Answer Posted / 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);
}
}

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