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  Iterator i = players.iterator();
  while (i.hasNext()) {
    LocalPlayer player = (LocalPlayer) i.next();
    PlayerDetails details = 
      new PlayerDetails(player.getPlayerId(),
        player.getName(), player.getPosition(), 0.00);
      playerList.add(details);
  }

  return playerList;
}<a name="wp80177"> </a>
</pre></div>
<a name="wp80178"> </a><h3 class="pHeading2">
Finding the Players by Position
</h3>
<a name="wp80179"> </a><h4 class="pHeading3">
1. RosterClient
</h4>
<a name="wp80180"> </a><p class="pBody">
The client starts the procedure by invoking the <code class="cCode">getPlayersByPosition</code> method of the <code class="cCode">RosterEJB</code> session bean:
</p>
<div class="pPreformattedRelative"><pre class="pPreformattedRelative">
playerList = myRoster.getPlayersByPosition(&quot;defender&quot;);<a name="wp80181"> </a>
</pre></div>
<a name="wp80182"> </a><h4 class="pHeading3">
2. RosterEJB
</h4>
<a name="wp80183"> </a><p class="pBody">
The <code class="cCode">getPlayersByPosition</code> method retrieves the <code class="cCode">players</code> list by invoking the <code class="cCode">findByPosition</code> method of the <code class="cCode">PlayerEJB</code> entity bean:
</p>
<div class="pPreformattedRelative"><pre class="pPreformattedRelative">
public ArrayList getPlayersByPosition(String position) {

&nbsp;&nbsp;Collection players = null;

&nbsp;&nbsp;try {
&nbsp;&nbsp;&nbsp;&nbsp;players = playerHome.findByPosition(position);
&nbsp;&nbsp;} catch (Exception ex) {
&nbsp;&nbsp;&nbsp;&nbsp;throw new EJBException(ex.getMessage());
&nbsp;&nbsp;}

&nbsp;&nbsp;return copyPlayersToDetails(players);
}<a name="wp80185"> </a>
</pre></div>
<a name="wp80186"> </a><h4 class="pHeading3">
3. PlayerEJB
</h4>
<a name="wp80187"> </a><p class="pBody">
The <code class="cCode">LocalPlayerHome</code> interface defines the <code class="cCode">findByPosition</code> method:
</p>
<div class="pPreformattedRelative"><pre class="pPreformattedRelative">
public Collection findByPosition(String position)
&nbsp;&nbsp;throws FinderException;<a name="wp80188"> </a>
</pre></div>
<a name="wp80189"> </a><p class="pBody">
Because the <code class="cCode">PlayerEJB</code> entity bean uses container-managed persistence, the entity bean class (<code class="cCode">PlayerBean</code>) does not implement its finder methods. To specify the queries associated with the finder methods, EJB QL queries must be defined in the bean's deployment descriptor. For example, the <code class="cCode">findByPosition</code> method has this EJB QL query:
</p>
<div class="pPreformattedRelative"><pre class="pPreformattedRelative">
SELECT DISTINCT OBJECT(p) FROM Player p
WHERE p.position = ?1<a name="wp80191"> </a>
</pre></div>
<a name="wp80194"> </a><p class="pBody">
At runtime, when the container invokes the <code class="cCode">findByPosition</code> method, it will execute the corresponding SQL <code class="cCode">SELECT</code> statement.
</p>
<a name="wp80198"> </a><p class="pBody">
For details about EJB QL, please refer to Chapter&nbsp;<a  href="EJBQL.html#wp79663">24</a>. To learn how to view and edit an EJB QL query in <code class="cCode">deploytool</code>, see the section <a  href="CMP6.html#wp83132">Finder/Select Methods Dialog Box (PlayerEJB)</a>.
</p>
<a name="wp80202"> </a><h3 class="pHeading2">
Getting the Sports of a Player
</h3>
<a name="wp80203"> </a><h4 class="pHeading3">
1. RosterClient
</h4>
<a name="wp80204"> </a><p class="pBody">
The client invokes the <code class="cCode">getSportsOfPlayer</code> method of the <code class="cCode">RosterEJB</code> session bean:
</p>
<div class="pPreformattedRelative"><pre class="pPreformattedRelative">
sportList = myRoster.getSportsOfPlayer(&quot;P28&quot;);<a name="wp80205"> </a>
</pre></div>
<a name="wp80206"> </a><h4 class="pHeading3">
2. RosterEJB
</h4>
<a name="wp80207"> </a><p class="pBody">
The <code class="cCode">getSportsOfPlayer</code> method returns an <code class="cCode">ArrayList</code> of <code class="cCode">String</code> objects that represent the sports of the specified player. It constructs the <code class="cCode">ArrayList</code> from a <code class="cCode">Collection</code> returned by the <code class="cCode">getSports</code> business method of the <code class="cCode">PlayerEJB entity </code>bean. Here is the source code for the <code class="cCode">getSportsOfPlayer</code> method of the <code class="cCode">RosterEJB</code> session bean:
</p>
<div class="pPreformattedRelative"><pre class="pPreformattedRelative">
public ArrayList getSportsOfPlayer(String playerId) { 

&nbsp;&nbsp;ArrayList sportsList = new ArrayList();
&nbsp;&nbsp;Collection sports = null;

&nbsp;&nbsp;try {
&nbsp;&nbsp;&nbsp;&nbsp;LocalPlayer player =
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;playerHome.findByPrimaryKey(playerId);
&nbsp;&nbsp;&nbsp;&nbsp;sports = player.getSports();
&nbsp;&nbsp;} catch (Exception ex) {
&nbsp;&nbsp;&nbsp;&nbsp;throw new EJBException(ex.getMessage());
&nbsp;&nbsp;}
  
&nbsp;&nbsp;Iterator i = sports.iterator();
&nbsp;&nbsp;while (i.hasNext()) {
&nbsp;&nbsp;&nbsp;&nbsp;String sport = (String) i.next();
&nbsp;&nbsp;&nbsp;&nbsp;sportsList.add(sport);
&nbsp;&nbsp;}
&nbsp;&nbsp;return sportsList;
}<a name="wp80208"> </a>
</pre></div>
<a name="wp80209"> </a><h4 class="pHeading3">
3. PlayerEJB
</h4>
<a name="wp80210"> </a><p class="pBody">
The <code class="cCode">getSports</code> method is a wrapper for the <code class="cCode">ejbSelectSports</code> method. Since the parameter of the <code class="cCode">ejbSelectSports</code> method is of type <code class="cCode">LocalPlayer</code>, the <code class="cCode">getSports</code> method passes along a reference to the entity bean instance. The <code class="cCode">PlayerBean</code> class implements the <code class="cCode">getSports</code> method as follows:
</p>
<div class="pPreformattedRelative"><pre class="pPreformattedRelative">
public Collection getSports() throws FinderException {

&nbsp;&nbsp;LocalPlayer player = 
&nbsp;&nbsp;&nbsp;&nbsp;(team.LocalPlayer)context.getEJBLocalObject();
&nbsp;&nbsp;return ejbSelectSports(player);
}<a name="wp80211"> </a>
</pre></div>
<a name="wp80213"> </a><p class="pBody">
The <code class="cCode">PlayerBean</code> class defines the <code class="cCode">ejbSelectSports</code> method:
</p>
<div class="pPreformattedRelative"><pre class="pPreformattedRelative">
public abstract Collection ejbSelectSports(LocalPlayer player)
&nbsp;&nbsp;throws FinderException;<a name="wp80214"> </a>
</pre></div>
<a name="wp80215"> </a><p class="pBody">
The bean's deployment descriptor specifies the following EJB QL query for the <code class="cCode">ejbSelectSports</code> method:
</p>
<div class="pPreformattedRelative"><pre class="pPreformattedRelative">
SELECT DISTINCT t.league.sport
FROM Player p, IN (p.teams) AS t
WHERE p = ?1<a name="wp80216"> </a>
</pre></div>
<a name="wp80217"> </a><p class="pBody">
Because <code class="cCode">PlayerEJB</code> uses container-managed persistence, when the <code class="cCode">ejbSelectSports</code> method is invoked the EJB container will execute its corresponding SQL <code class="cCode">SELECT</code> statement.
</p>
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