DeadLock in tomcat

Question

When tomcat server in production has runned for 3 or 4 days it stop responding and need to bee restarted.
When i take out a thread dump, all threads are locked on java.net.SocketInputStream.socketRead0(Native Method). In the java code it do this simple thing:
UpdateSelectedDocumentsInterceptor.java, line 39 se TP 206:
if (request.getParameter("allDocumentIdsOnPage") == null) {
We use JVM 1.5.0_06-b05, tomcat 5.5, mod_jk and apache
What is locked? Is it possible that the request parameter can be locked for reading?
"TP-Processor212" daemon prio=1 tid=0x2aed7340 nid=0x5e57 runnable [0x1d6b5000..0x1d6b5580]
at java.net.SocketInputStream.socketRead0(Native Method) at java.net.SocketInputStream.read(SocketInputStream.java:129) at java.io.BufferedInputStream.fill(BufferedInputStream.java:218) at java.io.BufferedInputStream.read1(BufferedInputStream.java:256) at java.io.BufferedInputStream.read(BufferedInputStream.java:313) - locked <
0x89ad51d8> (a java.io.BufferedInputStream) at org.apache.jk.common.ChannelSocket.read(ChannelSocket.java:607) at org.apache.jk.common.ChannelSocket.receive(ChannelSocket.java:545) at org.apache.jk.common.ChannelSocket.processConnection(ChannelSocket.java:672) at org.apache.jk.common.ChannelSocket$SocketConnection.runIt(ChannelSocket.java:876) at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:684) at java.lang.Thread.run(Thread.java:595)
"TP-Processor206" daemon prio=1 tid=0x2b6c86b0 nid=0x5dc5 runnable [0x1da3b000..0x1da3c780] at java.net.SocketInputStream.socketRead0(Native Method) at java.net.SocketInputStream.read(SocketInputStream.java:129) at java.io.BufferedInputStream.fill(BufferedInputStream.java:218) at java.io.BufferedInputStream.read1(BufferedInputStream.java:256) at java.io.BufferedInputStream.read(BufferedInputStream.java:313) - locked <
0x6b3f5a90> (a java.io.BufferedInputStream) at org.apache.jk.common.ChannelSocket.read(ChannelSocket.java:607) at org.apache.jk.common.ChannelSocket.receive(ChannelSocket.java:545) at org.apache.jk.common.JkInputStream.receive(JkInputStream.java:185) at org.apache.jk.common.JkInputStream.doRead(JkInputStream.java:164) at org.apache.coyote.Request.doRead(Request.java:418) at org.apache.catalina.connector.InputBuffer.realReadBytes(InputBuffer.java:284) at org.apache.tomcat.util.buf.ByteChunk.substract(ByteChunk.java:404) at org.apache.catalina.connector.InputBuffer.read(InputBuffer.java:299) at org.apache.catalina.connector.CoyoteInputStream.read(CoyoteInputStream.java:192) at org.apache.catalina.connector.Request.readPostBody(Request.java:2392) at org.apache.catalina.connector.Request.parseParameters(Request.java:2372) at org.apache.catalina.connector.Request.getParameter(Request.java:998) at org.apache.catalina.connector.RequestFacade.getParameter(RequestFacade.java:352) at javax.servlet.ServletRequestWrapper.getParameter(ServletRequestWrapper.java:157) at com.retriever.ui.commons.interceptor.UpdateSelectedDocumentsInterceptor.preHandle(UpdateSelectedDocumentsInterceptor.java:39)

Answer 1

This is the UpdateSelectedDocumentsInterceptor. It's the first code that thats run when people using the webapp. It is locked on if (request.getParameter(IKeys.ALL_DOCUMENT_IDS_ON_PAGE) == null), it seems that the requets.getParameter is locked because the java.net.SocketInputStream.socketRead0 is locked??
Is it possible that java.net.SocketInputStream.socketRead0 is locked. Can the SocketInputStream que be full, because to much request.
public class UpdateSelectedDocumentsInterceptor
          extends HandlerInterceptorAdapter implements ApplicationContextAware {
     // Used to lookup HttpSessionFacade objects (a new one for each client)
     private ApplicationContext applicationContext;
     // Called by container
     public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
          this.applicationContext = applicationContext;
     * Executed before performing operatins on selected documents.
     * a) get selection, b) remove old selections, c) add new selections
     * Updates list of selected documents
     public boolean preHandle(HttpServletRequest request, HttpServletResponse response,
                    Object handler) {
          // only update user selection if we are called from a 'result' page, otherwise ignore and continue
          if (request.getParameter(IKeys.ALL_DOCUMENT_IDS_ON_PAGE) == null) {
               return true;
          // GET SELECTED DOCUMENTS (SelectedDocumentS)
          // all access to users HTTP session should be through the IUserSession interface
          IHttpSessionFacade session = (IHttpSessionFacade)
                    applicationContext.getBean("httpSessionFacade");
          session.setHttpSession(request.getSession());
          LightweightSelectedDocuments selection = session.getSelectedDocuments();     
          // REMOVE OLD SELECTED DOCUMENTS FROM SELECTION, but only the one found on current page (selectedDocumentIdsOnPreviousPage)
          // Do always clear any documents present from user selection shown on the 'result'
          // page that the user comes to allow for removal of selected documents.
          // Those still selected will be re-inserted below
          // UPDATE 13.02.07: Only remove documents that doesn't exist in HttpServletRequest
          String[] selectedDocumentIds = request.getParameterValues(IKeys.SELECTED_DOCUMENT_IDS);     
          String[] selectedDocumentIdsOnPreviousPage = request.getParameter(IKeys.ALL_DOCUMENT_IDS_ON_PAGE).split(",");;
          if(selectedDocumentIds != null && request.getParameter(IKeys.ALL_DOCUMENT_IDS_ON_PAGE).length() > 0) {
               //don't remove selected documents
               for (int bigAllList = 0; bigAllList < selectedDocumentIdsOnPreviousPage.length; bigAllList++) {
                    // if not in request, remove from session
                    boolean existInRequest = false;
                    for (int smallRequestList = 0; smallRequestList < selectedDocumentIds.length; smallRequestList++) {
                         if (selectedDocumentIds[smallRequestList].equals(selectedDocumentIdsOnPreviousPage[bigAllList]))
                              existInRequest = true;
                    if (!existInRequest)
                         selection.remove(selectedDocumentIdsOnPreviousPage[bigAllList]);
          // if no documents are selected, try to remove all on page
          else if (selectedDocumentIds == null)
               selection.remove(selectedDocumentIdsOnPreviousPage);
          // ADD NEW SELECTED DOCUMENTS TO SELECTION
          // Don't update if the user selection is equal - sort order may be lost
          if(selectedDocumentIds != null && !selection.equals(selectedDocumentIds)) {
               //Service service = Service.getInstance(request.getParameter("service"));
               Service service = (Service)request.getAttribute(IKeys.SERVICE);
               for (int pos = 0; pos < selectedDocumentIds.length; pos++) {
                    // pk is only relevant in monitor section
                    long pk = RequestUtils.getLongParameter(request,
                              IKeys.DOCUMENT_PRIMARY_KEY+selectedDocumentIds[pos], -1);               
                    //only add a new selectedDocumets
                    if (!selection.isSelected(selectedDocumentIds[pos])){
                         LightweightSelectedDocument nw = new LightweightSelectedDocument(selectedDocumentIds[pos],
                                   pk != -1 ? new Long(pk) : null, service.getId());
                         selection.add(nw);
          return true; // always continue request processing
}