Whatever happened to implicit conversions?

Question

Java 6, with implicit "packaging" conversions:
class  JE {
  JE( short x) {
        // blah
class JN  {
    JN ( Short ... a ) {
        for( Short s : a )
         coll.add( new JE( s ) );
new JN( 112,113,114,115 ) ); // <<<---  "The constructor JN( int, int, int, int) is undefined"???
Does the code imply a "jump shift" (i.e. int to Short) that isn't going to work? The language spec says that a numeric literal such as 1 is either a int or a short, depending on the context. Well, this looks like context.

Answer 1

DMF. wrote:
new JN( 112,113,114,115 ) ); // <<<--- "The constructor JN( int, int, int, int) is undefined"Well, yeah, those are ints, not shorts. Always has been that way. Autoboxing and varags have nothing to do with it.
import java.net.*;
public class Z {
  Z(short s1, short s2, short s3, short s4) {}
  public static void main(String[] args) {
    new Z(1, 2, 3, 4);
:; javac Z.java
Z.java:7: cannot find symbol
symbol  : constructor Z(int,int,int,int)
location: class Z
    new Z(1, 2, 3, 4);
    ^This behavior has been part of Java as long as I've been working with it.
Does the code imply a "jump shift" (i.e. int to Short) that isn't going to work? The language spec says that a numeric literal such as 1 is either a int or a short, depending on the context. Well, this looks like context.The JLS states a lot more details about how and when conversions occur, and this simply isn't one of those cases, nor has it ever been as far as I know.
The expression 1 is and always has been of type int. Period. Java does not support automatic conversion of int to short in the following:
import java.net.*;
public class Z {
    static int x;
    static int y;
    static int z;
    static int w;
  Z(short s1, short s2, short s3, short s4) {}
  public static void main(String[] args) {
    new Z(x, y, z, w);
}and the situation you present is identical to this one.
Edited by: jverd on Aug 8, 2010 1:47 AM