我如何在 Quartz 中使用 SQLite？

Question

我正在尝试在应用程序中将 quartz 与 SQLite 结合使用。当我阅读文档 here 时，我注意到他们没有在可用的数据库中提及 SQLite。他们说：

JDBCJobStore works with nearly any database, it has been used widely with Oracle, PostgreSQL, MySQL, MS SQLServer, HSQLDB, and DB2. To use JDBCJobStore, you must first create a set of database tables for Quartz to use. You can find table-creation SQL scripts in the “docs/dbTables” directory of the Quartz distribution.

因此，根据这个问题：Which setup script to use for setting up quartz sqlite table? 我使用 derby 脚本作为我的 sqlite 脚本。

问题是当我试图在之前插入的作业中安排触发器时。这是我的代码的一部分：

// and start it off
scheduler.start();

Map<String, String> map = new HashMap<>();
map.put("key", "value");

JobDataMap jdm = new JobDataMap(map);

JobKey key = new JobKey("job1", "key1");

 if(!scheduler.checkExists(key)){
     JobDetail job = newJob(HelloJob.class).withIdentity(key).storeDurably().usingJobData(jdm).build();
     addJob(scheduler, job);

     // Trigger the job to run now, and then repeat every 40 seconds
    Trigger trigger = newTrigger()
         .withIdentity("trigger1", "group1")
         .startNow()
            .forJob(job)
               .withSchedule(simpleSchedule()
                 .withIntervalInSeconds(40)
                 .repeatForever())            
         .build();

    // Tell quartz to schedule the job using our trigger
    scheduler.scheduleJob(trigger); // here is where I get an error
 }

Thread.sleep(60000);

scheduler.shutdown();

我的quartz.properties是这样的：

org.quartz.scheduler.instanceName = MyScheduler
org.quartz.threadPool.threadCount = 5
org.quartz.jobStore.class = org.quartz.impl.jdbcjobstore.JobStoreTX
org.quartz.jobStore.tablePrefix = QRTZ_
org.quartz.dataSource.SQLiteDB.driver = org.sqlite.JDBC
org.quartz.dataSource.SQLiteDB.URL = jdbc:sqlite:bota.db
org.quartz.dataSource.SQLiteDB.maxConnections = 30
org.quartz.jobStore.driverDelegateClass = org.quartz.impl.jdbcjobstore.StdJDBCDelegate
org.quartz.jobStore.dataSource = SQLiteDB

我使用的是 sqlite v-3.8.11.2 和 quartz v-2.2.2。这是我在日志中得到的：

org.quartz.JobPersistenceException: Couldn't store trigger 'group1.trigger1' for 'key1.job1' job:Couldn't retrieve job: not implemented by SQLite JDBC driver [See nested exception: org.quartz.JobPersistenceException: Couldn't retrieve job: not implemented by SQLite JDBC driver [See nested exception: java.sql.SQLException: not implemented by SQLite JDBC driver]]
    at org.quartz.impl.jdbcjobstore.JobStoreSupport.storeTrigger(JobStoreSupport.java:1223)
    at org.quartz.impl.jdbcjobstore.JobStoreSupport.executeVoid(JobStoreSupport.java:1159)
    at org.quartz.impl.jdbcjobstore.JobStoreSupport$VoidTransactionCallback.execute(JobStoreSupport.java:3715)
    at org.quartz.impl.jdbcjobstore.JobStoreSupport$VoidTransactionCallback.execute(JobStoreSupport.java:3713)
    at org.quartz.impl.jdbcjobstore.JobStoreSupport.executeInNonManagedTXLock(JobStoreSupport.java:3799)
    at org.quartz.impl.jdbcjobstore.JobStoreTX.executeInLock(JobStoreTX.java:93)
    at org.quartz.impl.jdbcjobstore.JobStoreSupport.storeTrigger(JobStoreSupport.java:1155)
    at org.quartz.core.QuartzScheduler.scheduleJob(QuartzScheduler.java:932)
    at org.quartz.impl.StdScheduler.scheduleJob(StdScheduler.java:258)
    at javaapplication2.JavaApplication2.main(JavaApplication2.java:174)
Caused by: org.quartz.JobPersistenceException: Couldn't retrieve job: not implemented by SQLite JDBC driver [See nested exception: java.sql.SQLException: not implemented by SQLite JDBC driver]
    at org.quartz.impl.jdbcjobstore.JobStoreSupport.retrieveJob(JobStoreSupport.java:1396)
    at org.quartz.impl.jdbcjobstore.JobStoreSupport.storeTrigger(JobStoreSupport.java:1205)
    ... 9 more
Caused by: java.sql.SQLException: not implemented by SQLite JDBC driver
    at org.sqlite.jdbc4.JDBC4ResultSet.unused(JDBC4ResultSet.java:320)
    at org.sqlite.jdbc4.JDBC4ResultSet.getBlob(JDBC4ResultSet.java:345)
    at com.mchange.v2.c3p0.impl.NewProxyResultSet.getBlob(NewProxyResultSet.java:285)
    at org.quartz.impl.jdbcjobstore.StdJDBCDelegate.getObjectFromBlob(StdJDBCDelegate.java:3190)
    at org.quartz.impl.jdbcjobstore.StdJDBCDelegate.selectJobDetail(StdJDBCDelegate.java:860)
    at org.quartz.impl.jdbcjobstore.JobStoreSupport.retrieveJob(JobStoreSupport.java:1385)
    ... 10 more
BUILD STOPPED (total time: 11 seconds)

Answer 1

问题似乎是 sqlite jdbc 驱动 does not support the method ResultSet.getBlob().

但是 quartz 使用此方法来检索分配给作业的 JobDataMap。

如果您仍想将 quartz 与 sqlite 一起使用，您可以扩展 StdJDBCDelegate and retrieve/set blobs like suggested in this answer。

乍一看似乎只需要覆盖方法

StdJDBCDelegate.getObjectFromBlob() 和
StdJDBCDelegate.getJobDataFromBlob()

因为我不确定以后是否会出现更多问题（例如你可以看到 sqlite jdbc 驱动程序有更多 unsupported ResultSet methods ）我宁愿推荐使用一个数据库开箱即用。

Answer 2

根据 mam10eks 的建议，以下代码对我有用。

package com.example.quartz.sqlite;   

import org.quartz.impl.jdbcjobstore.StdJDBCDelegate;

import java.io.ByteArrayInputStream;
import java.io.EOFException;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.sql.ResultSet;
import java.sql.SQLException;

public class CustomJDBCDelegate extends StdJDBCDelegate {
  @Override
  protected Object getObjectFromBlob(ResultSet rs, String colName) throws ClassNotFoundException, IOException, SQLException {
    byte[] bytes = rs.getBytes(colName);
    Object map = null;
    ByteArrayInputStream bais = null;
    ObjectInputStream ois = null;
    try {
      bais = new ByteArrayInputStream(bytes);
      ois = new ObjectInputStream(bais);
      map = ois.readObject();
    } catch (EOFException ex1) {
      bais.close();
    } catch (IOException e) {
      // Error in de-serialization
      e.printStackTrace();
    }

    return map;
  }

  @Override
  protected Object getJobDataFromBlob(ResultSet rs, String colName) throws ClassNotFoundException, IOException, SQLException {
    return getObjectFromBlob(rs, colName);
  }
}

现在将以下内容放入quartz.properties

org.quartz.jobStore.driverDelegateClass=com.example.quartz.sqlite.CustomJDBCDelegate

我如何在 Quartz 中使用 SQLite？

How can I use SQLite in Quartz?

java

sqlite

quartz-scheduler