# Frequently Asked Questions about Rhino

Q. How do I create a Java array from JavaScript?

A. You must use Java reflection. For instance, to create an array of java.lang.String of length five, do

> `var stringArray = java.lang.reflect.Array.newInstance(java.lang.String, 5);`

Then if you wish to assign the string "hi" to the first element, simply execute `stringArray[0] = "hi"`.

Creating arrays of primitive types is slightly different: you must use the TYPE field. For example, creating an array of seven ints can be done with the code

> `var intArray = java.lang.reflect.Array.newInstance(java.lang.Integer.TYPE, 7);`

Q. When I try to execute a script I get the exception `Required security context missing`. What's going on?

A. You've likely missed placing the `Security.properties` file in your class path at `org.mozilla.javascript.resources`.

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