JAVA

java int to biginteger

// Primitive int
int myInt = 10
BigInteger bigInt = BigInteger.valueOf(myInt);
// Integer object
Integer integer = Integer.valueOf(myInt);
BigInteger bigInt = BigInteger.valueOf(myInteger.intValue());
bigInt = BigInteger.valueOf(myInteger);		// works too

java big integer to int

yourInt = yourBigInteger.intValue();