Lalchand omprakash

I include a JPanel with a null layout in a JScrollPane, and it doesn't display the scrollbars. Why?

but its working with layout manager

public static void main(String[] args) { JFrame frame = new JFrame(); JPanel panel = new JPanel(); panel.setLayout(new BoxLayout(panel, BoxLayout.PAGE_AXIS)); for(int i = 0; i < 20; i++) { panel.add(new JButton("Button " + i)); } //Creating JScrollPane with JPanel JScrollPane scrollPane = new JScrollPane(panel); JPanel otherPanel = new JPanel(); otherPanel.setLayout(new BorderLayout()); //Adding scrollPane to panel otherPanel.add(scrollPane); frame.add(otherPanel); frame.setSize(200,200); frame.setVisible(true); }

I am having approximately 150 web applications in my tomcat web-apps directory can these be the one of the reason for increase in memory usage. i have installed tomcat as a service.
But also I am using only one web application rest of them(149) are just the back up of the one, is these causes memory issues

i want to know whether one session id for one IP address or for one browser instance ?

i opened my jsp application in three browser windows its creates three different session ids?
suppose i want to use a single session for multiple instance of browser is it possible or not.

may i know the reason why a class in Java can't be declared as private or protected?

yeah i have used the Hash map for the purpose of reading,writing the data. i have placed the hash map in "<% %>" scriplet along with code that will iterate over the collection. i think due to multiple request to the jsp page data race occurring in the jsp. i have tried synchronization is there any other way to avoid the data race problem.

In my jsp page I am having a Hash Map collection, when multiple request made to the jsp page the operation of Hash map is unpredictable. but when i replaced the Hash Map with string array every thing is working fine(execution in a synchronized manner). may i know the reason why execution of hash map during multiple request is unpredictable? is there any possibility of synchronizing the hash map

eclipse IDE

Does anyone understand what this error means?? Is produced when trying to
save a jsp



"Save Failed:Attempted to beginRule: P/WRS-d0ipc02, does not match outer
scope rule:

when i invoke t.run() method the corresponding method in mythread class get excuted but the thread is runned by a thread
named main , not by lal which i have given the name to the thread .

class mythread implements Runnable { public void run() { for(int i=1;i<5;i++) { System.out.println("RUN BY "+Thread.currentThread().getName()+" i "+i+" id "+Thread.currentThread().getId()); } } } class t { public static void main(String args[]) { mythread r=new mythread(); Thread t=new Thread(r); t.setName("lal"); t.run(); t.start(); } }

The output that i have got is

RUN BY main i 1 id 1
RUN BY main i 2 id 1
RUN BY main i 3 id 1
RUN BY main i 4 id 1
RUN BY lal i 1 id 8
RUN BY lal i 2 id 8
RUN BY lal i 3 id 8
RUN BY lal i 4 id 8


forgive me if the doubt is silly one

i have planning to take scjp exam. but i am confused to take whether scjp 5 or scjp 6.

Any suggestion please.

Thanks.

congrates...

Congratulations