UNIT 5

Question 1

Can you have multiple types of data in an array?

Answer 1

No, an array has to be the same datatype

Question 2

What is the index of the first value in the array?

Answer 2

0, this is because arrays in java use ZERO-BASE INDEXING

Question 3

What syntax would you use to declare an int array

Answer 3

int [] intArray;

Question 4

How would you instantiate an int array?

Answer 4

int [] intArray = new int[20];

Question 5

When an array is created what data will be in the array

Answer 5

Java will populate the data with default values

Question 6

How would you get the size of an array

Answer 6

nameOfArray.length

Question 7

How would you get the size of an ArrayList

Answer 7

arrayListReference.size();

Question 8

What is the structure for an enhanced for loop

Answer 8

for(dataValueType variableName: dataStructureName) {
}

ex:

for(String name:groupList) {

}

Question 9

In which cases can you not use an enhanced for loop

Answer 9

• if you need to change the contents of an element
• If you need to traverse the elements in a reverse order
• If you need to access only some, not all of the elements
• If you need to access more than one array or arrayList at a time inside the loop
• If you need to refer to the index number of a particular element