📄 getvolmem.htm

📁 这个压缩包里的都是超级经典的java例子
💻 HTM
字号:
<HTML>
<HEAD>
<META http-equiv="Content-Type" content="text/html; charset=UTF-8">
<TITLE>Getting Amount of Free Accelerated Image Memory (Java Developers Almanac Example)
</TITLE>
<META CONTENT="Patrick Chan" NAME="AUTHOR">
<META CONTENT="Code Examples from The Java Developers Almanac 1.4" NAME="DESCRIPTION">
<META CONTENT="Addison-Wesley/Patrick Chan" NAME="OWNER">
<META CONTENT="3/20/02" NAME="revision">
<META CONTENT="no-cache" HTTP-EQUIV="Pragma">
<LINK href="/almanac.css" media="screen" type="text/css" rel="stylesheet">
</HEAD>
<BODY>
<TABLE CELLSPACING="0" CELLPADDING="0" BORDER="0">
<TR>
<TD></TD>
</TR>
</TABLE>
<br>
<TABLE CELLSPACING="0" CELLPADDING="0" BORDER="0">
<TR>
<TD></TD>
</TR>
<TR>
<TD rowspan="3"><A HREF="/?l=ex"><IMG BORDER="0" ALIGN="BOTTOM" HSPACE="10" SRC="/egs/almanac14a.jpg"></A></TD><TD VALIGN="top">
<h1>The Java Developers Almanac 1.4</h1>
<br>
        Order this book from <a href="/cgi-bin/scripts/redirect.pl?l=ex&url=http://www.amazon.com/exec/obidos/ASIN/0201752808/xeo">Amazon</a>.
    </TD>
</TR>
<TR>
<TD align="right" valign="bottom">
<FORM method="get" action="/cgi-bin/search/find.pl">
<INPUT size="25" name="words" type="text"><INPUT value="Search" type="submit">
</FORM>
</TD>
</TR>
</TABLE>
<HR color="#6666cc">
<TABLE CELLSPACING="0" CELLPADDING="0" BORDER="0">
<TR>
<TD valign="top"><script type="text/javascript">
<!--
google_ad_client = "pub-6001183370374757";
google_ad_width = 120;
google_ad_height = 600;
google_ad_format = "120x600_as";
google_ad_channel = "4777242811";
google_ad_type = "text_image";
google_color_border = "FFFFFF";
google_color_bg = "FFFFFF";
google_color_link = "6666CC";
google_color_url = "6666CC";
google_color_text = "000000";
//--></script><script src="http://pagead2.googlesyndication.com/pagead/show_ads.js" type="text/javascript"></script></TD><TD>&nbsp;&nbsp;&nbsp;</TD><TD valign="top">
<DIV ALIGN="LEFT">
<A HREF="/">Home</A>
    &gt;
    <A HREF="../index.html">List of Packages</A>
    &gt;

    
    <A HREF="../java.awt.image/pkg.html">java.awt.image</A><font color="#666666" class="xsmall-font">
        &nbsp;[21 examples]
    </font>
        &gt;
        <B><A HREF="../java.awt.image/pkg.html#Volatile Images">Volatile Images</A></B><font color="#666666" class="xsmall-font">
            &nbsp;[2 examples]
            </font>
</DIV><P>
  <h3>e673. Getting Amount of Free Accelerated Image Memory</h3>

Images in accelerated memory are much faster to draw on the screen.
However, accelerated memory is typically limited and it is usually
necessary for an application to manage the images residing in this
space.  This example demonstrates how to determine the amount free
accelerated available.

<P> Note: There appears to be a problem with
<code>GraphicsDevice.getAvailableAcceleratedMemory()</code> on some systems.
The method returns 0 even if accelerated image memory is available.  A
workaround is to create a temporary volatile image on the graphics
device before calling the method.  Once the volatile image is created,
the method appears to return the correct value on all subsequent
calls.

<P> See also <a href="../java.awt/screen_FullWin.html" class="eglink"><b>e601</b> Enabling Full-Screen Mode</a> and
<a href="../java.awt.image/VolImage.html" class="eglink"><b>e674</b> Creating and Drawing an Accelerated Image</a>.


<pre>    GraphicsEnvironment ge = GraphicsEnvironment.getLocalGraphicsEnvironment();
    try {
        GraphicsDevice[] gs = ge.getScreenDevices();
    
        // Get current amount of available memory in bytes for each screen
        for (int i=0; i&lt;gs.length; i++) {
            // Workaround; see description
            VolatileImage im = gs[i].getDefaultConfiguration().createCompatibleVolatileImage(1, 1);
    
            // Retrieve available free accelerated image memory
            int bytes = gs[i].getAvailableAcceleratedMemory();
            if (bytes &lt; 0) {
                // Amount of memory is unlimited
            }
    
            // Release the temporary volatile image
            im.flush();
        }
    } catch (HeadlessException e) {
        // Is thrown if there are no screen devices
    }
</pre>
<P><table width="600" CELLSPACING="0" CELLPADDING="2" BORDER="0">
<tr>
<td bgcolor="#6666cc" align="center"><font color="#ffffff">
            &nbsp;<b>Related Examples</b></font></td>
</tr>
</table>


e674. <a class="eglink" href="VolImage.html?l=rel">
    Creating and Drawing an Accelerated Image
</a>
<br>


<table width="600" CELLSPACING="0" CELLPADDING="2" BORDER="0">
<tr>
<td align="left">
<br>
        See also: 
<a class="eglink" href="/egs/java.awt.image/pkg.html?l=rel#Buffered%20Images">
    Buffered Images
</a>&nbsp;&nbsp;

<a class="eglink" href="/egs/java.awt.image/pkg.html?l=rel#Effects">
    Effects
</a>&nbsp;&nbsp;

<a class="eglink" href="/egs/java.awt.image/pkg.html?l=rel#Images">
    Images
</a>&nbsp;&nbsp;

</td>
</tr>
</table>

<br>

<br>
<FONT class="xsmall-font">
&copy; 2002 Addison-Wesley.
</FONT></TD><TD>&nbsp;&nbsp;&nbsp;</TD><TD valign="top"><A href="http://compositesw.com/devzone?ref=javaalmanac"><IMG alt="Click Here" height="600" width="120" border="0" src="/csw_oad_120x600_final.gif"></A></TD>
</TR>
</TABLE>
</BODY>
<HEAD>
<META http-equiv="Content-Type" content="text/html; charset=UTF-8">
<META CONTENT="NO-CACHE" HTTP-EQUIV="PRAGMA">
</HEAD>
</HTML>
⌨️ 快捷键说明

复制代码 Ctrl + C
搜索代码 Ctrl + F
全屏模式 F11
切换主题 Ctrl + Shift + D
显示快捷键 ?
增大字号 Ctrl + =
减小字号 Ctrl + -