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General Java Questions I
this method like this:
myFunction (object); // object has method useMyMethod(){ do smth here...}
..
..
somewhere in another place where use this function..
object.useMyMethod();
What is difference capacity() and size() methods for vector?
What is difference between
public final int capacity()
Returns the current capacity of this vector.
and
public final int size()
Returns the number of components in this vector.
Answer: please read this method: ensureCapacity
public final synchronized void ensureCapacity(int minCapacity)
Increases the capacity of this vector, if necessary, to ensure that it can hold at least
the number of components specified by the minimum capacity argument.
Parameters:
minCapacity - the desired minimum capacity.
What're the differences between classpath and import in the java application?
Do I need to have the package in the classpath first before importing in a java
application or need not?
Answer: Classpath is an environment variable of your OS, you have to set it (or
better: Java sets it) to tell Java where to search for classes.
You use import in a program to let Java search for the specified classes within the
classpath. This implies that the package must be in the classpath.
--
Stephan Effelsberg
Q: What is difference between Iterator and Enumeration?
First of all Java FAQ Team wish you !!!HAPPY NEW YEAR!!! and then
Answer: from
http://java.sun.com/docs/books/tutorial/collections/interfaces/collection.html
The object returned by the iterator method deserves special mention. It is an Iterator,
which is very similar to an Enumeration, but differs in two respects:
Iterator allows the caller to remove elements from the underlying collection during the
iteration with well-defined semantics.
Method names have been improved.
The first point is important: There was no safe way to remove elements from a
collection while traversing it with an Enumeration. The semantics of this operation
were ill-defined, and differed from implementation to implementation.
The Iterator interface is shown below:
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