在網頁上顯示Quartz Scheduler詳細信息

Question

我的要求 - 顯示網頁上計劃作業的列表。

我已經完成了這麼遠

1）我初始化使用Servlet和web.xml中作出適當的條目調度。

的Servlet

public class QuartzTest extends HttpServlet implements Job { 
    public static Scheduler scheduler = null; 
    public void doGet(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException { 
    // Get details from web form and schedule a job accordingly. 
    } 
} 

2），我成功地存儲在Sybase數據庫的任務，觸發&詳細時間表。

quartz.properties

org.quartz.scheduler.instanceName = MyJobScheduler 
org.quartz.scheduler.instanceId = 1 
org.quartz.scheduler.rmi.export = false 
org.quartz.scheduler.rmi.proxy = false 

org.quartz.threadPool.class = org.quartz.simpl.SimpleThreadPool 
org.quartz.threadPool.threadCount = 5 
######################################## 
########### SYBASE CONNECTION ########## 
org.quartz.jobStore.class = org.quartz.impl.jdbcjobstore.JobStoreTX 
org.quartz.jobStore.driverDelegateClass = org.quartz.impl.jdbcjobstore.SybaseDelegate 
org.quartz.jobStore.dataSource = SybaseDS 
org.quartz.jobStore.useProperties = true 
org.quartz.dataSource.SybaseDS.driver = com.sybase.jdbc3.jdbc.SybDriver 
. 
. 
. 

我的問題我試圖呈現網頁上的調度程序的詳細信息。下面是我寫這樣做的Java類，我試圖從JSP頁面訪問這個類，但我正在逐漸NullPointerException-

我的班級

public class JSPtest { 
    // Method to get scheduler name 
    public ArrayList<String> getSchedulerName() { 
     ArrayList<String> jobList = new ArrayList<String>(); 
     String name = null; 
     try{ 
      name = QuartzTest.scheduler.getSchedulerName(); 
      jobList.add(name); 
     } 
     catch(Exception e) { 
      e.printStackTrace(); 
     } 
     return jobList; 
    } 
} 

JSP

<%! 
JSPtest jsp = new JSPtest(); 
ArrayList<String> jobList = new ArrayList<String>(); 
int count = 0; 
%> 
<% 
jobList = jsp.getSchedulerName(); 
for(count = 0; count < jobList.size(); count++){ 
    out.println("<p>"+jobList.get(count)+"</p>"); 
} 
%> 

錯誤

java.lang.NullPointerException 
    at com.globeop.quartztrials.JSPtest.getSchedulerName(JSPtest.java:32) 
    at org.apache.jsp.viewSchedule_jsp._jspService(viewSchedule_jsp.java:72) 
    at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70) 

那麼如何在網頁上顯示調度程序的詳細信息？

Answer 1

檢出jwatch它有你需要顯示的所有工作。