Apple WebObjects 3.5 Instrukcja Użytkownika Strona 115
- Strona / 218
- Spis treści
- BOOKMARKI
Oceniono. / 5. Na podstawie oceny klientów
Objects and State
115
The WOComponent class defines a method application, which provides
access to the component’s application object. So any component can access
application state this way:
//Java
public boolean isLuckyWinner() {
Number sessionCount = application().statisticsStore().get(
"Total Sessions Created");
if (sessionCount == 1000) {
return true;
return false;
}
// WebScript
- isLuckyWinner {
id sessionCount = [[[self application] statisticsStore]
objectForKey:@"Total Sessions Created"];
if (sessionCount == 100])
return YES;
return NO;
}
Sessions can access application state using the same method defined in
WOSession.
Application state persists for as long as the application is running. If your
site runs multiple instances of the same application, application state must
be accessible to all instances. In this case, application state might be best
stored in a file or database, where application instances could easily access
it. This approach is also useful as a safeguard against losing application state
(such as the number of visitors to the site) if an application instance crashes.
The Session Object and Session State
A more interesting type of state that web applications can store is the state
associated with a user’s session. This state might include the selections a
user makes from a catalog, the total cost of the selections so far, or the user’s
billing information.
You typically store session state as instance variables in your application’s
session object. It’s also possible to store session state within a special
dictionary provided by the session object, as we’ll see shortly.
Session state is directly accessible to any component within the application
(although those components can access only the state stored for their
current session). The WOComponent class defines a
session method that
provides this access. For example, the component can access a session’s
instance variable in this way:
- WEBOBJECTS 1
- DEVELOPER’S GUIDE 1
- Contents 3
- Table of Contents 5
- Part II Special Tasks 6
- Managing State 109 6
- Part III WebScript 7
- The WebScript Language 163 7
- Foundation Classes 187 7
- Index 211 7
- Introduction 9
- About This Book 11
- Other Useful Documentation 12
- WEBOBJECTS ESSENTIALS 15
- Chapter 1 17
- <DocumentRoot> 19
- Components 20
- Template 21
- Code or Script File 21
- Bindings 22
- Application Code 23
- Session Code 23
- A Note on WebObjects Classes 23
- Application Directory 24
- WebObjects Adaptors 26
- WODefaultApp 27
- Dynamic Elements 29
- Server-Side Dynamic Elements 31
- Chapter 2 Dynamic Elements 32
- .wod file: 33
- Declarations File Syntax 36
- Client-Side Java Components 37
- Common Methods 41
- Action Methods 43
- Chapter 3 Common Methods 44
- Application Initialization 47
- Session Initialization 48
- Component Initialization 49
- Request-Handling Methods 50
- Invoking an Action 52
- Generating a Response 53
- Chapter 4 55
- Debugging WebScript 57
- Debugging Java 57
- Debugging Techniques 58
- Using Trace Methods 59
- Programming Pitfalls to Avoid 60
- Java Programming Pitfalls 61
- Chapter 5 63
- Server and Application Level 65
- Session Level 66
- Request Level 68
- Page Level 69
- Database Integration Level 71
- Accessing the Session 74
- Assigning Input Values 78
- Generating the Response 80
- How HTML Pages Are Generated 82
- START:Calendar { 85
- SPECIAL TASKS 89
- Creating Reusable Components 91
- Simplifying Interfaces 96
- Intercomponent Communication 98
- Parent's Template File 99
- <DocRoot> 105
- Designing for Reusability 106
- Complete Declaration 107
- Partial Declaration 108
- Managing State 109
- Chapter 7 Managing State 112
- Objects and State 113
- State Storage Strategies 120
- Comparison of Storage Options 121
- State in the Server 123
- State in the Page 124
- State in Cookies 126
- Custom State-Storage Options 128
- Controlling Session State 133
- Setting Session Time-Out 134
- Controlling Component State 135
- Adjusting the Page Cache Size 136
- Using awake and sleep 137
- Client-Side Page Caching 139
- Chapter 8 141
- Choosing a Strategy 143
- Objective-C Java 146
- Chapter 9 149
- Maintaining a Log File 151
- Accessing Statistics 152
- Recording Extra Information 153
- Error Handling 154
- Performance Tips 156
- Compile the Application 157
- Control Memory Leaks 157
- Limit State Storage 158
- Limit Database Fetches 158
- Limit Page Sizes 158
- Installing Applications 159
- WEBSCRIPT 161
- The WebScript Language 163
- Objects in WebScript 165
- WebScript Language Elements 166
- Variables and Scope 167
- Assigning Values to Variables 168
- Invoking Methods 171
- Accessor Methods 171
- Sending a Message to a Class 172
- Creating Instances of Classes 173
- Data Types 174
- Statements and Operators 175
- Control-Flow Statements 176
- Arithmetic Operators 176
- Logical Operators 176
- Relational Operators 176
- Reserved Words 178
- “Modern” WebScript Syntax 179
- Advanced WebScript 181
- Categories 182
- Objective-C WebScript 183
- Chapter 11 187
- Foundation Objects 189
- Determining Equality 190
- Working With Strings 191
- Commonly Used String Methods 192
- Comparing Strings 194
- Converting String Contents 194
- Modifying Strings 195
- Storing Strings 195
- Working With Arrays 196
- Commonly Used Array Methods 196
- Creating Arrays 197
- Querying Arrays 197
- Sorting Arrays 198
- Adding and Removing Objects 198
- Working With Dictionaries 200
- Creating Dictionaries 202
- Querying Dictionaries 203
- Storing Dictionaries 205
- Working With Dates and Times 206
- Commonly Used Date Methods 207
- Representing Dates as Strings 208
- Retrieving Date Elements 208
- – minuteOfHour 209
- – secondOfMinute 209
Powiązane produkty i podręczniki dla Oprogramowanie Apple WebObjects 3.5
(12 strony)
(531 strony)
(376 strony)
(23 strony)© 2020, manymanuals.pl. Wszelkie prawa zastrzeżone. | 0.179 s |
Manymanuals.com
Manymanuals.de
Manymanuals.fr
Manymanuals.it
Manymanuals.pl
Manymanuals.cz
Manymanuals.es
Manymanuals-pt.com
Komentarze do niniejszej Instrukcji