please tell me what is wrapper class in java with example ?
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Answer / vikneswarank
its a class used to convert primitive data type to user
defined data type like Integer
for example
public class WrapperSample1
{
public static void main (String args[])
{
int iVal = 100;
long lVal = 200;
float fVal = 300;
double dVal = 400;
String str = "123";
//primitive types to corresponding wrapper objects
Integer intVal = Integer.valueOf(iVal);
Long lgVal = Long.valueOf(lVal);
Double dbVal = Double.valueOf(dVal);
Float ftVal = Float.valueOf(fVal);
//primitive types to string objects
str = String.valueOf(iVal);
str = String.valueOf(lVal);
str = String.valueOf(fVal);
str = String.valueOf(dVal);
//wrapper Objects to corresponding primitive types
iVal = intVal.intValue();
lVal = lgVal.longValue();
fVal = ftVal.floatValue();
dVal = dbVal.doubleValue();
//String to primitive types
iVal = Integer.parseInt(str);
lVal = Long.parseLong(str);
fVal = Float.parseFloat(str);
dVal = Double.parseDouble(str);
//string to wrapper objects
intVal = Integer.valueOf(str);
lgVal = Long.valueOf(str);
ftVal = Float.valueOf(str);
dbVal = Double.valueOf(str);
}
}
| Is This Answer Correct ? | 60 Yes | 17 No |
Answer / naresh tuhania
By the help of Wrapper classes we can convert a primitive
type into Object type . These are the static classes and
provides methods for this .
| Is This Answer Correct ? | 41 Yes | 7 No |
Answer / srinu
The wrapper class used for To convert Primitive data Type
in to User defined data Type and also Collection class
contain all user defined data type this user defined data
type convert into primitive data type
| Is This Answer Correct ? | 22 Yes | 8 No |
Answer / pradeep
the wrapper class is used for accessing the primtive data
type for to the object.
| Is This Answer Correct ? | 16 Yes | 3 No |
Answer / ankur tyagi
The wrapper class used for To convert Primitive data Type
in to User defined data Type.
| Is This Answer Correct ? | 7 Yes | 0 No |
for each and every fundamental datatype theire exist predefined class.such predefined called wrapper class.the perpose of wrapper class is that converting numerical string data into fundamental data
| Is This Answer Correct ? | 0 Yes | 0 No |
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