Bug 155496 Due to inactivity, a group report gives NULL Pointer Exception on selection of TOC and Export CSV option
Steps to reproduce this issue:- 1. Access any Group report that lists groups in TOC 2. For some time do not do any activity on report page (say 15 mins.) 3. Now click on Toggle Table Contents Link 4. The pop window gets opened with following error message java.lang.NullPointerException org.apache.axis.AxisFault.makeFault(AxisFault.java:101) org.eclipse.birt.report.soapengine.processor.AbstractBaseComponentProcessor.process(Unknown Source) org.eclipse.birt.report.soapengine.endpoint.BirtSoapBindingImpl.getUpdatedObjects(Unknown Source) sun.reflect.GeneratedMethodAccessor80.invoke(Unknown Source) When page remains idle for some time the same error gets displayed on selection of Export CSV option. Note:- This issue occurs for the reports that are run using '__overwrite' option. Any help on this is highly appreciated.
viewer/org.eclipse.birt.report.viewer/birt/WEB-INF/classes/org/eclipse/birt/report/utility/ParameterAccessor.java
/**
	 * Custom request headers to identify the request is a normal HTTP request
	 * or a soap request by AJAX.
	 */
	public static final String HEADER_REQUEST_TYPE = "request-type"; 
	/**
	 * The request type of "soap".
	 */
	public static final String HEADER_REQUEST_TYPE_SOAP = "soap"; 
	/**
	 * Parameter name that gives the IID of the export data form.
	 */
	public static final String PARAM_IID = "iid"; 
	/**
	 * Parameter name that gives the result set names of the export data form.
	 */
	public static final String PARAM_RESULTSETNAME = "ResultSetName"; 
	/**
	 * Parameter name that gives the selected column numbers of the export data
	 * form.
	 */
	public static final String PARAM_SELECTEDCOLUMNNUMBER = "SelectedColumnNumber"; 
	/**
	 * Parameter name that gives the selected column names of the export data
	 * form.
	 */
	public static final String PARAM_SELECTEDCOLUMN = "SelectedColumn"; 
	/**
	 * Servlet parameter name that gives the default locale of the BIRT viewer.
	 */