testmanagerbean.java

老外的在线考试

/*
 * SchoolEJB - CyberDemia's library of EJBs for educational related services.
 * Copyright (C) 2003 CyberDemia Research and Services
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Library General Public License for more details.
 * 
 * You should have received a copy of the GNU Library General Public
 * License along with this library; if not, write to the
 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA  02111-1307, USA.
 *
 * See the COPYING file located in the top-level-directory of
 * the archive of this library for complete text of license.
 */
package com.cyberdemia.school.impl;
import javax.ejb.*;
import javax.naming.*;
import java.util.*;
import com.cyberdemia.school.*;
import java.util.logging.*;

/**
* TestManagerBean is a session bean facade that provides
* useful methods for managing tests.
*
* @author Alexander Yap
*/
public class TestManagerBean implements SessionBean
{
	public TestManagerBean()
	{
		try
		{
			Context ctx = new InitialContext();
			m_testHome = (LocalTestHome)ctx.lookup("java:comp/env/ejb/localTest");
			m_quesHome = (LocalQuestionHome)ctx.lookup("java:comp/env/ejb/localQuestion");
			m_userTestAssocHome = (LocalUserTestAssocHome)ctx.lookup("java:comp/env/ejb/localUserTestAssoc");
			m_answerHistoryRecordHome =  (LocalAnswerHistoryRecordHome)ctx.lookup("java:comp/env/ejb/localAnswerHistoryRecord");
		}
		catch (NamingException nex)
		{
			throw SchoolUtils.convertToEJBException(nex);
		}
	}
	
	/**
	 * Adds a new test to the database.
	 * @param name Test name
	 * @param ownerHierId Owner hierarchy ID.
	 * @param passPercentage Passing percentage, between 0 and 100
	 * @param timeLimitSecs Time limit in seconds
	 * @param multiQuesMode true to enable multi-questions mode, false to disable it
	 * @param suppressQuesFeedback true to suppress question result feedback, false to allow it
	 * @param suppressTestEndFeedback true to suppress test results feedback, false to allow it.
	 * @return Unique ID of the new test.
	 * @throws EJBException if there is a problem creating the test.
	 */
	public String addTest(String name, String ownerHierId, double passPercentage, 
		int timeLimitSecs, boolean multiQuesMode, boolean suppressQuesFeedback,
		boolean suppressTestEndFeedback)
	{
		s_logger.log( Level.INFO, "Creating new Test name="+name+", owner="+ownerHierId+", passPercentage="+passPercentage);
		String id = null;
		try
		{
			LocalTest test = m_testHome.create(name, ownerHierId, passPercentage, timeLimitSecs, multiQuesMode, suppressQuesFeedback, suppressTestEndFeedback);
			id = test.getId();
		}
		catch (CreateException cex)
		{
			s_logger.log( Level.SEVERE, "Error creating Test "+name, cex);
			throw SchoolUtils.convertToEJBException(cex);
		}
		s_logger.log( Level.FINE, "Test with ID "+id+" successfully created.");
		return id;
	}

	/**
	 * Deactives the specified test, after which it may be considered to 
	 * be logically removed from the system.
	 * This method may perform some checks first to ensure that the test
	 * can be safely deactivated.
	 * 
	 * @param id Test ID
	 * @return true if the test is deactivated, false if it is not (either a problem or it is already inactive) 
	 * @throws EJBException if the test can't be found.
	 */		 
	public boolean deactivateTest(String id)
	{
		boolean success = false;
		try
		{
			LocalTest test = m_testHome.findByPrimaryKey(id);
			if (canDeactivateTest(test))
			{
				success = test.deactivate();
				test.setLastModifiedMillis(System.currentTimeMillis());
				if (success)
				{
					// Remove all existing questions from this Test
					test.removeAllQuestions();
					Iterator relatedQuesIter = m_quesHome.findByTest(id).iterator();
					while (relatedQuesIter.hasNext())
					{
						LocalQuestion relatedQues = (LocalQuestion)relatedQuesIter.next();
						relatedQues.setTestId("");
					}
				}
			}
		}
		catch (FinderException fex)
		{
			throw SchoolUtils.convertToEJBException(fex);
		}
		return success;
	}
	
	/**
	 * Gets list of tests belonging to a specified owner hierarchy ID.
	 * @param ownerHierId Owner hierarchy ID, or null to ignore the hierarchy ID.
	 * @param activeOnly true to only return active tests, false to return all tests.
	 * @return Array of TestData instances.
	 */
	public TestData[] getTests(String ownerHierId, boolean activeOnly)
	{
		TestData[] testDataArr = null;
		try
		{
			Iterator testIter = activeOnly ? m_testHome.findAllActive().iterator() : m_testHome.findAll().iterator();
			ArrayList testDataList = new ArrayList();
			while (testIter.hasNext())
			{
				LocalTest test = (LocalTest)testIter.next();
				if (ownerHierId!=null)
				{
					if ( ownerHierId.equals(test.getOwnerHierarchyId()) )
					{
						testDataList.add( getDataFromTest(test) );
					}
				}
				else
				{
					testDataList.add( getDataFromTest(test) );
				}
			}
			testDataArr = (TestData[])testDataList.toArray(new TestData[0]);
		}
		catch (FinderException fex)
		{
			throw SchoolUtils.convertToEJBException(fex);
		}
		return testDataArr;
	}
	
	/**
	 * Gets active tests assigned to a specified user.
	 * @param ownerHierId Owner hierarchy ID to filter tests, or null to ignore the hierarchy ID.
	 * @param userId User ID to search for.
	 * @return Array of TestData instances.
	 */
	public TestData[] getTestsForUser(String ownerHierId, String userId)
	{
		TestData[] testDataArr = null;
		try
		{
			Iterator assocIter = m_userTestAssocHome.findByUser(userId).iterator();
			ArrayList testDataList = new ArrayList();
			while (assocIter.hasNext())
			{
				LocalUserTestAssoc assoc= (LocalUserTestAssoc)assocIter.next();
				String testId = assoc.getTestId();
				LocalTest test = m_testHome.findByPrimaryKey(testId);
				if (ownerHierId!=null)
				{
					if ( ownerHierId.equals(test.getOwnerHierarchyId()) )
					{
						testDataList.add( getDataFromTest(test) );
					}
				}
				else
				{
					testDataList.add( getDataFromTest(test) );
				}
			}
			
			testDataArr = (TestData[])testDataList.toArray(new TestData[0]);
		}
		catch (FinderException fex)
		{
			throw SchoolUtils.convertToEJBException(fex);
		}
		return testDataArr;
	}
	
	/**
	 * Gets active tests that are <b>not</b> assigned to a specified user.
	 * @param ownerHierId Owner hierarchy ID to filter tests, or null to ignore the hierarchy ID.
	 * @param userId User ID to exclude.
	 * @return Array of TestData instances.
	 */
	public TestData[] getTestsForNotUser(String ownerHierId, String userId)
	{
		TestData[] testDataArr = null;
		try
		{
			Iterator testIter = m_testHome.findAllActive().iterator();
			Iterator assocIter = m_userTestAssocHome.findByUser(userId).iterator();
			Set assocIdSet = new HashSet();
			while(assocIter.hasNext())
			{
				assocIdSet.add( ((LocalUserTestAssoc)assocIter.next()).getTestId() );
			}

			ArrayList testDataList = new ArrayList();
			while (testIter.hasNext())
			{
				LocalTest test= (LocalTest)testIter.next();
				if (!assocIdSet.contains(test.getId()))
				{
					testDataList.add( getDataFromTest(test) );
				}
			}
			
			testDataArr = (TestData[])testDataList.toArray(new TestData[0]);
		}
		catch (FinderException fex)
		{
			throw SchoolUtils.convertToEJBException(fex);
		}
		return testDataArr;
	}
	
	/**
	 * Adds a question to a test. Both question and test must exist and be active.
	 * @param testId Test ID
	 * @param quesId Question ID
	 * @throws EJBException if either test or question is missing or inactive.
	 */	
	public void addQuestionToTest( String testId, String quesId)
	{
		try
		{
			LocalTest test = m_testHome.findByPrimaryKey(testId);
			LocalQuestion ques = m_quesHome.findByPrimaryKey(quesId);
			// Client code should prevent this method from being called
			// if either the test or question is inactive.
			if (!test.isActive())
			{
				throw new EJBException("Cannot add Question "+quesId+" to inactive Test "+testId);
			}
			if (!ques.isActive())
			{
				throw new EJBException("Cannot add inactive Question "+quesId+" to Test "+testId);
			}
			
			ques.setTestId(testId);
			test.addQuestion(ques);
			test.setLastModifiedMillis(System.currentTimeMillis());
		}
		catch (FinderException fex)
		{
			throw SchoolUtils.convertToEJBException(fex);
		}
	}
	
	/**
	 * Removes a question from a test. Both question and test must exist.
	 * @param testId Test ID
	 * @param quesId Question ID
	 * @throws EJBException if either test or question is missing.
	 */	
	public void removeQuestionFromTest( String testId, String quesId)
	{
		try
		{
			LocalTest test = m_testHome.findByPrimaryKey(testId);
			LocalQuestion ques = m_quesHome.findByPrimaryKey(quesId);
			test.removeQuestion(ques);
			ques.setTestId("");
			test.setLastModifiedMillis(System.currentTimeMillis());
		}
		catch (FinderException fex)
		{
			throw SchoolUtils.convertToEJBException(fex);
		}
	}
	
	/**
	 * Gets data of resources (questions) for a test.
	 * @param testId Test ID.
	 * @param count Maximum number of resources to retrieve.
	 * @return Array of ResourceListData instances.
	 * @throws EJBException if test is missing.
	 */
	public ResourceListData[] getResourcesDataFromTest( String testId, int count)
	{
		ResourceListData[] resources = null;
		try
		{
			LocalTest test = m_testHome.findByPrimaryKey(testId);
			List resourceList = test.getQuestions(count);
			resources = new ResourceListData[ resourceList.size() ];
			Iterator resourceIter = resourceList.iterator();
			for (int ridx=0; resourceIter.hasNext() && (ridx<resources.length); ridx++)
			{
				LocalQuestion ques = (LocalQuestion)resourceIter.next();
				resources[ridx] = new ResourceListData( ques.getId(), ques.getName() );
			}
		}
		catch (FinderException fex)
		{
			s_logger.log( Level.SEVERE, "Error finding Test ID="+testId, fex);
			throw SchoolUtils.convertToEJBException(fex);
		}
		catch (RuntimeException ex)
		{
			s_logger.log( Level.SEVERE, "Error getting resources data for Test ID="+testId, ex);			
			throw ex;
		}
		return resources;
	}
				
	/**
	 * Gets data of a test.
	 * @param id Test ID.
	 * @return TestData instance storing the test's data.
	 * @throws EJBException if test is missing.
	 */
	public TestData getTestData(String id) 
	{
		TestData data = null;
		try
		{
			LocalTest test = m_testHome.findByPrimaryKey(id);
			data = getDataFromTest(test);
		}
		catch (FinderException fex)
		{
			s_logger.log( Level.SEVERE, "Error finding Test ID="+id, fex);
			throw SchoolUtils.convertToEJBException(fex);
		}
		catch (RuntimeException ex)
		{
			s_logger.log( Level.SEVERE, "Error getting data for Test ID="+id, ex);			
			throw ex;
		}
		return data;
	}

	/**
	 * Updates the data of an existing test.
	 * @param id Test ID.
	 * @param data TestData instance with the test's data.
	 * @throws EJBException if test is missing
	 * @throws RuntimeException if there is a problem updating the test.
	 */
	public void setTestData(String id, TestData data) 
	{
		try