Exercises 13.03-06
"Jessica" is the 1st name in the array "names" System.out.println(Arrays.binarySearch(names, "Jessica"));
0
What is the first array index?
0
What is the last array index
1 less than the number of elements in the array
Which of these is correct: int grades []; or int[]grades?
Both are correct
Program design includes two related concepts; what are they?
Business of abstraction and utilizing program features
Does the size of the array need to be specified in the previous situation?
No
If you were to add one name to the list2 array, for a total of 7 names, would the 7th name be displayed?
No, because it only displays the first 6
Can the length field be changed?
No, it's a final variable
Is length a method?
No, it's an attribute
Write a java code for an array of 40 strings called "names" in one statement
String names [] = new String[40];
If you were to add one name to the "name" array, for a total of 5 names, would the 5th name be displayed? Why or why not?
Yes, because names.length is used in the for loop and the attribute value will change when you add additional elements
How does the "toString" method display elements of an arrays object?
converts array to a string that can be automatically printed
Write the java code that will allocate memory for 30 ages
int ages [30];
Write the java code to declare an int array called ages
int ages [];
"Diana" is NOT one of the names in the array "names" System.out.println(Arrays.binarySearch(names, "Diana"));
negative number
Method "toString", like all arrays methods, is _____, which means you need to use the arrays identifier.
static
What does length do when used with a java static array?
tells you the number of elements in the array
What method allows you to assign the same value to every element of an arrays object?
the fill method
"Brenda" is one of the names in the array "names" System.out.println(Arrays.binarySearch(names, "Brenda"));
the index of Brenda (an integer)
Why does the program not properly display the index values of the numbers beings searched for?
the list hasn't been sorted
Write the java code necessary to store the age of 18 in the very last element
ages [array.length - 1] = 18;
Write the java code necessary to store the age of 16 in the first element
ages[0] = 16;
In what order does the "arrays" method "sort" arrange the data?
ascending order
Each element of an array has an ______, which is placed between brackets.
Index
What error do you get if you use an index value that is too large?
ArrayIndexOutofBoundsException
Look at how we have calling the "Arrays" methods in this chapter. Are these "class" methods of "object" methods?
The arrays methods are class methods
What if instead of adding a name, you removed a couple names so now there are only 4 left in the array. What will happen when the program is executed?
The program crashes
What is displayed if you put an object, like an array, in a println statement?
You will get memory address
What is sorting important?
because you need to search data
Write java code for initialized array of double values called bob. The initialized values will be 1.1, 2.2, 3.3, 4.4, 5.5
double [] bob = {1.1,2.2,3.3,4.4,5.5};
Array processing includes 4 things. List them.
element display, assigning values, sorting and searching elements
Whether you have an array of integers, an array of real numbers, or an array of strings, what data type will the index always be?
integer
What is the biggest advantage of assigning data to an array using an "initialize list?"
it can assign different values to every array element location
