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Posted to commits@sling.apache.org by bu...@apache.org on 2016/04/19 11:10:51 UTC
svn commit: r986067 - in /websites/staging/sling/trunk/content: ./
documentation/bundles/scripting/scripting-sightly.html
Author: buildbot
Date: Tue Apr 19 09:10:51 2016
New Revision: 986067
Log:
Staging update by buildbot for sling
Modified:
websites/staging/sling/trunk/content/ (props changed)
websites/staging/sling/trunk/content/documentation/bundles/scripting/scripting-sightly.html
Propchange: websites/staging/sling/trunk/content/
------------------------------------------------------------------------------
--- cms:source-revision (original)
+++ cms:source-revision Tue Apr 19 09:10:51 2016
@@ -1 +1 @@
-1739790
+1739874
Modified: websites/staging/sling/trunk/content/documentation/bundles/scripting/scripting-sightly.html
==============================================================================
--- websites/staging/sling/trunk/content/documentation/bundles/scripting/scripting-sightly.html (original)
+++ websites/staging/sling/trunk/content/documentation/bundles/scripting/scripting-sightly.html Tue Apr 19 09:10:51 2016
@@ -125,7 +125,10 @@ h2:hover > .headerlink, h3:hover > .head
<li><a href="#resource-backed-java-classes">Resource-backed Java classes</a></li>
</ul>
</li>
-<li><a href="#javascript-use-provider">JavaScript Use Provider</a></li>
+<li><a href="#javascript-use-provider">JavaScript Use Provider</a><ul>
+<li><a href="#caveats">Caveats</a></li>
+</ul>
+</li>
<li><a href="#script-use-provider">Script Use Provider</a></li>
<li><a href="#picking-the-best-use-provider-for-a-project">Picking the best Use Provider for a project</a></li>
</ul>
@@ -207,7 +210,7 @@ h2:hover > .headerlink, h3:hover > .head
<td>95</td>
<td><a href="https://github.com/apache/sling/blob/trunk/bundles/scripting/sightly/models-use-provider/src/main/java/org/apache/sling/scripting/sightly/models/impl/SlingModelsUseProvider.java"><code>SlingModelsUseProvider</code></a></td>
<td><code>org.apache.sling.scripting.sightly.models.provider</code></td>
-<td>support for loading Sling Models</td>
+<td>support for loading <a href="https://sling.apache.org/documentation/bundles/models.html">Sling Models</a></td>
<td></td>
</tr>
<tr>
@@ -326,7 +329,106 @@ Assuming the following content structure
<p>Similar to the Java Use Provider, loading the script using a relative path allows inheriting components to overlay just the Use script, without having to also overlay the calling Sightly script.</p>
-<p>The JavaScript files are evaluated by the <a href="https://developer.mozilla.org/en-US/docs/Mozilla/Projects/Rhino">Rhino</a> scripting engine, through the <code>org.apache.sling.scripting.javascript</code> implementation bundle. Since these scripts are evaluated server-side, by compiling JavaScript to Java, you need to pay attention when comparing objects using the strict equal operator (<code>===</code>) since comparisons between JavaScript and Java objects with the same apparent value will return <code>false</code> (this also applies to the strict not-equal operator - <code>!==</code>).</p>
+<h4 id="caveats">Caveats<a class="headerlink" href="#caveats" title="Permanent link">¶</a></h4>
+<p>The JavaScript files are evaluated by the <a href="https://developer.mozilla.org/en-US/docs/Mozilla/Projects/Rhino">Rhino</a> scripting engine, through the <code>org.apache.sling.scripting.javascript</code> implementation bundle.</p>
+<p>Since these scripts are evaluated server-side, by compiling JavaScript to Java, you need to pay attention when comparing primitive objects using the strict equal operator (<code>===</code>) since comparisons between JavaScript and Java objects with the same apparent value will return <code>false</code> (this also applies to the strict not-equal operator - <code>!==</code>).</p>
+<p>Assuming the following Sightly script:</p>
+<div class="codehilite"><pre> <span class="nt"><ol</span> <span class="err">data-sly-use.</span><span class="na">obj=</span><span class="s">"logic.js"</span> <span class="na">data-sly-list=</span><span class="s">"</span><span class="cp">${</span><span class="n">obj</span><span class="cp">}</span><span class="s">"</span><span class="nt">></span>
+ <span class="nt"><li></span>
+ Code <span class="nt"><code></span><span class="cp">${</span><span class="n">item</span><span class="o">.</span><span class="n">code</span><span class="cp">}</span><span class="nt"></code></span> evaluates to <span class="nt"><code></span><span class="cp">${</span><span class="n">item</span><span class="o">.</span><span class="n">result</span><span class="cp">}</span><span class="nt"></code></span>
+ <span class="nt"></li></span>
+ <span class="nt"></ol></span>
+</pre></div>
+
+
+<p>and the following JavaScript file:</p>
+<div class="codehilite"><pre> <span class="n">use</span><span class="p">(</span><span class="k">function</span><span class="p">()</span> <span class="p">{</span>
+
+ <span class="k">return</span> <span class="p">[</span>
+ <span class="p">{</span>
+ <span class="n">code</span><span class="p">:</span> <span class="s">'new java.lang.String("apples") === "apples"'</span><span class="p">,</span>
+ <span class="n">result</span><span class="p">:</span> <span class="n">new</span> <span class="n">java</span><span class="p">.</span><span class="n">lang</span><span class="p">.</span><span class="n">String</span><span class="p">(</span>"<span class="n">apples</span>"<span class="p">)</span> <span class="o">==</span><span class="p">=</span> "<span class="n">apples</span>"
+ <span class="p">},</span>
+ <span class="p">{</span>
+ <span class="n">code</span><span class="p">:</span> <span class="s">'new java.lang.String("apples") == "apples"'</span><span class="p">,</span>
+ <span class="n">result</span><span class="p">:</span> <span class="n">new</span> <span class="n">java</span><span class="p">.</span><span class="n">lang</span><span class="p">.</span><span class="n">String</span><span class="p">(</span>"<span class="n">apples</span>"<span class="p">)</span> <span class="o">==</span> "<span class="n">apples</span>"
+ <span class="p">},</span>
+ <span class="p">{</span>
+ <span class="n">code</span><span class="p">:</span> <span class="s">'new java.lang.String("apples") !== "apples"'</span><span class="p">,</span>
+ <span class="n">result</span><span class="p">:</span> <span class="n">new</span> <span class="n">java</span><span class="p">.</span><span class="n">lang</span><span class="p">.</span><span class="n">String</span><span class="p">(</span>"<span class="n">apples</span>"<span class="p">)</span> !<span class="o">==</span> "<span class="n">apples</span>"
+ <span class="p">},</span>
+ <span class="p">{</span>
+ <span class="n">code</span><span class="p">:</span> <span class="s">'new java.lang.String("apples") != "apples"'</span><span class="p">,</span>
+ <span class="n">result</span><span class="p">:</span> <span class="n">new</span> <span class="n">java</span><span class="p">.</span><span class="n">lang</span><span class="p">.</span><span class="n">String</span><span class="p">(</span>"<span class="n">apples</span>"<span class="p">)</span> !<span class="p">=</span> "<span class="n">apples</span>"
+ <span class="p">},</span>
+ <span class="p">{</span>
+ <span class="n">code</span><span class="p">:</span> <span class="s">'new java.lang.Integer(1) === 1'</span><span class="p">,</span>
+ <span class="n">result</span><span class="p">:</span> <span class="n">new</span> <span class="n">java</span><span class="p">.</span><span class="n">lang</span><span class="p">.</span><span class="n">Integer</span><span class="p">(</span>1<span class="p">)</span> <span class="o">==</span><span class="p">=</span> 1
+ <span class="p">},</span>
+ <span class="p">{</span>
+ <span class="n">code</span><span class="p">:</span> <span class="s">'new java.lang.Integer(1) == 1'</span><span class="p">,</span>
+ <span class="n">result</span><span class="p">:</span> <span class="n">new</span> <span class="n">java</span><span class="p">.</span><span class="n">lang</span><span class="p">.</span><span class="n">Integer</span><span class="p">(</span>1<span class="p">)</span> <span class="o">==</span> 1
+ <span class="p">},</span>
+ <span class="p">{</span>
+ <span class="n">code</span><span class="p">:</span> <span class="s">'new java.lang.Integer(1) !== 1'</span><span class="p">,</span>
+ <span class="n">result</span><span class="p">:</span> <span class="n">new</span> <span class="n">java</span><span class="p">.</span><span class="n">lang</span><span class="p">.</span><span class="n">Integer</span><span class="p">(</span>1<span class="p">)</span> !<span class="o">==</span> 1
+ <span class="p">},</span>
+ <span class="p">{</span>
+ <span class="n">code</span><span class="p">:</span> <span class="s">'new java.lang.Integer(1) != 1'</span><span class="p">,</span>
+ <span class="n">result</span><span class="p">:</span> <span class="n">new</span> <span class="n">java</span><span class="p">.</span><span class="n">lang</span><span class="p">.</span><span class="n">Integer</span><span class="p">(</span>1<span class="p">)</span> !<span class="p">=</span> 1
+ <span class="p">},</span>
+ <span class="p">{</span>
+ <span class="n">code</span><span class="p">:</span> <span class="s">'java.lang.Boolean.TRUE === true'</span><span class="p">,</span>
+ <span class="n">result</span><span class="p">:</span> <span class="n">java</span><span class="p">.</span><span class="n">lang</span><span class="p">.</span><span class="n">Boolean</span><span class="p">.</span><span class="n">TRUE</span> <span class="o">==</span><span class="p">=</span> <span class="n">true</span>
+ <span class="p">},</span>
+ <span class="p">{</span>
+ <span class="n">code</span><span class="p">:</span> <span class="s">'java.lang.Boolean.TRUE == true'</span><span class="p">,</span>
+ <span class="n">result</span><span class="p">:</span> <span class="n">java</span><span class="p">.</span><span class="n">lang</span><span class="p">.</span><span class="n">Boolean</span><span class="p">.</span><span class="n">TRUE</span> <span class="o">==</span> <span class="n">true</span>
+ <span class="p">},</span>
+ <span class="p">{</span>
+ <span class="n">code</span><span class="p">:</span> <span class="s">'java.lang.Boolean.TRUE !== true'</span><span class="p">,</span>
+ <span class="n">result</span><span class="p">:</span> <span class="n">java</span><span class="p">.</span><span class="n">lang</span><span class="p">.</span><span class="n">Boolean</span><span class="p">.</span><span class="n">TRUE</span> !<span class="o">==</span> <span class="n">true</span>
+ <span class="p">},</span>
+ <span class="p">{</span>
+ <span class="n">code</span><span class="p">:</span> <span class="s">'java.lang.Boolean.TRUE != true'</span><span class="p">,</span>
+ <span class="n">result</span><span class="p">:</span> <span class="n">java</span><span class="p">.</span><span class="n">lang</span><span class="p">.</span><span class="n">Boolean</span><span class="p">.</span><span class="n">TRUE</span> !<span class="p">=</span> <span class="n">true</span>
+ <span class="p">}</span>
+ <span class="p">];</span>
+ <span class="p">});</span>
+</pre></div>
+
+
+<p>the output would be:</p>
+<div class="codehilite"><pre> 1<span class="p">.</span> <span class="n">Code</span> <span class="n">new</span> <span class="n">java</span><span class="p">.</span><span class="n">lang</span><span class="p">.</span><span class="n">String</span><span class="p">(</span>"<span class="n">apples</span>"<span class="p">)</span> <span class="o">==</span><span class="p">=</span> "<span class="n">apples</span>" <span class="n">evaluates</span> <span class="n">to</span> <span class="n">false</span>
+ 2<span class="p">.</span> <span class="n">Code</span> <span class="n">new</span> <span class="n">java</span><span class="p">.</span><span class="n">lang</span><span class="p">.</span><span class="n">String</span><span class="p">(</span>"<span class="n">apples</span>"<span class="p">)</span> <span class="o">==</span> "<span class="n">apples</span>" <span class="n">evaluates</span> <span class="n">to</span> <span class="n">true</span>
+ 3<span class="p">.</span> <span class="n">Code</span> <span class="n">new</span> <span class="n">java</span><span class="p">.</span><span class="n">lang</span><span class="p">.</span><span class="n">String</span><span class="p">(</span>"<span class="n">apples</span>"<span class="p">)</span> !<span class="o">==</span> "<span class="n">apples</span>" <span class="n">evaluates</span> <span class="n">to</span> <span class="n">true</span>
+ 4<span class="p">.</span> <span class="n">Code</span> <span class="n">new</span> <span class="n">java</span><span class="p">.</span><span class="n">lang</span><span class="p">.</span><span class="n">String</span><span class="p">(</span>"<span class="n">apples</span>"<span class="p">)</span> !<span class="p">=</span> "<span class="n">apples</span>" <span class="n">evaluates</span> <span class="n">to</span> <span class="n">false</span>
+ 5<span class="p">.</span> <span class="n">Code</span> <span class="n">new</span> <span class="n">java</span><span class="p">.</span><span class="n">lang</span><span class="p">.</span><span class="n">Integer</span><span class="p">(</span>1<span class="p">)</span> <span class="o">==</span><span class="p">=</span> 1 <span class="n">evaluates</span> <span class="n">to</span> <span class="n">false</span>
+ 6<span class="p">.</span> <span class="n">Code</span> <span class="n">new</span> <span class="n">java</span><span class="p">.</span><span class="n">lang</span><span class="p">.</span><span class="n">Integer</span><span class="p">(</span>1<span class="p">)</span> <span class="o">==</span> 1 <span class="n">evaluates</span> <span class="n">to</span> <span class="n">true</span>
+ 7<span class="p">.</span> <span class="n">Code</span> <span class="n">new</span> <span class="n">java</span><span class="p">.</span><span class="n">lang</span><span class="p">.</span><span class="n">Integer</span><span class="p">(</span>1<span class="p">)</span> !<span class="o">==</span> 1 <span class="n">evaluates</span> <span class="n">to</span> <span class="n">true</span>
+ 8<span class="p">.</span> <span class="n">Code</span> <span class="n">new</span> <span class="n">java</span><span class="p">.</span><span class="n">lang</span><span class="p">.</span><span class="n">Integer</span><span class="p">(</span>1<span class="p">)</span> !<span class="p">=</span> 1 <span class="n">evaluates</span> <span class="n">to</span> <span class="n">false</span>
+ 9<span class="p">.</span> <span class="n">Code</span> <span class="n">java</span><span class="p">.</span><span class="n">lang</span><span class="p">.</span><span class="n">Boolean</span><span class="p">.</span><span class="n">TRUE</span> <span class="o">==</span><span class="p">=</span> <span class="n">true</span> <span class="n">evaluates</span> <span class="n">to</span> <span class="n">false</span>
+ 10<span class="p">.</span> <span class="n">Code</span> <span class="n">java</span><span class="p">.</span><span class="n">lang</span><span class="p">.</span><span class="n">Boolean</span><span class="p">.</span><span class="n">TRUE</span> <span class="o">==</span> <span class="n">true</span> <span class="n">evaluates</span> <span class="n">to</span> <span class="n">true</span>
+ 11<span class="p">.</span> <span class="n">Code</span> <span class="n">java</span><span class="p">.</span><span class="n">lang</span><span class="p">.</span><span class="n">Boolean</span><span class="p">.</span><span class="n">TRUE</span> !<span class="o">==</span> <span class="n">true</span> <span class="n">evaluates</span> <span class="n">to</span> <span class="n">true</span>
+ 12<span class="p">.</span> <span class="n">Code</span> <span class="n">java</span><span class="p">.</span><span class="n">lang</span><span class="p">.</span><span class="n">Boolean</span><span class="p">.</span><span class="n">TRUE</span> !<span class="p">=</span> <span class="n">true</span> <span class="n">evaluates</span> <span class="n">to</span> <span class="n">false</span>
+</pre></div>
+
+
+<p>Evaluations of Java objects in JavaScript constructs where the operand is automatically type coerced will work, but Rhino might complain about the Java objects not correctly calling the Rhino helper function <code>Context.javaToJS()</code>. In order to avoid these warnings it's better to explicitly perform your comparisons like in the following example:</p>
+<div class="codehilite"><pre> <span class="k">if</span> <span class="p">(</span><span class="n">myObject</span><span class="p">)</span> <span class="p">{</span>
+ <span class="p">...</span>
+ <span class="p">}</span>
+ <span class="o">//</span> <span class="n">should</span> <span class="n">be</span> <span class="n">replaced</span> <span class="n">by</span>
+ <span class="k">if</span> <span class="p">(</span><span class="n">myObject</span> !<span class="p">=</span> <span class="n">null</span><span class="p">)</span> <span class="p">{</span>
+ <span class="p">...</span>
+ <span class="p">}</span>
+
+ <span class="n">myObject</span> ? <span class="s">'this'</span> <span class="p">:</span> <span class="s">'that'</span>
+ <span class="o">//</span><span class="n">should</span> <span class="n">be</span> <span class="n">replaced</span> <span class="n">by</span>
+ <span class="n">myObject</span> !<span class="p">=</span> <span class="n">null</span> ? <span class="s">'this'</span> <span class="p">:</span> <span class="s">'that'</span>
+</pre></div>
+
+
<h3 id="script-use-provider">Script Use Provider<a class="headerlink" href="#script-use-provider" title="Permanent link">¶</a></h3>
<p>The Script Use Provider allows loading objects evaluated by other script engines available on the platform. The same loading considerations as for the Java and JavaScript Use Providers apply.</p>
<h3 id="picking-the-best-use-provider-for-a-project">Picking the best Use Provider for a project<a class="headerlink" href="#picking-the-best-use-provider-for-a-project" title="Permanent link">¶</a></h3>
@@ -381,7 +483,7 @@ Assuming the following content structure
</td>
<td>
<ul>
- <li>harder to test and debug, relying mostly on end-to-end testing</li>
+ <li>harder to test and debug, relying mostly on end-to-end testing and console logging</li>
<li>slower to execute than both Sling Models and Java Use-API objects</li>
</ul>
</td>
@@ -401,7 +503,7 @@ Assuming the following content structure
</tr>
</table>
<div class="timestamp" style="margin-top: 30px; font-size: 80%; text-align: right;">
- Rev. 1739750 by radu on Mon, 18 Apr 2016 11:47:33 +0000
+ Rev. 1739874 by radu on Tue, 19 Apr 2016 09:10:29 +0000
</div>
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