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Chapter 17 Using Applets As Servlet Front Ends

Listing 17.4 ShowQueries.java (continued)

  public void run() {

    while(isRunning) {

      showQueries(currentQueries);

      currentQueries = nextQueries;

      nextQueries = new QueryCollection(address, currentPage);

    }

  }

  private void showQueries(QueryCollection queryEntry) {

    // If request has been sent to server but the result

    // isn't back yet, poll every second. This should

    // happen rarely but is possible with a slow network

    // connection or an overloaded server.

    while(!queryEntry.isDone()) {

      showStatus("Waiting for data from server...");

      pause(1);

    }

    showStatus("Received data from server...");

    String[] queries = queryEntry.getQueries();

    String linefeed = "\n";

    // Put a string into TextArea every half second.

    for(int i=0; i