Errata - Sybex 829 - Chapter 9

[João Lopes]

Hi,

I think there is an errata on Chapter 9, on pages 483/484. (Map.of() and Map.CopyOf() explanation):

there is a factory method to create a Map. You pass any number of pairs of keys and values.

 Map.of("key1", "value1", "key2", "value2");

This isn't true, Map.of() only accepts maximum of 10 keys and values pairs.

Map also provides a method that lets you supply key/value pairs.

 Map.ofEntries(
   Map.entry("key1", "value1"),
   Map.entry("key2", "value2"));

Now we can't forget to pass a value. If we leave out a parameter, the entry() method won't compile.

On the Map.of() if we forget to pass a value, the method won't compile either.

Thanks,
João

[Jeanne Boyarsky]

Confirmed and added to erratas This is another one that was wrong in the Java 11 book without anyone noticing. Have another cow!