SCJP: Rules #Java Short Notes #SCJP

A class's superclasses don't have to implement Serializable in order to be serialized
if a superclass doesn't implement Serializable then it's constructor will run during deserialization
A transient variable's state is lost during serialization, but a volatile variable's state is not lost
Java:Volatile variable
Transient Variable
NumberFormat, Calendar, DateFormat are abstract classes. Use the getInstance method to get NumberFormat instances.
The + quantifier in a regular expression indicates 1 or more occurrences, * indicates 0 or more, [] just one character in the group, () indicates a whole group match.
The default separator in Scanner class is a blank NOT a comma
Multiple threads can be created using the same Runnable object, but a given thread can be started only once.
Thread.yield(): Causes the currently executing thread object to temporarily pause and allow other threads to execute.
Thread.join(): Waits for this thread to die.
Wait(), Notify(), NotifyAll() methods
Low coupling: classes know the least possible about each other, is preferable over tight coupling.
High cohesion: Each class has well focused responsibilities. Is preferable over low cohesion.
Polymorphism does NOT apply to static methods.
Instance variable cannot be referenced from static method

From: http://sitestree.com/?p=4883
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Post Data:2011-09-04 06:32:26

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