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                <CODE>new</CODE>. The public no-argument constructor for the 
                <CODE>MIDlet</CODE> is called and returns without throwing an exception.
                The application typically does little or no initialization in this
                step. If an exception occurs, the application immediately enters
                the Destroyed state and is discarded.</P>
            </LI>
          </UL>

          <UL>
            <LI>
              <P>From the Active state after the
              <CODE>MIDlet.pauseApp()</CODE> method is called from the
              AMS and returns successfully.</P>
            </LI>

            <LI>
              <P>From the Active state when the 
                <CODE>MIDlet.notifyPaused()</CODE> method returns successfully to the
                <CODE>MIDlet</CODE>.</P>
            </LI>

            <LI>
              <P>From the Active state if <CODE>startApp</CODE> throws an 
                <CODE>MIDletStateChangeException</CODE>.</P>
            </LI>
          </UL>
        </TD>
      </TR>

      <TR>
        <TD width="20%">
          <P>Active</P>
        </TD>
        <TD width="80%">
          <P>The <CODE>MIDlet</CODE> is functioning normally. This state is
            entered:</P>

          <UL>
            <LI>
              <P>Just prior to the AMS calling the
              <CODE>MIDlet.startApp()</CODE> method.</P>
            </LI>
          </UL>
        </TD>
      </TR>

      <TR>
        <TD width="20%">
          <P>Destroyed</P>
        </TD>
        <TD width="80%">
          <P>The <CODE>MIDlet</CODE> has released all of its resources and
            terminated. This state is entered:</P>

          <UL>
            <LI>
              <P>When the AMS called the
              <CODE>MIDlet.destroyApp()</CODE> method and returns
              successfully, except in the case when the
              <CODE>unconditional</CODE> argument is false and a
              <CODE>MIDletStateChangeException</CODE> is thrown. The
              <CODE>destroyApp()</CODE> method shall release all
              resources held and perform any necessary cleanup so it
              may be garbage collected.</P>
            </LI>

            <LI>
              <P>When the <CODE>MIDlet.notifyDestroyed()</CODE> method returns
                successfully to the application. The <CODE>MIDlet</CODE> must have
                performed the equivalent of the <CODE>MIDlet.destroyApp()</CODE>
                method before calling <CODE>MIDlet.notifyDestroyed()</CODE>.</P>
            </LI>
          </UL>

          <P><B>Note:</B> This state is only entered once.</P>
        </TD>
      </TR>
    </TABLE>

    <P><BR>
      <BR>
    </P>

    <P>The states and transitions for a <CODE>MIDlet</CODE> are:</P>

    <P><IMG src="doc-files/App-States.gif" name="Graphic1" align="LEFT"
             width=377 height=309 border="0"><BR clear="LEFT">
      <BR>
      <BR>
    </P>

    <H2>MIDlet Lifecycle Model</H2>

    <P style="margin-bottom: 0in">A typical sequence of 
      <CODE>MIDlet</CODE> execution is:</P>
    
    <TABLE width="100%" border="2" cellpadding="2" cellspacing="3">
       <TR>
        <TH width="66%">
          Application Management Software
        </TH>
        <TH width="34%">
          <CODE>MIDlet</CODE>
        </TH>
      </TR>

      <TR>
        <TD width="66%">
          <P>The application management software creates a new instance of a
            <CODE>MIDlet</CODE>.</P>
        </TD>
        <TD width="34%">
          <P>The default (no argument) constructor for the 
            <CODE>MIDlet</CODE> is called; it is in the Paused state.</P>
        </TD>
      </TR>

      <TR>
        <TD width="66%">
          <P>The application management software has decided that it is an
            appropriate time for the <CODE>MIDlet</CODE> to run, so it calls
            the <CODE>MIDlet.startApp</CODE> method for it to enter the Active
            state.</P>
        </TD>
        <TD width="34%">
          <P>The <CODE>MIDlet</CODE> acquires any resources it needs and
            begins to perform its service.</P>
        </TD>
      </TR>

      <TR>
        <TD width="66%">
          <P>The application management software wants the MIDlet to
	    significantly reduce the amount of resources it is
	    consuming, so that they may temporarily be used by other
	    functions on the device such as a phone call or running
	    another MIDlet. The AMS will signal this request to the
	    MIDlet by calling the <CODE>MIDlet.pauseApp</CODE>
	    method. The MIDlet should then reduce its resource
	    consumption as much as possible.</P>
        </TD>
        <TD width="34%">
          <P>The <CODE>MIDlet</CODE> stops performing its service and might
            choose to release some resources it currently holds.</P>
        </TD>
      </TR>

      <TR>
        <TD width="66%">
          <P>The application management software has determined that the
            <CODE>MIDlet</CODE> is no longer needed, or perhaps needs to make
            room for a higher priority application in memory, so it signals the
            <CODE>MIDlet</CODE> that it is a candidate to be destroyed by
            calling the <CODE>MIDlet.destroyApp</CODE> method.</P>
        </TD>
        <TD width="34%">
          <P>If it has been designed to do so, the <CODE>MIDlet</CODE> saves
            state or user preferences and performs clean up.</P>
        </TD>
      </TR>
    </TABLE>

    <H2>MIDlet Interface</H2>

    <UL>
      <LI>
        <P><CODE>pauseApp</CODE> - the <CODE>MIDlet</CODE> SHOULD release
          any temporary resources and become passive</P>
      </LI>

      <LI>
        <P><CODE>startApp</CODE> - the <CODE>MIDlet</CODE>
          SHOULD acquire any resources it needs and resume</P>
      </LI>

      <LI>
        <P><CODE>destroyApp</CODE> - the <CODE>MIDlet</CODE> SHOULD save
          any state and release all resources</P>
      </LI>

      <LI>
        <P><CODE>notifyDestroyed</CODE> - the <CODE>MIDlet</CODE> notifies
          the application management software that it has cleaned up and is
          done</P>
      </LI>

      <LI>
        <P><CODE>notifyPaused</CODE> - the <CODE>MIDlet</CODE> notifies the
          application management software that it has paused</P>
      </LI>

      <LI>
        <P><CODE>resumeRequest</CODE> - the <CODE>MIDlet</CODE> asks
          application management software to be started again</P>
      </LI>

      <LI>
        <P><CODE>getAppProperty</CODE> - gets a named property from the
          <CODE>MIDlet</CODE></P>
      </LI>
    </UL>

    <H2>Application Implementation Notes</H2>

    <P>The application SHOULD take measures to avoid race conditions in
      the execution of the <CODE>MIDlet</CODE> methods. Each method may
      need to synchronize itself with the other methods avoid concurrency
      problems during state changes.</P>

    <H2>Example MIDlet Application</H2>

    <P>The example uses the MIDlet lifecycle to do a simple measurement
      of the speed of the Java Virtual Machine.</P>

<PRE><CODE>
import javax.microedition.midlet.*;      
      
/**      
 * An example MIDlet runs a simple timing test      
 * When it is started by the application management software it will      
 * create a separate thread to do the test.      
 * When it finishes it will notify the application management software      
 * it is done.      
 * Refer to the startApp, pauseApp, and destroyApp      
 * methods so see how it handles each requested transition.      
 */      
public class MethodTimes extends MIDlet implements Runnable {      
    // The state for the timing thread.      
    Thread thread;      
      
    /**      
     * Start creates the thread to do the timing.      
     * It should return immediately to keep the dispatcher      
     * from hanging.      
     */      
    public void startApp() {      
        thread = new Thread(this);      
        thread.start();      
    }      
      
    /**      
     * Pause signals the thread to stop by clearing the thread field.      
     * If stopped before done with the iterations it will      
     * be restarted from scratch later.      
     */      
    public void pauseApp() {      
        thread = null;      
    }      
      
    /**      
     * Destroy must cleanup everything.  The thread is signaled      
     * to stop and no result is produced.      
     */      
    public void destroyApp(boolean unconditional) {      
        thread = null;      
    }      
      
   /**      
     * Run the timing test, measure how long it takes to      
     * call a empty method 1000 times.      
     * Terminate early if the current thread is no longer      
     * the thread from the      
     */      
    public void run() {      
        Thread curr = Thread.currentThread();  // Remember which thread is current      
        long start = System.currentTimeMillis();      
        for (int i = 0; i &lt; 1000000 &amp;&amp; thread == curr; i++) {      
            empty();      
        }      
        long end = System.currentTimeMillis();      
      
        // Check if timing was aborted, if so just exit      
        // The rest of the application has already become quiescent.      
        if (thread != curr) {      
            return;      
        }      
        long millis = end - start;      
        // Reporting the elapsed time is outside the scope of this example.      
      
        // All done cleanup and quit      
        destroyApp(true);      
        notifyDestroyed();      
    }      
      
    /**      
     * An Empty method.      
     */      
    void empty() {      
    }      
}     </code></PRE>
<P>
<DL>
<DT><B>Since: </B><DD>MIDP 1.0</DD>
</DL>
<HR>

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