz.scheduler.quartz;
+    requires org.slf4j;
+
+    exports com.arjenzhou.kit.scheduler;
+    exports com.arjenzhou.kit.scheduler.job;
+    exports com.arjenzhou.kit.scheduler.job.internal to org.quertz.scheduler.quartz;
+
+    // all jobs should be provided by this, for SPI reflection
+    uses com.arjenzhou.kit.scheduler.job.ScheduledJob;
+}

scheduler/src/test/java/module-info.java

@@ -0,0 +1,16 @@
+import com.arjenzhou.kit.scheduler.job.ScheduledJob;
+import test.com.arjenzhou.kit.scheduler.TestJob;
+
+/**
+ * @author [email protected]
+ * @since 2023/7/23
+ */
+module bm.kit.scheduler.test {
+    exports test.com.arjenzhou.kit.scheduler;
+
+    requires bm.kit.scheduler.main;
+    requires org.slf4j;
+    requires org.junit.jupiter.api;
+
+    provides ScheduledJob with TestJob;
+}

scheduler/src/test/java/test/com/arjenzhou/kit/scheduler/SchedulerTest.java

@@ -0,0 +1,19 @@
+package test.com.arjenzhou.kit.scheduler;
+
+import com.arjenzhou.kit.scheduler.SchedulerRunner;
+import org.junit.jupiter.api.Test;
+import org.quartz.SchedulerException;
+
+import java.util.concurrent.TimeUnit;
+
+/**
+ * @author [email protected]
+ * @since 2023/7/21
+ */
+public class SchedulerTest {
+    @Test
+    public void test() throws SchedulerException, InterruptedException {
+        SchedulerRunner.run();
+        TimeUnit.SECONDS.sleep(15);
+    }
+}

scheduler/src/test/java/test/com/arjenzhou/kit/scheduler/TestJob.java

@@ -0,0 +1,24 @@
+package test.com.arjenzhou.kit.scheduler;
+
+import com.arjenzhou.kit.scheduler.job.InMemorySchedulerJob;
+import com.arjenzhou.kit.scheduler.job.Scheduled;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.util.Date;
+
+/**
+ * Test Job which runs in every 5 seconds, and prints current system time.
+ *
+ * @author [email protected]
+ * @since 2023/7/23
+ */
+@Scheduled(cronExpression = "*/5 * * * * ?")
+public class TestJob extends InMemorySchedulerJob {
+    private static final Logger LOG = LoggerFactory.getLogger(TestJob.class);
+
+    @Override
+    public void execute() {
+        LOG.info(new Date().toString());
+    }
+}

scheduler/src/test/resources/META-INF/services/com.arjenzhou.kit.scheduler.job.ScheduledJob

@@ -0,0 +1 @@
+test.com.arjenzhou.kit.scheduler.TestJob

settings.gradle.kts

@@ -1,4 +1,5 @@
 rootProject.name = "bm-kit"
 include("statemachine")
 include("base")
-include("lazy")
+include("lazy")
+include("scheduler")