Writing Scripts in Nashorn - Scripting in Java: Integrating with Groovy and JavaScript - page 75

Using the while statement...
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Using the do-while statement...
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Using the for statement...
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The for..in statement is used to iterate over indices of arrays or property names of
objects. It can be used with collections such as arrays, lists, maps, any Nashorn objects,
and so on. Its syntax is:
for(var index in object)
Statement;
First, the object is evaluated. If it evaluates to null or undefined , the entire for..
in statement is skipped. If it evaluates to an object, the statement assigns the enumerable
property to the index and executes the body. The index is of the string type. In case
of an array, the index is the index of the array element as a string. In case of any other
collections such as a list or a map (a Nashorn object is also a map), the property of the
object is assigned to index . You can use the bracket notation ( object[index] ) to access
the value of the property. The following code demonstrates how to use the for..in
statement to iterate over the indices of an array:
// Create an array of three strings
var empNames = ["Ken", "Fred", "Li"];
// Use the for..in statement to iterate over indices of the array
for(var index in empNames) {
var empName = empNames[index];
printf("empNames[%s]=%s", index, empName);
}
empNames[0]=Ken
empNames[1]=Fred
empNames[2]=Li