1.what is a transient variable?
A transient variable could be a variable that will not be serialized.
2.which containers use a border Layout as their default layout?
The window, Frame and Dialog categories use a border layout as their default layout.
3.Why do threads block on I/O?
Threads block on i/o (that is enters the waiting state) in order that different threads could execute whereas the i/o
Operation is performed.
4. however square measure Observer and evident used?
Objects that taxon the evident category maintain an inventory of observers. once Associate in Nursing evident object is
updated it invokes the update() technique of every of its observers to advise the observers that it's modified
state. The Observer interface is enforced by objects that observe evident objects.
5. what's synchronization and why is it important?
With relevancy multithreading, synchronization is that the capability to regulate the access of multiple threads to
shared resources. while not synchronization, it's doable for one thread to switch a shared object whereas
another thread is within the method of victimization or change that object's worth. This usually results in important
errors.
6. will a lock be nonheritable on a class?
Yes, a lock are often nonheritable on a category. This lock is nonheritable on the class's category object.
7. what is new with the stop(), suspend() and resume() ways in JDK one.2?
The stop(), suspend() and resume() ways are deprecated in JDK one.2.
8. Is null a keyword?
The null worth isn't a keyword.
9. what's the popular size of a component?
the popular size of a part is that the minimum part size which will enable the part to show
normally.
10. What technique is employed to specify a container's layout?
The setLayout() technique is employed to specify a container's layout.
11. that containers use a FlowLayout as their default layout?
The Panel and application program categories use the FlowLayout as their default layout.
12. What state will a thread enter once it terminates its processing?
once a thread terminates its process, it enters the dead state.
13. what's the Collections API?
The Collections API could be a set of categories and interfaces that support operations on collections of objects.
14. that characters is also used because the second character of Associate in Nursing symbol, however not because the 1st
character of Associate in Nursing identifier?
The digits zero through nine might not be used because the 1st character of Associate in Nursing symbol however they'll be used once the
1st character of Associate in Nursing symbol.
15. what's the List interface?
The List interface provides support for ordered collections of objects.
16. however will Java handle number overflows and underflows?
It uses those low order bytes of the result which will work into the scale of the kind allowed by the operation.
17. what's the Vector class?
The Vector category provides the aptitude to implement a growable array of objects
18. What modifiers is also used with Associate in Nursing inner category that's a member of Associate in Nursing outer class?
A (non-local) inner category is also declared as public, protected, private, static, final, or abstract.
19. what's Associate in Nursing Iterator interface?
The Iterator interface is employed to step through the weather of a set.
20. what's the distinction between the >> and >>> operators?
The >> operator carries the sign bit once shifting right. The >>> zero-fills bits that are shifted out.
21. that technique of the part category is employed to line the position and size of a component?
setBounds()
22. what number bits square measure wont to represent Unicode, ASCII, UTF-16, and UTF-8 characters?
Unicode needs sixteen bits and computer code need seven bits. though the graphic symbol set uses solely seven bits, it is
sometimes diagrammatic as eight bits. UTF-8 represents characters victimization eight, 16, and eighteen bit patterns. UTF-16 uses 16-bit and bigger bit patterns.
23. What is that the distinction between yielding and sleeping?
once a task invokes its yield() technique, it returns to the prepared state. once a task invokes its sleep()
method, it returns to the waiting state.
24. Which java.util categories and interfaces support event handling?
The EventObject category and therefore the EventListener interface support event process.
25. Is sizeof a keyword?
The sizeof operator isn't a keyword.
26. What square measure wrapped classes?
Wrapped categories square measure categories that enable primitive varieties to be accessed as objects.
27. will pickup guarantee that a program won't run out of memory?
pickup doesn't guarantee that a program won't run out of memory. it's doable for
programs to dissipate memory resources quicker than they're garbage collected. it's conjointly doable for
programs to form objects that aren't subject to pickup
28. What restrictions square measure placed on the placement of a package statement inside a ASCII text file file?
A package statement should seem because the 1st line during a ASCII text file file (excluding blank lines and
comments).
29. will Associate in Nursing object's finalize() technique be invoked whereas it's reachable?
Associate in Nursing object's finalize() technique can not be invoked by the rubbish collector whereas the item remains accessible.
However, Associate in Nursing object's finalize() technique is also invoked by different objects.
30. what's the immediate taxonomic group of the application program class?
Panel
31. what's the distinction between preventive planning and time slicing?
Under preventive planning, the very best priority task executes till it enters the waiting or dead states or
the next priority task comes into existence. underneath time slicing, a task executes for a predefined slice of
time and so reenters the pool of prepared tasks. The computer hardware then determines that task ought to execute
next, supported priority and different factors.
32. Name 3 part subclasses that support painting.
The Canvas, Frame, Panel, and application program categories support painting.
33. What worth will readLine() come back once it's reached the tip of a file?
The readLine() technique returns null once it's reached the tip of a file.
34. what's the immediate taxonomic group of the Dialog class?
Window
35. what's clipping?
Clipping is that the method of confining paint operations to a restricted space or form.
36. what's a native method?
A native technique could be a technique that's enforced during a language apart from Java.
37. will a for statement loop indefinitely?
Yes, a for statement will loop indefinitely. for instance, contemplate the following:
for(;;) ;
38. What square measure order of precedence and associativity, and the way square measure they used?
Order of precedence determines the order within which operators square measure evaluated in expressions. Associatity
determines whether or not Associate in Nursing expression is evaluated left-to-right or right-to-left
39. once a thread blocks on I/O, what state will it enter?
A thread enters the waiting state once it blocks on I/O.
40. To what worth could be a variable of the String sort mechanically initialized?
The default worth of Associate in Nursing String sort is null.
41. what's the catch or declare rule for technique declarations?
If a checked exception is also thrown inside the body of a way, the tactic should either catch the
exception or declare it in its throws clause.
42. what's the distinction between a MenuItem and a CheckboxMenuItem?
The CheckboxMenuItem category extends the MenuItem category to support a menu item that will be checked or
unchecked.
43. what's a task's priority and the way is it employed in scheduling?
A task's priority is Associate in Nursing number worth that identifies the relative order within which it ought to be dead with relevancy different tasks. The computer hardware tries to schedule higher priority tasks before lower priority tasks.
44. What category is that the prime of the AWT event hierarchy?
The java.awt.AWTEvent category is that the highest-level category within the AWT event-class hierarchy.
45. once a thread is made and commenced, what's its initial state?
A thread is within the prepared state once it's been created and commenced.
46. will Associate in Nursing Associate in Nursingonymous category be declared as implementing an interface and lengthening a class?
Associate in Nursing Associate in Nursingonymous category could implement an interface or extend a taxonomic group, however might not be declared to try and do both.
47. what's the vary of the short type?
The vary of the short sort is -(2^15) to 2^15 - one.
48. what's the vary of the char type?
The vary of the char sort is zero to 2^16 - one.
49. within which package square measure most of the AWT events that support the event-delegation model defined?
Most of the AWT-related events of the event-delegation model square measure outlined within the java.awt.event package.
The AWTEvent category is outlined within the java.awt package.
50. what's the immediate taxonomic group of Menu?
MenuItem
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