Iterations
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Consider variable scope when designing loops
Be careful of the scope of variables defined in a loop. They are only in scope in the block in which they are defined. For example, a variable initialized in the initialization section of a for loop will only have scope within the block of that loop. In other words,
for (int i = 0; i < 5; i++) {
// i is
in scope here
}// i is out of scope here.
With do-while loops, a varaible decalred in the block is not available to the test. For example, the following loop may not work as expected.
do {
String
input = JOptionPane.showInputDialog("Type STOP to stop");
} while
(!input.equalsIgnoreCase("STOP"));The vairable input of type String is not in scope in the while test, because it is outside of the loop's block!