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lab02a
calling String methods

We saw in lecture that to use a variable, we

Declare the variable (For example: double height;)
initialize the variable (for example: height = 9.0;

Another example: here is how we declare a variable named bestSchool which stores the String value "Radford U.":

  String bestSchool;
  bestSchool = "Radford U.";

Once we do this, we can ask questions of that String — for example, we can ask for the character it has at index 2:

  bestSchool.charAt(2)

(How did we know that a method named “charAt” existed? We just had the teacher tell us, and s/he just looked it up in a reference book. It's relatively shallow knowledge.)

Practice task: In BlueJ's code pad:

Declare a variable named bestDorm whose type is String,

Initialize that variable to stand for "Muse Hall".

If we ask bestDorm what character it has at index 3, what answer will it give? Once you have figured out the answer you expecte, actually

Together, with the lab instructor: In the code pad, we'll ask Strings a different method. try calling a method named “replace”. whose answer is like the original string, except with one set of letters replaced with another.

Today's Task

P2.9 from the textbook (substituting letters in a String).

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©2009, Ian Barland, Radford University
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lab02a calling String methods

Today's Task

lab02a
calling String methods