如何在Quartz中使用SQLite？

Question

我正在嘗試在應用程序中將石英與SQLite結合使用。 當我在這里閱讀文檔時，我注意到他們沒有在可用的數據庫中提及SQLite。 他們說：

JDBCJobStore幾乎可以與任何數據庫一起使用，它已被Oracle，PostgreSQL，MySQL，MS SQLServer，HSQLDB和DB2廣泛使用。 要使用JDBCJobStore，必須首先創建一組數據庫表供Quartz使用。 您可以在Quartz發行版的“ docs / dbTables”目錄中找到創建表的SQL腳本。

因此，從這個問題開始：使用哪個安裝腳本來設置石英sqlite表？ 我使用derby腳本作為sqlite腳本。

問題是當我嘗試在先前插入的作業中計划觸發器時。 這是我的代碼的一部分：

// 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是這樣的：

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

我正在使用sqlite v-3.8.11.2和石英v-2.2.2。 這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$4.executeVoid(JobStoreSupport.java:1159)
    at org.quartz.impl.jdbcjobstore.JobStoreSupport$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

問題似乎是sqlite jdbc驅動程序不支持方法ResultSet.getBlob（） 。

但是，石英使用此方法來檢索分配給Job的JobDataMap 。

如果仍然想在sqlite中使用石英，則可以擴展StdJDBCDelegate並檢索/設置blob ，如此答案中所建議的那樣 。

乍一看，您似乎只必須重寫方法

1. StdJDBCDelegate.getObjectFromBlob（）和
2. StdJDBCDelegate.getJobDataFromBlob（）

由於我不確定以后是否會出現更多問題（例如，您可能會看到sqlite jdbcdriver具有更多不受支持的ResultSet方法 ），我寧願建議使用開箱即用的數據庫。

Answer 2

根據mam10eks的建議，以下代碼對我有用。

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);
  }
}

現在將以下內容放入quartz.properties

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