C# 3.0 Design Patterns

Errata for C# 3.0 Design Patterns

Submit your own errata for this product.


The errata list is a list of errors and their corrections that were found after the product was released. If the error was corrected in a later version or reprint the date of the correction will be displayed in the column titled "Date Corrected".

The following errata were submitted by our customers and approved as valid errors by the author or editor.

Color Key: Serious Technical Mistake Minor Technical Mistake Language or formatting error Typo Question Note Update



Version Location Description Submitted By Date Submitted Date Corrected
Other Digital Version
xvi

Line -15 Inserted after the words web site, the phrase http://patterns.cs.up.ac.za. There is also an official O'Reilly website at

Anonymous    Jul 01, 2008
Other Digital Version
xxi

Inserted after the last line: My sincere thanks to all the readers who have send in comments and suggested corrections. I particularly wish to thank Philip Fitzimmons, Dominik Gruntz and Brian Holland for their careful reading of the text. Jim Whitehead, Nigel Horspool and Alastair van Leeuwen continually make me defend my corner in the nicest possible way, leading to a better book all round. Judith Bishop July 2008

Anonymous    Jul 01, 2008
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Page xvi

Line -15 Inserted after the words web site, the phrase http://patterns.cs.up.ac.za. There is also an official O’Reilly website at

Anonymous    Aug 01, 2008
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Page xxi

Inserted after the last line: My sincere thanks to all the readers who have send in comments and suggested corrections. I particularly wish to thank Philip Fitzimmons, Dominik Gruntz and Brian Holland for their careful reading of the text. Jim Whitehead, Nigel Horspool and Alastair van Leeuwen continually make me defend my corner in the nicest possible way, leading to a better book all round. Judith Bishop July 2008

Anonymous    Aug 01, 2008
Other Digital Version
11

Line 12 Replaced "inherits" with "implements"

Anonymous    Jul 01, 2008
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Page 11

Line 12 Replaced inherits from by implements

Anonymous    Aug 01, 2008
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12

Line 13 Removed this line entirely (IComponent Any Photo). It is a duplicate of the first line in the table.

Anonymous    Jul 01, 2008
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Page 12

Line 13 Removed this line entirely (IComponent Any Photo). It is a duplicate of the first line in the table.

Anonymous    Aug 01, 2008
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17

Line -11 Replaced Tag with TaggedPhoto keeping the courier font

Anonymous    Jul 01, 2008
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17

Line -8 Replaced Tag with TaggedPhoto keeping the courier font

Anonymous    Jul 01, 2008
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17

Line -7 Replaced Tag with TaggedPhoto keeping the courier font

Anonymous    Jul 01, 2008
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Page 17

Line –11 Replaced Tag with TaggedPhoto keeping the courier font

Anonymous    Aug 01, 2008
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Page 17

Line –8 Replaced Tag with TaggedPhoto keeping the courier font

Anonymous    Aug 01, 2008
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Page 17

Line –7 Replaced Tag with TaggedPhoto keeping the courier font

Anonymous    Aug 01, 2008
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18

Line 1 Replaced Tags with TaggedPhoto class keeping the courier font for the first word only

Anonymous    Jul 01, 2008
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18

Line 1 Replaced Tag with TaggedPhoto keeping the courier font

Anonymous    Jul 01, 2008
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Page 18

Line 1 Replaced Tags with TaggedPhoto class keeping the courier font for the first word only

Anonymous    Aug 01, 2008
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Page 18

Line 1 Replaced Tag with TaggedPhoto keeping the courier font

Anonymous    Aug 01, 2008
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19

Line 8 Inserted the word static in courier font before the word List and moved everything so that static lines up under static just above it in line 7

Anonymous    Jul 01, 2008
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Page 19

Line 8 Inserted the word static in courier font before the word List and moved everything so that static lines up under static just above it in line 7

Anonymous    Aug 01, 2008
Other Digital Version
21

Lines -15 to -13 Replaced Exercise 1 entirely by the following: 1 Referring to Example 2-1, write a new DecoratorC and experiment with new calls to the Display method from the Main method in the Client to produce different effects.

Anonymous    Jul 01, 2008
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Page 21

Lines –15 to –13 Replaced Exercise 1 entirely by the following: 1 Referring to Example 2-1, write a new DecoratorC and experiment with new calls to the Display method from the Main method in the Client to produce different effects.

Anonymous    Aug 01, 2008
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24

Line -6 Added closing parenthesis after proxy

Anonymous    Jul 01, 2008
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Page 24

Line –6 Added closing parenthesis after proxy

Anonymous    Aug 01, 2008
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27

Line -2 Removed the word ProtectionProxy and move the line back so that subject lines up above Console on the last line.

Anonymous    Jul 01, 2008
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Page 27

Line –2 Removed the word ProtectionProxy and move the line back so that subject lines up above Console on the last line.

Anonymous    Aug 01, 2008
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29

Line 16 Replaced RealSpaceBook by SpaceBook in the same font

Anonymous    Jul 01, 2008
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29

Line 17 Replaced RealSpaceBook by SpaceBook in the same font

Anonymous    Jul 01, 2008
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29

Line 21 Replaced IsUnique by IsUsed in the same font

Anonymous    Jul 01, 2008
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Page 29

Line 16 Replaced RealSpaceBook by SpaceBook in the same font

Anonymous    Aug 01, 2008
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Page 29

Line 17 Replaced RealSpaceBook by SpaceBook in the same font

Anonymous    Aug 01, 2008
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Page 29

Line 21 Replaced IsUnique by IsUsed in the same font

Anonymous    Aug 01, 2008
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30

Line 7 Replaced Unique by IsUsed in the same font

Anonymous    Jul 01, 2008
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30

Line -2 Lined Today I worked 18 hours up under Hello World

Anonymous    Jul 01, 2008
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Page 30

Line 7 Replaced Unique by IsUsed in the same font

Anonymous    Aug 01, 2008
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Page 30

Line 17 Deleted the first the

Anonymous    Aug 01, 2008
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Page 30

Line –2 Lined Today I worked 18 hours up under Hello World

Anonymous    Aug 01, 2008
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31

Line 19 Replaced SpaceBook with MySpaceBook in the same font

Anonymous    Jul 01, 2008
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31

Line 20 Replaced SpaceBook with MySpaceBook in the same font

Anonymous    Jul 01, 2008
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Page 31

Line 19 Replaced SpaceBook by MySpaceBook in the same font

Anonymous    Aug 01, 2008
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Page 31

Line 20 Replaced SpaceBook by MySpaceBook in the same font

Anonymous    Aug 01, 2008
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32

Line 9 Replaced IsUnique by IsUsed in the same font

Anonymous    Jul 01, 2008
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32

Line -2 Replaced Unique with IsUsed in the same font

Anonymous    Jul 01, 2008
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Page 32

Line 9 Replaced IsUnique by IsUsed in the same font

Anonymous    Aug 01, 2008
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Page 32

Line –2 Replaced Unique by IsUsed in the same font

Anonymous    Aug 01, 2008
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34

Line 20 Lined Today I worked 18 hours up under Hello World

Anonymous    Jul 01, 2008
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Page 34

Line 20 Lined Today I worked 18 hours up under Hello World

Anonymous    Aug 01, 2008
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37

Captions The Captions on these two figures are interchanged. Under the larger screen shot that comes first we want: Figure 2-6 Bridge pattern illustration (a) --environment Path variable set to Version 3.5 Under the smaller screen shot we want Figure 2-7. Bridge pattern illustration (b) -- five versions of the .NET Framework installed

Anonymous    Jul 01, 2008
Printed
Page 37

Captions The Captions on these two figures are interchanged. Under the larger screen shot that comes first we want: Figure 2-6 Bridge pattern illustration (a) – environment Path variable set to Version 3.5 Under the smaller screen shot we want Figure 2-7. Bridge pattern illustration (b) – five versions of the .NET Framework installed

Anonymous    Aug 01, 2008
Printed
Page 51

Fig 3-2 Delete the arrowed line between Component and Composite.
Create a line from IComponent down to Composite with an open arrow on the Composite end.

Anonymous   
Other Digital Version
54-55

Lines 6 and 7 Replaced all the code on these two pages by this code: 1 using System; 2 using System.Collections.Generic; 3 using System.Text; // for StringBuilder 4 5 // Composite Pattern Theory Judith Bishop Dec 2006, Aug 2007 6 // Arranges structures hierarchies so that single components and 7 // composite groups of components can be treated in the same way. 8 // Revised July 2008 9 10 namespace CompositePattern { 11 12 // The Interface 13 public interface IComponent <T> { 14 void Add(IComponent <T> c); 15 IComponent <T> Remove(T s); 16 string Display(int depth); 17 IComponent <T> Find(T s); 18 T Name {get; set;} 19 } 20 21 // The Component 22 public class Component <T> : IComponent <T> { 23 public T Name {get; set;} 24 25 public Component (T name) { 26 Name = name; 27 } 28 29 public void Add(IComponent <T> c) { 30 Console.WriteLine("Cannot add to an item"); 31 } 32 33 public IComponent <T> Remove(T s) { 34 Console.WriteLine("Cannot remove directly"); 35 return this; 36 } 37 38 public string Display(int depth) { 39 return new String('-', depth) + Name+" "; 40 } 41 42 public IComponent <T> Find (T s) { 43 if (s.Equals(Name)) 44 return this; 45 else 46 return null; 47 } 48 } 49 50 // The Composite 51 public class Composite <T> : IComponent <T> { 52 List <IComponent <T>> list; 53 54 public T Name {get; set;} 55 56 public Composite (T name) { 57 Name = name; 58 list = new List <IComponent <T>> (); 59 } 60 61 public void Add(IComponent <T> c) { 62 list.Add(c); 63 } 64 65 // Finds the item from a particular point in the structure 66 // and returns the composite from which it was removed 67 // If not found, return the point as given 68 public IComponent <T> Remove(T s) { 69 IComponent <T> p = this.Find(s); 70 if (this!=null) { 71 (this as Composite<T>).list.Remove(p); 72 } 73 return this; 74 } 75 76 // Recursively looks for an item 77 // Returns its reference or else null 78 public IComponent <T> Find (T s) { 79 if (Name.Equals(s)) return this; 80 IComponent <T> found=null; 81 foreach (IComponent <T> c in list) { 82 found = c.Find(s); 83 if (found!=null) 84 break; 85 } 86 return found; 87 } 88 89 // Displays items in a format indicating their level 90 // in the composite structure 91 public string Display(int depth) { 92 StringBuilder s = 93 new StringBuilder(new String('-', depth)); 94 s.Append("Set "+ Name + " length :" + list.Count + " "); 95 foreach (IComponent <T> component in list) 96 s.Append(component.Display(depth + 2)); 97 return s.ToString(); 98 } 99 } 100 }

Anonymous    Jul 01, 2008
Printed
Page 54-55

Lines 6 and 7 Replaced all the code on these two pages by this code: 1 using System; 2 using System.Collections.Generic; 3 using System.Text; // for StringBuilder 4 5 // Composite Pattern Theory Judith Bishop Dec 2006, Aug 2007 6 // Arranges structures hierarchies so that single components and 7 // composite groups of components can be treated in the same way. 8 // Revised July 2008 9 10 namespace CompositePattern { 11 12 // The Interface 13 public interface IComponent <T> { 14 void Add(IComponent <T> c); 15 IComponent <T> Remove(T s); 16 string Display(int depth); 17 IComponent <T> Find(T s); 18 T Name {get; set;} 19 } 20 21 // The Component 22 public class Component <T> : IComponent <T> { 23 public T Name {get; set;} 24 25 public Component (T name) { 26 Name = name; 27 } 28 29 public void Add(IComponent <T> c) { 30 Console.WriteLine("Cannot add to an item"); 31 } 32 33 public IComponent <T> Remove(T s) { 34 Console.WriteLine("Cannot remove directly"); 35 return this; 36 } 37 38 public string Display(int depth) { 39 return new String('-', depth) + Name+" "; 40 } 41 42 public IComponent <T> Find (T s) { 43 if (s.Equals(Name)) 44 return this; 45 else 46 return null; 47 } 48 } 49 50 // The Composite 51 public class Composite <T> : IComponent <T> { 52 List <IComponent <T>> list; 53 54 public T Name {get; set;} 55 56 public Composite (T name) { 57 Name = name; 58 list = new List <IComponent <T>> (); 59 } 60 61 public void Add(IComponent <T> c) { 62 list.Add(c); 63 } 64 65 // Finds the item from a particular point in the structure 66 // and returns the composite from which it was removed 67 // If not found, return the point as given 68 public IComponent <T> Remove(T s) { 69 IComponent <T> p = this.Find(s); 70 if (this!=null) { 71 (this as Composite<T>).list.Remove(p); 72 } 73 return this; 74 } 75 76 // Recursively looks for an item 77 // Returns its reference or else null 78 public IComponent <T> Find (T s) { 79 if (Name.Equals(s)) return this; 80 IComponent <T> found=null; 81 foreach (IComponent <T> c in list) { 82 found = c.Find(s); 83 if (found!=null) 84 break; 85 } 86 return found; 87 } 88 89 // Displays items in a format indicating their level 90 // in the composite structure 91 public string Display(int depth) { 92 StringBuilder s = 93 new StringBuilder(new String('-', depth)); 94 s.Append("Set "+ Name + " length :" + list.Count + " "); 95 foreach (IComponent <T> component in list) 96 s.Append(component.Display(depth + 2)); 97 return s.ToString(); 98 } 99 } 100 }

Anonymous    Aug 01, 2008
Other Digital Version
56

Line 2 Replaced "37-42" by "42-47"

Anonymous    Jul 01, 2008
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56

Line 5 Replaced 33-35 by 91-98

Anonymous    Jul 01, 2008
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Line 9 Replaced 46 by 51

Anonymous    Jul 01, 2008
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Line 14 Replaced 47 by 52

Anonymous    Jul 01, 2008
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56

Line 19 Replaced 65-74 by 68-74

Anonymous    Jul 01, 2008
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56

Line 21 Replaced 69 by 71

Anonymous    Jul 01, 2008
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56

Line 22 Replaced the word holder with this in the same font

Anonymous    Jul 01, 2008
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56

Line 23 Replaced The holder variable is of type ... with The this object could be of type ...

Anonymous    Jul 01, 2008
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56

Line 26 Replaced 82 and 94 with 81 and 95

Anonymous    Jul 01, 2008
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56

Line -6 Example Photo Library is now an "A" heading


Anonymous    Jul 01, 2008
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Page 56

Line 2 Replaced 37–42 by 42–47

Anonymous    Aug 01, 2008
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Line 5 Replaced 33-35 by 91–98

Anonymous    Aug 01, 2008
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Line 9 Replaced 46 by 51

Anonymous    Aug 01, 2008
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Line 14 Replaced 47 by 52

Anonymous    Aug 01, 2008
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Line 19 Replaced 65–74 by 68–74

Anonymous    Aug 01, 2008
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Line 21 Replaced 69 by 71

Anonymous    Aug 01, 2008
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Page 56

Line 22 Replaced the word holder by this in the same font

Anonymous    Aug 01, 2008
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Page 56

Line 23 Replaced The holder variable is of type … by The this object could be of type …

Anonymous    Aug 01, 2008
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Page 56

Line 26 Replaced 82 and 94 by 81 and 95

Anonymous    Aug 01, 2008
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Page 56

Line -6 Example Photo Library is now an "A" heading


Anonymous    Aug 01, 2008
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57

Line -9 Removed space in front of Set

Anonymous    Jul 01, 2008
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Page 57

Line –9 Removed space in front of Set

Anonymous    Aug 01, 2008
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58

Line 6 Removed space in front of Set

Anonymous    Jul 01, 2008
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Page 58

Line 6 Removed space in front of Set

Anonymous    Aug 01, 2008
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60

Line -17 Inserted a colon after <T> i.e. <T>:

Anonymous    Jul 01, 2008
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Page 60

Line –17 Inserted a colon after <T> i.e. <T>:

Anonymous    Aug 01, 2008
Other Digital Version
64

Line 15 Changed from "first of our four features" to "first of our five features"

Anonymous    Jul 01, 2008
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Page 64

Line 15 Changed from "first of our four features" to "first of our five features"

Anonymous    Aug 01, 2008
Other Digital Version
65

Line 19 Added t he instruction (See over) after "indexers".

Anonymous    Jul 01, 2008
Other Digital Version
65

Lines 26-29 Deleted these five lines, i.e. lines 6-9 of the code fragment

Anonymous    Jul 01, 2008
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65

Line -8 Replaced 13-14 by 9-10

Anonymous    Jul 01, 2008
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65

Line -6 Replaced 13 by 9 and 14 by 10

Anonymous    Jul 01, 2008
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65

Line -5 Replaced 10-16 with 6-12

Anonymous    Jul 01, 2008
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65

Line -4 Replaced 10 with 6

Anonymous    Jul 01, 2008
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65

Line -3 Replaced 12-14 by 8-10

Anonymous    Jul 01, 2008
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Page 65

Line 19 Added after indexers. The instruction (See over.)

Anonymous    Aug 01, 2008
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Page 65

Lines 26-29 Deleted these five lines, i.e. lines 6-9 of the code fragment

Anonymous    Aug 01, 2008
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Page 65

Line –8 Replaced 13–14 by 9–10

Anonymous    Aug 01, 2008
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Line –6 Replaced 13 by 9 and 14 by 10

Anonymous    Aug 01, 2008
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Line –5 Replaced 10–16 by 6–12

Anonymous    Aug 01, 2008
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Line –4 Replaced 10 by 6

Anonymous    Aug 01, 2008
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Page 65

Line –3 Replaced 12–14 by 8–10

Anonymous    Aug 01, 2008
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66

Line -8 Replaced collection with array

Anonymous    Jul 01, 2008
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Page 66

Line –8 Replaced collection by array

Anonymous    Aug 01, 2008
Other Digital Version
67

Lines 11-22 Replaced entirely by this code: // Flyweight public struct Flyweight : IFlyweight { // Intrinsic state Image pThumbnail; public void Load (string filename) { pThumbnail = new Bitmap("images/"+filename). GetThumbnailImage(100, 100, null, new IntPtr()); } public void Display(PaintEventArgs e, int row, int col) { // Calculating extrinsic state e.Graphics.DrawImage(pThumbnail,col*100+10, row*130+40, pThumbnail.Width,pThumbnail.Height); } }

Anonymous    Jul 01, 2008
Printed
Page 67

Lines 11–22 Replaced entirely by this code: // Flyweight public struct Flyweight : IFlyweight { // Intrinsic state Image pThumbnail; public void Load (string filename) { pThumbnail = new Bitmap("images/"+filename). GetThumbnailImage(100, 100, null, new IntPtr()); } public void Display(PaintEventArgs e, int row, int col) { // Calculating extrinsic state e.Graphics.DrawImage(pThumbnail,col*100+10, row*130+40, pThumbnail.Width,pThumbnail.Height); } }

Anonymous    Aug 01, 2008
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Page 67

Lines –14 to –16 Deleted these three lines and the blank line below.

Anonymous    Aug 01, 2008
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77

Line -5 Replaced DifferentRequest with SpecificRequest in the same font

Anonymous    Jul 01, 2008
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Page 77

Line –5 Replaced DifferentRequest by SpecificRequest in the same font

Anonymous    Aug 01, 2008
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80

Line 8 Replaced interfaces with from both classes

Anonymous    Jul 01, 2008
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Page 80

Line 8 Replaced interfaces by from both classes

Anonymous    Aug 01, 2008
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87

Line 17 Inserted after the word respectively: There is also another set of generic delegates introduced with the name Action that represent methods that do not return a value.

Anonymous    Jul 01, 2008
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Page 87

Line 17 Inserted after the word respectively: There is also another set of generic delegates introduced with the name Action that represent methods that do not return a value.

Anonymous    Aug 01, 2008
Other Digital Version
95

Lines -14 -12 -8 -5 -1 Replaced all occurrences of Façade in courier font by Facade in courier font (no cidilla). Removing the cidilla only applies to the courier Façade, not when the word is used in plain text.

Anonymous    Jul 01, 2008
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Page 95

Lines -14 -12 -8 -5 -1 Replaced all occurrences of Façade in courier font by Facade in courier font (no cidilla). Removing the cidilla only applies to the courier Façade, not when the word is used in plain text.

Anonymous    Aug 01, 2008
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97

Lines -12 -6 -2 Replaced all occurrences of Façade in courier font by Facade in courier font (no cidilla).

Anonymous    Jul 01, 2008
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Page 97

Lines -12 -6 -2 Replaced all occurrences of Façade in courier font by Facade in courier font (no cidilla).

Anonymous    Aug 01, 2008
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98

Lines 6 7 9 10 Replaced all occurrences of Façade in courier font by Facade in courier font (no cidilla).

Anonymous    Jul 01, 2008
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Page 98

Lines 6 7 9 10 Replaced all occurrences of Façade in courier font by Facade in courier font (no cidilla).

Anonymous    Aug 01, 2008
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Page 111

Fig 5-3 Inside the box called Creator, the last word should be IProduct not Product

Anonymous   
Other Digital Version
112

Line 14 Replaced Shoekeeper with Shopkeeper

Anonymous    Jul 01, 2008
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Page 112

Line 14 Replaced Shoekeeper by Shopkeeper

Anonymous    Aug 01, 2008
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116

Line 14 Removed the detail (3)

Anonymous    Jul 01, 2008
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Page 116

Line 14 Removed the detail (3)

Anonymous    Aug 01, 2008
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118

Line -6 Replaced Instance by UniqueInstance in the same font

Anonymous    Jul 01, 2008
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Page 118

Line -6 Replaced Instance by UniqueInstance in the same font

Anonymous    Aug 01, 2008
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121

Line -8 Replaced 25-27 by 26-28

Anonymous    Jul 01, 2008
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Line -8 Replaced 25-27 by 26-28

Anonymous    Aug 01, 2008
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134

Line 21 Replaced 49 by 59

Anonymous    Jul 01, 2008
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Line 21 Replaced 49 by 59

Anonymous    Aug 01, 2008
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Page 141

Fig 7-2 The box on the left should be called Context not Client

Anonymous   
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Page 165

Fig 8-2 The large box in the centre called IHandler:
Change its name to IHandler (not italic). The word Handler should be IHandler in plain (not italic) arial font There should be a line coming out of the top of this box, along, down and back into the box on its right side, with an open diamond at this end.

Anonymous   
Other Digital Version
209

Line 1 Replaced Mediator constructor with Mediator's sign on method with mediator in courier font.

Anonymous    Jul 01, 2008
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Page 209

Line 1 Replaced Mediator constructor by Mediator’s sign on method with mediator in courier font.

Anonymous    Aug 01, 2008
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Page 222

Fig 10-3 Remove the line between Client and Visitor1 boxes
Add a dotted line out the top of the Client box into the left side IVisitor box at the top. There should be an open arrow on the Visitor side of the line.

Anonymous   
Printed
Page 235

Fig 10-5 Remove the line between the Terminal and Nonterminal boxes. Replace the name of the Term box by ITerm Add a solid line out of the right side of ITerm coming down to the top of Nonterminal with an open diamond on this end.

Anonymous   
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245

Line -4 Replaced GetMemento by Restore

Anonymous    Jul 01, 2008
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Line -8 Replaced SetMemento by Save

Anonymous    Aug 01, 2008
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Line -4 Replaced GetMemento by Restore

Anonymous    Aug 01, 2008