Returns a {@code Long} instance representing the specified
{@code long} value.
If a new {@code Long} instance is not required, this method
should generally be used in preference to the constructor
{@link #Long(long)}, as this method is likely to yield
significantly better space and time performance by caching
frequently requested values.
Note that unlike the {@linkplain Integer#valueOf(int)
corresponding method} in the {@code Integer} class, this method
is <em>not</em> required to cache values within a particular
range.
@param l a long value.
@return a {@code Long} instance representing {@code l}.
Returns a {@code Long} instance representing the specified {@code long} value. If a new {@code Long} instance is not required, this method should generally be used in preference to the constructor {@link #Long(long)}, as this method is likely to yield significantly better space and time performance by caching frequently requested values.
Note that unlike the {@linkplain Integer#valueOf(int) corresponding method} in the {@code Integer} class, this method is <em>not</em> required to cache values within a particular range.
@param l a long value. @return a {@code Long} instance representing {@code l}.