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for(int cnt = 0; cnt<max; cnt++){
//do something}//end of In Java, the scope can be reduced by placing it within a block of code within the method. The scope extends from the point at which it is declared to the end of the block of code in which it is declared.
A block of code is defined by enclosing it within curly brackets as shown below
{ ... } .
The scope of a local variable extends from the point at which it is declared to the end of the block of code in which it is declared.
In Java, local variables are declared within the body of a method or constructor, or within a block of code contained within the body of a method orconstructor.
A member variable is a member of a class ( class variable) or a member of an object instantiated from that class ( instance variable). It must be declared within a class, but not within the body of a method orconstructor of the class.
The scope of a variable places it in one of the following four categories:
The scope of a Java variable is the block of code within which the variable is accessible.
The rules for Java variable names are as follows:
In Java, a legal identifier is a sequence of Unicode letters and digits of unlimited length. The first character must be a letter. All subsequentcharacters must be letters or numerals from any alphabet that Unicode supports. In addition, the underscore character ( _ ) and the dollar sign ( $ ) are considered letters and may be used as any character including the first one.
False. The name of a reference variable evaluates to either null, or to information that can be used to access an object whose reference has been storedin the variable.
Later versions of Java support either syntax shown in Listing 1 .
| Listing 1 . Listing for Answer 22. |
|---|
class test{
public static void main(String[]args){
Double var1 = 5.5;double var2 = var1.doubleValue();
System.out.println(var2);double var3 = var1;
System.out.println(var3);}//end main
}//end class test |
The proper syntax for early versions of Java is shown below. Note the upper-case D . Also note the instantiation of a new object of type Double .
Double myWrappedData = new Double(5.5); Later versions of Java support the following syntax with the new object of type Double being instantiated automatically:
Double myWrappedData = 5.5; The proper syntax is shown below. Note the lower-case d .
double myPrimitiveData = 5.5; 
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