Bug 207250 Check blank value for datetime type parameter from url.[0002][0705]
Description: Check blank value for datetime type parameter from url. Build number:2.3.0.v20071023 Steps to reproduce: 1. New a datetime parameter mydt,listbox, tick off isRequired. 2. Preview in external browser and add "&dt=" in url, press enter. Expected result: Error message to indicate blank value isn't allowed for this parameter. Actual result: No error message and blank value is accepted. I tried to new a jsp and use <birt:paramDef> to pass the blank value and the blank value is accepted,too. Error log:n/a
viewer/org.eclipse.birt.report.viewer/birt/WEB-INF/classes/org/eclipse/birt/report/context/ViewerAttributeBean.java
* @param request
	 */
	public ViewerAttributeBean( HttpServletRequest request )
	{
		try
		{
			init( request );
		}
		catch ( Exception e )
		{
			this.exception = e;
		}
	}
	/**
	 * Init the bean.
	 * 
	 * @param request
	 * @throws Exception
	 */
	protected void __init( HttpServletRequest request ) throws Exception
	{
		
		if ( ParameterAccessor.isGetImageOperator( request )
				&& ( IBirtConstants.SERVLET_PATH_FRAMESET
						.equalsIgnoreCase( request.getServletPath( ) )
						|| IBirtConstants.SERVLET_PATH_OUTPUT
								.equalsIgnoreCase( request.getServletPath( ) )
						|| IBirtConstants.SERVLET_PATH_RUN
								.equalsIgnoreCase( request.getServletPath( ) ) || IBirtConstants.SERVLET_PATH_PREVIEW
						.equalsIgnoreCase( request.getServletPath( ) ) ) )