Java Reference
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▪ Annotations (metadata; see Using and Defining Annotations )
▪ Generic Types
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static import
Java 5 foreach loop
You want a convenient means of accessing all the elements of an array or collection. The
Java 5 foreach loop syntax is as follows:
for (Type localVar : IterableOfThatType) {
...
}
For example:
for (String s : myListOfStrings) {
// use s here
}
This form of for is pronounced as “for each” and is referred to that way in the documenta-
tion and the compiler messages; the colon (:) is pronounced as “in” so that the statement is
read as “foreach String s in myListOfStrings.” The String named s will be given each value
from myListOfStrings for one pass through the loop. How is myListOfStrings declared?
The foreach construction can be used on Java arrays, on Collection classes, and on any-
thing that implements the Iterable interface. The compiler turns it into an iteration, typic-
ally using an Iterator object where Collection classes are involved. Example A-1 shows
using foreach to iterate through an array and a List .
Example A-1. ForeachDemo.java
String [] data = { "Toronto" , "Stockholm" };
for
for ( String s : data ) {
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