public class Scope
1: // Fig. 6.11: Scope.java
2: // Scope class demonstrates field and local variable scopes.
3:
4: public class Scope
5: {
6: // field that is accessible to all methods of this class
7: private int x = 1;
8:
9: // method begin creates and initializes local variable x
10: // and calls methods useLocalVariable and useField
11: public void begin()
12: {
13: int x = 5; // method's local variable x shadows field x
14:
15: System.out.printf( "local x in method begin is %d\n", x );
16:
17: useLocalVariable(); // useLocalVariable has local x
18: useField(); // useField uses class Scope's field x
19: useLocalVariable(); // useLocalVariable reinitializes local x
20: useField(); // class Scope's field x retains its value
21:
22: System.out.printf( "\nlocal x in method begin is %d\n", x );
23: } // end method begin
24:
25: // create and initialize local variable x during each call
26: public void useLocalVariable()
27: {
28: int x = 25; // initialized each time useLocalVariable is called
29:
30: System.out.printf(
31: "\nlocal x on entering method useLocalVariable is %d\n", x );
32: ++x; // modifies this method's local variable x
33: System.out.printf(
34: "local x before exiting method useLocalVariable is %d\n", x );
35: } // end method useLocalVariable
36:
37: // modify class Scope's field x during each call
38: public void useField()
39: {
40: System.out.printf(
41: "\nfield x on entering method useField is %d\n", x );
42: x *= 10; // modifies class Scope's field x
43: System.out.printf(
44: "field x before exiting method useField is %d\n", x );
45: } // end method useField
46: } // end class Scope
47:
48: /**************************************************************************
49: * (C) Copyright 1992-2005 by Deitel & Associates, Inc. and *
50: * Pearson Education, Inc. All Rights Reserved. *
51: * *
52: * DISCLAIMER: The authors and publisher of this book have used their *
53: * best efforts in preparing the book. These efforts include the *
54: * development, research, and testing of the theories and programs *
55: * to determine their effectiveness. The authors and publisher make *
56: * no warranty of any kind, expressed or implied, with regard to these *
57: * programs or to the documentation contained in these books. The authors *
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59: * consequential damages in connection with, or arising out of, the *
60: * furnishing, performance, or use of these programs. *
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