Confusion about statics

Hello,
Even though, we can use static variables in non-static methods , we are not allowed to use non-static variables in static methods. So Why??
Please expalin...

Even though, we can use static variables in
non-static methods , we are not allowed to use
e non-static variables in static methods. So Why??
Please expalin...A static variable "lives" in the static environment of the class. A non-static variable lives in the environment of an object. The latter could be a called a dynamic variable but it normally isn't.
You actually can access a non-static variable (the dynamic environment of an object) from a static method (the static environment of the class) if you have a reference to the object.

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Confused about static thread safe.help me

sample codes look like follows:
public static class test
public static method1(Object obj)
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Thread safety isn't about methods and it isn't about static. It's about being carefully about access to resources which may be accessed by more than one thread, and in particular may be changed by one thread and accessed by another.
Local variables are always thread safe, and there's no problem about serveral threads executing the same block of code concurently.
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If I have
public class abc
private static final int x=1;
public static def()
final int y=2;
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1. static methods are faster as there is no
polymorphismActually there is polymorphism from a Class P.O.V.
2. it's nice for helper classes like java.lang.Math
who have no instances.
3. They are needed for Objects without public
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Confusion about TreeMap

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I'm currently studying for SCJP exam and am confused about the following code.
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From the API:
headMap
public NavigableMap<K,V> headMap(K toKey,
boolean inclusive)
Description copied from interface: NavigableMap
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Hi all,
I have an customersBean which is inherit from customersRemote and my problem is i' am little confuse about injecting the entity(customer).
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this is inside on EJB...............
public class CustomersBean implements com.savingsaccount.session.CustomersRemote {
@PersistenceContext(unitName="SavingAccounts")
EntityManagerFactory emf;
EntityManager em;
/** Creates a new instance of CustomersBean */
public CustomersBean() {
public void create(int id, String name, String address, String telno, String mobileno)
try{
//This is the entity.
Customer _customer = new Customer();
_customer.setId(id);
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_customer.setAddress(address.toString());
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_customer.setMobileno(mobileno.toString());
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michael.

http://www.oracle.com/technology/documentation/berkeley-db/je/TransactionGettingStarted/chkpoint.html
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I'll get this eventually =)

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VD

is it really possible that we can install standby and primary on same host??
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In a few words -- no. Try here:
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Hi,
I am confuse about passing by reference and passing by value. I though objects are always passed by reference. But I find out that its true for java.sql.PreparedStatement but not for java.lang.String. How come when both are objects?
Thanks

Hi,
I am confuse about passing by reference and passing
by value. I though objects are always passed by
reference. But I find out that its true for
java.sql.PreparedStatement but not for
java.lang.String. How come when both are objects?
ThanksPass by value implies that the actual parameter is copied and that copy is used as the formal parameter (that is, the method is operating on a copy of what was passed in)
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Lee
PS: I will venture a guess that this is the 3rd reply. Let's see...
Ok, second. Close enough.
Yeah, good on yer mlk, At least I beat Jos.
Message was edited by:
tsith

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psedbtool version 1.07
Opening catalog C:\Documents and Settings\All Users\Application Data\Adobe\Photoshop Elements\Catalogs\Moms pics\catalog.pse7db
Photoshop Elements version:      7
Total files               :   4833
Total files missing       :      0
Total files offline       :    278
Total files wrong volume :      0
****** Volumes with warnings: 1
PSE Volume Table
Path used by PSE        : F:
Type                    : builtin_drive
Status                  : online
Total files             : 0
Total files missing     : 0
Total files wrong volume: 0
Description             : MEDIA
Serial                  : 1C2F-9805
Drive_path_if_builtin   : F:
Id                      : 32520
Path used by PSE        : M:
Type                    : builtin_drive
Status                  : online
Total files             : 938
Total files missing     : 0
Total files wrong volume: 0
Description             : FreeAgent Drive
Serial                  : 7830-2970
Drive_path_if_builtin   : M:
Id                      : 93626
Path used by PSE        : E:
Type                    : builtin_drive
Status                  : online
Total files             : 0
Total files missing     : 0
Total files wrong volume: 0
Description             : GAMES
Serial                  : 025A-4B70
Drive_path_if_builtin   : E:
Id                      : 93625
Path used by PSE        : L:
Type                    : builtin_drive
Status                  : online
Total files             : 114
Total files missing     : 0
Total files wrong volume: 0
Description             : FreeAgent Drive
Serial                  : 60AE-A816
Drive_path_if_builtin   : K:
Id                      : 31354
***** WARNING *****     : Wrong drive letter in catalog
Path used by PSE        : \\dmzhost\media
Type                    : network_drive
Status                  : offline
Total files             : 278
Total files missing     : 0
Total files wrong volume: 0
Description             : //dmzhost/media
Serial                  : //dmzhost/media
Drive_path_if_builtin   :
Id                      : 26948
Path used by PSE        : J:
Type                    : builtin_drive
Status                  : online
Total files             : 3503
Total files missing     : 0
Total files wrong volume: 0
Description             : MEDIA2
Serial                  : BAC0-B5A3
Drive_path_if_builtin   : J:
Id                      : 108
Path used by PSE        : C:\Documents and Settings\All Users\Application Data\Adobe\Photoshop Elements\Catalogs\Moms pics
Type                    : database_relative_drive
Status                  : online
Total files             : 0
Total files missing     : 0
Total files wrong volume: 0
Description             : database relative
Serial                  : amoc:database_relative_volume
Drive_path_if_builtin   :
Id                      : 2
Windows Drives
Drive Type             Serial     Path
A:     removable_drive 0000-0000
C:     builtin_drive    9088-07F9
D:     builtin_drive    F408-1CB0
E:     builtin_drive    025A-4B70
F:     builtin_drive    1C2F-9805
G:     builtin_drive    242D-15ED
H:     readonly_drive   0000-0000
I:     builtin_drive    427D-3F6B
J:     builtin_drive    BAC0-B5A3
K:     builtin_drive    64E8-9846
L:     builtin_drive    60AE-A816
M:     builtin_drive    7830-2970
Thanks so much for your help!
Jim

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