Page History

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A related goal is to design the documentation so that it is easy to maintain, so that it remains tends to remain internally consistent with the framework itself.

• #Change Happens
• #About Headings
• #General Punctuation and Grammar

Change Happens

Anyone who has worked with databases knows the value of normalizing the schema. Ideally, we want to store each fact exactly once, and then use query system to retrieve that fact whereever it is needed. If we store a fact once, we only need to update it once, and we avoid inconsistencies in our data set.

Do it now. Do it once. Do it well.

Overall, there are three goals for the documentation system.

• Say it all
• Say it once
• Say it well

FirstTo the extent possible, we want to "normalize" our technical documentation. Like a database, all technical documentation is subject to change. When change happens, we want the documentation to be as easy to update complete as possible. One way to do that is to try and minimize redudency (without sacrificing ease of use).

Single sourcing with snippets

The "holy grail" of technical documentation is single sourcing. One way we try to single-source documentation is to pull content directly from the Javadocs and source code into the documentation.

Using a snippet macro, we are able to tag portions of the Javadocs and source code for reuse. The macro fetches those snippets from the repository and merges the conntent into the documentation.

Here are some examples of the snippet macro in action:

{snippet:id=description|javadoc=true|url=com.opensymphony.xwork.interceptor.LoggingInterceptor}

or

{snippet:id=example|javadoc=true|lang=xml|url=com.opensymphony.xwork.interceptor.LoggingInterceptor}

or

{snippet:id=sitegraph-usage|lang=none|url=webwork/src/java/com/opensymphony/webwork/sitegraph/sitegraph-usage.txt}

or

{snippet:id=ajax-validation-example|lang=xml|url=webwork/webapps/ajax/src/webapp/lesson1/example.jsp}

Legend:

All snippets are marked off by the pattern START SNIPPET: XXX and END SNIPPET: XXX where XXX is the name of the snippet that is assigned in the id attribute of the macro. The URL is typically a location that points to the project's source control contents.

About URLs

As you probably noticed in the examples, there are several formats for URL patterns. A fully-qualified URL is always allowed, though that is often not practical. We've customized the macro to be a bit more intelligent with the URL attribute.

• If the URL appears to be a class, we assume it lives in src/java, convert all the dots to slashes, and then append .java to it.
• If the URL doesn't start with "http", then it is assumed to start with _https://opensymphony.dev.java.net/source/browse/*checkout*/_, as you saw in the third example.

About snippet markers

When possible, all snippet markers should be in comment blocks. How they are commented depends on where the snippet is being embedded.

<!-- START SNIPPET: xxx -->
...
<!-- END SNIPPET: xxx -->

if (true != false) {
    // START SNIPPET: xxx
    System.out.println("This is some silly code!");
    // END SNIPPET: xxx
}

If the snippet is embedded in Javadocs, use HTML comments as they won't render in the Javadocs. For XML examples in Javadocs can be tricky. (See Timer Interceptor for an example.). Javadocs want to use the <pre> tag, but you don't want that tag in the snipped content.

One technique is to embed the snippet markers inside the <pre> tag.

This is job one! The documentation should be a repository of all the tips and tricks we use in our own applications, and it should also be a quick but comprehensive introduction to the framework, so newcomers can get started as easily as possible.

Second, the documentation should be easy to maintain. Ideally, we should cover the detail of each topic once, and draw as much detail from the source code and examples as possible (using the snippet macro).

Third, the documentation should be text-book quality; if not in the first draft, then in the next. Don't hesitate to hack in a new page. Better that we have the page than we don't. (See Job One!) But, as time allows, we should try to make each page the best that it can be. A lot of people access the documentation, and it's worth the effort to make the "documentation experience" productive and enjoyable.

Capitalization of common terms

• Java
• Javadoc
• HTML
• XML

General Punctuation and Grammar

Good online resources for punctuation, grammar, and text style include

• Punctuation Made Simple
• Associated Press Style Guide Essentials

In print, two excellent (and inexpensive!) resources are

• The Elements of Style
• Associated Press Stylebook

Quick Tips

• Use as few words as possible. Instead of "but there are some quirks about it" try "but there are quirks".
• If a list of items includes both a term and an explanation, consider using a table instead of bullets.
• Avoid using "This" by itself. Instead of "This lets us" try "This strategy lets us".
  • Ask yourself: "This what?"
• References to other wiki pages can be unqualified. Instead of "See Style Guide page", try "See Style Guide."

Don't be smurfy!

A lot of API members use the term "action". We have

• action extensions on pages,
• action attributes in forms,
• action elements in configuration files, and
• Action Java classes, some of which may implement the
• Action interface, and, of course, we're now calling the framework "Action" too!

Here are some terms that can be used to help clarify which action is which.

• Use "the framework" or "SAF2" to refer to Struts Action 2 as a whole, including any frameworks we use internally, like XWork and OGNL.
• Use "Action class" to refer to the Java class incorporated by the action element.
• Use "action mapping" to refer to the object created by the action element.

...

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About Headings

This section refers to: Notation Guide >> Headings.

...

...

General Punctuation and Grammar

Good online resources for punctuation, grammar, and text style include

• Punctuation Made Simple
• Associated Press Style Guide Essentials

In print, two excellent (and inexpensive!) resources are

...

More on Text Effects

This section refers to: Notation Guide >> Text Effects.

...

Always observe copyright issues. Do not annex images unless it an orginal or public domain work, or the author has donated the image to the foundation.

Example:

Icons

Use , , , and to bullet important one-liners. Use to highlight cross references.

Used carefully, icons such as , , or can make the content easier to read and understand.

...

$ javac HelloWorld.java

$ java HelloWorld
Hello, World!

Change Happens

Anyone who has worked with databases knows the value of normalizing the schema. Ideally, we want to store each fact exactly once, and then use query system to retrieve that fact whereever it is needed. If we store a fact once, we only need to update it once, and we avoid inconsistencies in our data set.

To the extent possible, we want to "normalize" our technical documentation. Like a database, all technical documentation is subject to change. When change happens, we want the documentation to be as easy to update as possible. One way to do that is to try and minimize redudency (without sacrificing ease of use).

Single sourcing with snippets

The "holy grail" of technical documentation is single sourcing. One way we try to single-source documentation is to pull content directly from the Javadocs and source code into the documentation.

Using a snippet macro, we are able to tag portions of the Javadocs and source code for reuse. The macro fetches those snippets from the repository and merges the conntent into the documentation.

Here are some examples of the snippet macro in action:

{snippet:id=description|javadoc=true|url=com.opensymphony.xwork.interceptor.LoggingInterceptor}

or

{snippet:id=example|javadoc=true|lang=xml|url=com.opensymphony.xwork.interceptor.LoggingInterceptor}

or

{snippet:id=sitegraph-usage|lang=none|url=webwork/src/java/com/opensymphony/webwork/sitegraph/sitegraph-usage.txt}

or

{snippet:id=ajax-validation-example|lang=xml|url=webwork/webapps/ajax/src/webapp/lesson1/example.jsp}

Legend:

All snippets are marked off by the pattern START SNIPPET: XXX and END SNIPPET: XXX where XXX is the name of the snippet that is assigned in the id attribute of the macro. The URL is typically a location that points to the project's source control contents.

About URLs

As you probably noticed in the examples, there are several formats for URL patterns. A fully-qualified URL is always allowed, though that is often not practical. We've customized the macro to be a bit more intelligent with the URL attribute.

• If the URL appears to be a class, we assume it lives in src/java, convert all the dots to slashes, and then append .java to it.
• If the URL doesn't start with "http", then it is assumed to start with _https://opensymphony.dev.java.net/source/browse/*checkout*/_, as you saw in the third example.

About snippet markers

When possible, all snippet markers should be in comment blocks. How they are commented depends on where the snippet is being embedded.

<!-- START SNIPPET: xxx -->
...
<!-- END SNIPPET: xxx -->

if (true != false) {
    // START SNIPPET: xxx
    System.out.println("This is some silly code!");
    // END SNIPPET: xxx
}

If the snippet is embedded in Javadocs, use HTML comments as they won't render in the Javadocs. For XML examples in Javadocs can be tricky. (See Timer Interceptor for an example.). Javadocs want to use the <pre> tag, but you don't want that tag in the snipped content.

One technique is to embed the snippet markers inside the <pre> tag.

* <pre>
 * <!-- START SNIPPET: example -->
 * &lt;!-- records only the action's execution time --&gt;
 * &lt;action name="someAction" class="com.examples.SomeAction"&gt;
 *     &lt;interceptor-ref name="completeStack"/&gt;
 *     &lt;interceptor-ref name="timer"/&gt;
 *     &lt;result name="success"&gt;good_result.ftl&lt;/result&gt;
 * &lt;/action&gt;
 * <!-- END SNIPPET: example -->