| <!DOCTYPE html |
| PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "../xhtml1-strict.dtd"> |
| <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en"> |
| <head> |
| <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /> |
| <link rel="stylesheet" type="text/css" href="../css/ot.css" /> |
| <link rel="stylesheet" type="text/css" href="../css/otjld.css" /> |
| <title>OT/J Language Definition v1.3</title> |
| </head> |
| <body class="otdt"> |
| <div id="content"> |
| <table class="nav"> |
| <tr> |
| <td class="back"><a id="top"></a><a href="s5.1.html" rel="prev"><< §5.1 Effect of team activation</a></td> |
| <td class="top"><a href="index.html" rel="contents">↑ Table of Contents ↑</a></td> |
| <td class="next"><a href="s5.3.html" rel="next">§5.3 Implicit team activation >></a></td> |
| </tr> |
| </table> |
| <div class="breadcrumb"><a class="nav" href="s5.html" rel="section">§5 Team Activation</a></div> |
| <div class="sect depth2" id="s5.2"> |
| <h2 class="sect">§5.2 Explicit team activation<a class="img" href="s5.2.html" |
| title="PermaLink to §5.2 Explicit team activation"><img style="vertical-align:text-top;margin-left:5px;" src="../images/permalink.png" |
| alt="" /></a></h2> |
| <div class="subsect depth3" id="s5.2.a"> |
| <h4 class="subsect">(a) <span class="title">Activation block</span><a class="img" href="s5.2.a.html" title="PermaLink to (a) Activation block"><img style="vertical-align:text-top;margin-left:5px;" src="../images/permalink.png" |
| alt="" /></a></h4> |
| <p>A team can be activated thread local by the block construct</p> |
| <div class="listing plain"><pre><b>within</b> (myTeam) { <i>stmts</i> }</pre></div> |
| <p>If <em>stmts</em> has only one statement this can be abbreviated to |
| </p> |
| <div class="listing plain"><pre><b>within</b> (myTeam) <i>stmt</i></pre></div> |
| <p>In these statements, <code>myTeam</code> must denote a team instance. |
| For the time of executing this block, this team instance is activated for the current thread, |
| which has entered the within block. |
| |
| </p> |
| <p>The <code>within</code> block statement guarantees that it leaves |
| the team in exactly the same activation state as it was in when |
| entering this block. This includes the cases of exceptions, meaning |
| that deactivation will also occur if the execution of the block |
| terminates abnormally. |
| |
| </p> |
| </div> |
| <div class="subsect depth3" id="s5.2.b"> |
| <h4 class="subsect">(b) <span class="title">Imperative activation</span><a class="img" href="s5.2.b.html" |
| title="PermaLink to (b) Imperative activation"><img style="vertical-align:text-top;margin-left:5px;" src="../images/permalink.png" |
| alt="" /></a></h4> |
| <p>Each team class implicitly provides methods from the predefined interface |
| <code>org.objectteams.ITeam</code> (super interface of all team classes) to control team |
| activation disregarding the block structure of the program. The methods <code>activate()</code> |
| and <code>deactivate()</code> are used to activate and deactivate a team instance for |
| the current thread.<br /> |
| If a team should be de-/activated for another thread this can be done by the methods |
| <code>activate(Thread aThread)</code> and <code>deactivate(Thread aThread)</code>. |
| In order to achieve global activation for all threads the predefined constant |
| <code>org.objectteams.Team.ALL_THREADS</code> is passed to these methods (e.g. |
| <code>activate(Team.ALL_THREADS)</code>).<br /> |
| Note, that this methods make no guarantees with respect to exceptions. |
| |
| </p> |
| </div> |
| <div class="subsect depth3" id="s5.2.c"> |
| <h4 class="subsect">(c) <span class="title">Multiple and mixed activations</span><a class="img" href="s5.2.c.html" |
| title="PermaLink to (c) Multiple and mixed activations"><img style="vertical-align:text-top;margin-left:5px;" src="../images/permalink.png" |
| alt="" /></a></h4> |
| <ul> |
| <li>If <code>activate()</code> is invoked on a team instance |
| that has been explicitly activated before, this statement has |
| no effect at all (note the difference in <a href="s5.3.a.html" title="§5.3.(a) Team level methods" |
| class="sect">§5.3.(a)</a> below). |
| <br /> |
| The same applies to deactivating an inactive team. |
| </li> |
| <li>If a team was already active when entering a <code>within</code> |
| block, it will remain active after leaving the block. |
| </li> |
| <li>If the team was active on entry of a <code>within</code> block |
| and if <code>deactivate()</code> is invoked on the same team |
| instance from within the <code>within</code> block, |
| leaving the block will re-activate the team. |
| </li> |
| </ul> |
| </div> |
| </div> |
| <table class="nav"> |
| <tr> |
| <td class="back"><a href="s5.1.html" rel="prev"><< §5.1 Effect of team activation</a></td> |
| <td class="top"><a href="index.html" rel="contents">↑ Table of Contents ↑</a></td> |
| <td class="next"><a href="s5.3.html" rel="next">§5.3 Implicit team activation >></a></td> |
| </tr> |
| </table> |
| <div class="breadcrumb"><a class="nav" href="s5.html" rel="section">§5 Team Activation</a></div> |
| </div> |
| <div id="footer"> |
| <hr /><a class="w3c img" href="http://jigsaw.w3.org/css-validator/check/referer" |
| shape="rect"><img src="../images/valid-css2-blue.png" alt="Valid CSS!" height="31" width="88" /></a><a class="w3c img" href="http://validator.w3.org/check?uri=referer" shape="rect"><img src="../images/valid-xhtml10-blue.png" alt="Valid XHTML 1.0 Strict" height="31" |
| width="88" /></a><address>© Stephan Herrmann, Christine Hundt, Marco Mosconi</address> |
| OT/J version 1.3 — last modified: 2011-05-15 |
| </div> |
| </body> |
| </html> |