<DIV>The 1.4 compiler (javac) targets the 1.2 jvm by default. The following is from the 1.4.2 JDK:</DIV>
<DIV><A name=crosscomp-options> </DIV>
<H3>Cross-Compilation Options</H3></A>
<BLOCKQUOTE>
<P>By default, classes are compiled against the bootstrap and extension classes of the platform that <B>javac</B> shipped with. But <B>javac</B> also supports <I>cross-compiling</I>, where classes are compiled against a bootstrap and extension classes of a different Java platform implementation. It is important to use <B>-bootclasspath</B> and <B>-extdirs</B> when cross-compiling; see <A href="http://java.sun.com/j2se/1.4.2/docs/tooldocs/solaris/javac.html#crosscomp-example">Cross-Compilation Example</A> below.
<DL>
<P>
<DT><B>-target</B> <I>version</I>
<DD>Generate class files that will work on VMs with the specified version. The default is to generate class files to be compatible with the 1.2 VM in the Java 2 SDK, with one exception. When the <TT>-source 1.4</TT> option is used, the default target is 1.4. The versions supported by <B>javac</B> are:
<P>
<DL>
<DT><B>1.1</B>
<DD>Ensure that generated class files will be compatible with 1.1 and VMs in the Java 2 SDK.
<DT><B>1.2</B>
<DD>Generate class files that will run on VMs in the Java 2 SDK, v 1.2 and later, but will not run on 1.1 VMs. This is the default.
<DT><B>1.3</B>
<DD>Generate class files that will run on VMs in the Java 2 SDK, v 1.3 and later, but will not run on 1.1 or 1.2 VMs.
<DT><B>1.4</B>
<DD>Generate class files that are compatible only with 1.4 VMs. </DD></DL>
<P></P></DD></DL></BLOCKQUOTE>
<P>Steve </P>
<BLOCKQUOTE>
<DL></DL>
<DL><BR><BR><B><I>Stephan Trebels <stephan@ncube.de></I></B> wrote:</DL></BLOCKQUOTE>
<BLOCKQUOTE style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #1010ff 2px solid">My understanding is different: <BR><BR>The JDK 1.4 class file format will not by default be used by javac<BR>(1.4.1). The default - as always - is to generate class files<BR>compatible to the last major rev, so it's 1.3 class files. By default<BR>not even aserts will be recognized.<BR><BR>Stephan<BR><BR><BR>On Wed, 2003-04-23 at 16:54, Gordon Tyler wrote:<BR>> John L. Webber - Jentro AG wrote:<BR>> > As far as the source code is concerned it probably doesn't matter, but <BR>> > anyone using the pre-built jars with a pre-1.4 VM will likely see an <BR>> > exception like this:<BR>> > java.lang.UnsupportedClassVersionError: Test (Unsupported major.minor <BR>> > version 48.0)<BR>> > <BR>> > I'm not sure if this will happen with an external library compiled under <BR>> > 1.4 but run pre-1.4. Does anyone have time to test that -- I have <BR>>
> meetings this morning... ;-(<BR>> <BR>> JDK 1.4 introduced some changes in the class file format, upping the <BR>> class version, hence the exception. Pre-1.4 JVMs will not be able to use <BR>> classes compiled by the 1.4 compiler at all.<BR>> <BR>> Ciao,<BR>> Gordon<BR>-- <BR>Stephan Trebels <STEPHAN@NCUBE.DE>Consultant<BR>company: nCUBE Deutschland GmbH, Hanauer Str. 56, 80992 Munich, Germany<BR>phone: cell:+49 172 8433111 office:+49 89 1498930 fax:+49 89 14989350<BR><BR><BR>_______________________________________________<BR>To control your jdom-interest membership:<BR>http://lists.denveronline.net/mailman/options/jdom-interest/youraddr@yourhost.com</BLOCKQUOTE><p><br><hr size=1>Do you Yahoo!?<br>
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