numbers - Why does java.lang.Long's .longValue() cast its (long) instance value to long? -

i have been investigating java.lang.long class source code.

consider this:

public final class long extends number implements comparable<long> {       ....       private final long value;           ....       public long longvalue() {             return (long)value;       }       .... } 

what reason cast long long?

why not reralize serialize (?) number class in case?

p.s.1 source code link

i have these possible explanations:

1. carelessness of developers
2. compliance unified code style
3. it made special case, don't understand why.

p.s.2

my java version - 1.7.0_45-b18

p.s.3 information:

integer:

public final class integer extends number implements comparable<integer> {           ....           private final int value;               ....           public int intvalue() {             return value;           }               .... } 

short:

public final class short extends number implements comparable<short> {             ....             private final short value;                 ....             public short shortvalue() {                 return value;             }             .... } 

and same byte , character. (none of these cast like-to-like.)

is problem, or may forgotten?

i have assumption made code unified related methods?

observe single code style.

 public short shortvalue() {         return (short)value;     }       public int intvalue() {         return (int)value;     }       public long longvalue() {         return (long)value;     }       public float floatvalue() {         return (float)value;     }       public double doublevalue() {         return (double)value;     } 

but noticed in java 1.6(1.6_0_45 @ least) integer class

public int intvalue() {             return (int)value; } 

but in java 1.7 integer class

public int intvalue() {             return value; } 

conclusion: developers have not paid attention aspect.

p.s. assumption only.