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| <h2><a name="java">Java</a></h2> |
| <h3>Description</h3> |
| <p>Executes a Java class within the running (Ant) VM or forks another VM if |
| specified.</p> |
| <p> |
| If odd things go wrong when you run this task, set fork="true" to use a new |
| JVM. |
| |
| <p>Note that you cannot interact with a forked VM, the only way to |
| send input to it is via the input and inputstring attributes. Also note that |
| in Ant 1.6, any attempt to read input in the forked VM will receive an |
| EOF (-1). This is a change from Ant 1.5, where such an attempt would block.</p> |
| |
| <h3>Parameters</h3> |
| <table border="1" cellpadding="2" cellspacing="0"> |
| <tr> |
| <td valign="top"><b>Attribute</b></td> |
| <td valign="top"><b>Description</b></td> |
| <td align="center" valign="top"><b>Required</b></td> |
| </tr> |
| <tr> |
| <td valign="top">classname</td> |
| <td valign="top">the Java class to execute.</td> |
| <td align="center" valign="top">Either jar or classname</td> |
| </tr> |
| <tr> |
| <td valign="top">jar</td> |
| <td valign="top">the location of the jar file to execute (must have a |
| Main-Class entry in the manifest). Fork must be set to true if this option is selected.</td> |
| <td align="center" valign="top">Either jar or classname</td> |
| </tr> |
| <tr> |
| <td valign="top">args</td> |
| <td valign="top">the arguments for the class that is |
| executed. <b>deprecated, use nested <code><arg></code> |
| elements instead.</b></td> |
| <td align="center" valign="top">No</td> |
| </tr> |
| <tr> |
| <td valign="top">classpath</td> |
| <td valign="top">the classpath to use.</td> |
| <td align="center" valign="top">No</td> |
| </tr> |
| <tr> |
| <td valign="top">classpathref</td> |
| <td valign="top">the classpath to use, given as <a |
| href="../using.html#references">reference</a> to a PATH defined elsewhere.</td> |
| <td align="center" valign="top">No</td> |
| </tr> |
| <tr> |
| <td valign="top">fork</td> |
| <td valign="top">if enabled triggers the class execution in another VM |
| (disabled by default)</td> |
| <td align="center" valign="top">No</td> |
| </tr> |
| <tr> |
| <td valign="top">spawn</td> |
| <td valign="top">if enabled allows to start a process which will outlive ant.<br/> |
| Requires fork=true, and not compatible |
| with timeout, input, output, error, result attributes.<br/> |
| (disabled by default)</td> |
| <td align="center" valign="top">No</td> |
| </tr> |
| <tr> |
| <td valign="top">jvm</td> |
| <td valign="top">the command used to invoke the Java Virtual Machine, |
| default is 'java'. The command is resolved by java.lang.Runtime.exec(). |
| Ignored if fork is disabled. |
| </td> |
| <td align="center" valign="top">No</td> |
| </tr> |
| <tr> |
| <td valign="top">jvmargs</td> |
| <td valign="top">the arguments to pass to the forked VM (ignored |
| if fork is disabled). <b>deprecated, use nested |
| <code><jvmarg></code> elements instead.</b></td> |
| <td align="center" valign="top">No</td> |
| </tr> |
| <tr> |
| <td valign="top">maxmemory</td> |
| <td valign="top">Max amount of memory to allocate to the forked VM |
| (ignored if fork is disabled)</td> |
| <td align="center" valign="top">No</td> |
| </tr> |
| <tr> |
| <td valign="top">failonerror</td> |
| <td valign="top">Stop the buildprocess if the command exits with a |
| returncode other than 0. Default is "false" (see <a href="#failonerror">note)</a></td> |
| <td align="center" valign="top">No</td> |
| </tr> |
| <tr> |
| <td valign="top">resultproperty</td> |
| <td valign="top">The name of a property in which the return code of the |
| command should be stored. Only of interest if failonerror=false |
| and if fork=true.</td> |
| <td align="center" valign="top">No</td> |
| </tr> |
| <tr> |
| <td valign="top">dir</td> |
| <td valign="top">The directory to invoke the VM in. (ignored if |
| fork is disabled)</td> |
| <td align="center" valign="top">No</td> |
| </tr> |
| <tr> |
| <td valign="top">output</td> |
| <td valign="top">Name of a file to which to write the output. If the error stream |
| is not also redirected to a file or property, it will appear in this output.</td> |
| <td align="center" valign="top">No</td> |
| </tr> |
| <tr> |
| <td valign="top">error</td> |
| <td valign="top">The file to which the standard error of the command should be |
| redirected. </td> |
| <td align="center" valign="top">No</td> |
| </tr> |
| <tr> |
| <td valign="top">logError</td> |
| <td valign="top">This attribute is used when you wish to see error output in Ant's |
| log and you are redirecting output to a file/property. The error |
| output will not be included in the output file/property. If you |
| redirect error with the "error" or "errorProperty" |
| attributes, this will have no effect.</td> |
| <td align="center" valign="top">No</td> |
| </tr> |
| <tr> |
| <td valign="top">append</td> |
| <td valign="top">Whether output and error files should be appended to or overwritten. |
| Defaults to false.</td> |
| <td align="center" valign="top">No</td> |
| </tr> |
| <tr> |
| <td valign="top">outputproperty</td> |
| <td valign="top">The name of a property in which the output of the |
| command should be stored. Unless the error stream is redirected to a separate |
| file or stream, this property will include the error output.</td> |
| <td align="center" valign="top">No</td> |
| </tr> |
| <tr> |
| <td valign="top">errorproperty</td> |
| <td valign="top">The name of a property in which the standard error of the |
| command should be stored.</td> |
| <td align="center" valign="top">No</td> |
| </tr> |
| <tr> |
| <td valign="top">input</td> |
| <td valign="top">A file from which the executed command's standard input |
| is taken. This attribute is mutually exclusive with the |
| inputstring attribute</td> |
| <td align="center" valign="top">No</td> |
| </tr> |
| <tr> |
| <td valign="top">inputstring</td> |
| <td valign="top">A string which serves as the input stream for the |
| executed command. This attribute is mutually exclusive with the |
| input attribute.</td> |
| <td align="center" valign="top">No</td> |
| </tr> |
| <tr> |
| <td valign="top">newenvironment</td> |
| <td valign="top">Do not propagate old environment when new |
| environment variables are specified. Default is "false" |
| (ignored if fork is disabled).</td> |
| <td align="center" valign="top">No</td> |
| </tr> |
| <tr> |
| <td valign="top">timeout</td> |
| <td valign="top">Stop the command if it doesn't finish within the |
| specified time (given in milliseconds). <strong>It is highly |
| recommended to use this feature only if fork is enabled.</strong></td> |
| <td align="center" valign="top">No</td> |
| </tr> |
| </table> |
| <h3>Parameters specified as nested elements</h3> |
| <h4>arg and jvmarg</h4> |
| <p>Use nested <code><arg></code> and <code><jvmarg></code> |
| elements to specify arguments for the Java class and the forked VM respectively. |
| See <a href="../using.html#arg">Command line arguments</a>.</p> |
| <h4>sysproperty</h4> |
| <p>Use nested <code><sysproperty></code> |
| elements to specify system properties required by the class. |
| These properties will be made available to the VM during the execution |
| of the class (either ANT's VM or the forked VM). The attributes |
| for this element are the same as for <a href="exec.html#env">environment |
| variables</a>.</p> |
| |
| <h4>syspropertyset</h4> |
| |
| <p>You can specify a set of properties to be used as system properties |
| with <a href="../CoreTypes/propertyset.html">syspropertyset</a>s.</p> |
| |
| <p><em>since Ant 1.6</em>.</p> |
| |
| <h4>classpath</h4> |
| <p><code>Java</code>'s <i>classpath</i> attribute is a <a |
| href="../using.html#path">PATH like structure</a> and can also be set via a nested |
| <i>classpath</i> element.</p> |
| |
| <h4>bootclasspath</h4> |
| |
| <p>The location of bootstrap class files can be specified using this |
| <a href="../using.html#path">PATH like structure</a> - will be ignored |
| if <i>fork</i> is not <code>true</code> or the target VM doesn't |
| support it (i.e. Java 1.1).</p> |
| |
| <p><em>since Ant 1.6</em>.</p> |
| |
| <h4>env</h4> |
| <p>It is possible to specify environment variables to pass to the |
| forked VM via nested <i>env</i> elements. See the description in the |
| section about <a href="exec.html#env">exec</a></p> |
| <p>Settings will be ignored if fork is disabled.</p> |
| |
| <h4>permissions</h4> |
| <p>Security permissions can be revoked and granted during the execution of the |
| class via a nested <i>permissions</i> element. For more information please |
| see <a href="../CoreTypes/permissions.html">permissions</a></p> |
| <p>When the permission RuntimePermission exitVM has not been granted (or has |
| been revoked) the System.exit() call will be intercepted |
| and treated like indicated in <i>failonerror</i>.</p> |
| <p><a name="failonerror"/> |
| If you specify <code>failonerror="true"</code> and you do not specify permissions, |
| a set of default permissions will be added to your java invocation making sure that |
| a non zero return code will lead to a <code>BuildException</code>. |
| </p> |
| <p>Settings will be ignored if fork is enabled.</p> |
| |
| <p><em>since Ant 1.6</em>.</p> |
| |
| <h3>Errors and return codes</h3> |
| By default the return code of a <java> is ignored. Alternatively, you can set <code>resultproperty</code> to the name |
| of a property and have it assigned to the result code (barring immutability, |
| of course). |
| When you set <code>failonerror="true"</code>, the only possible value for <code>resultproperty</code> is 0. Any non zero response is treated as an |
| error and would mean the build exits. |
| <p> Similarly, if <code>failonerror="false"</code> and <code>fork="false"</code> |
| , then <code><java></code> <b>must</b> return 0 otherwise the build will exit, as the class was run by the build jvm.</p> |
| |
| <h3>Examples</h3> |
| <pre> |
| <java classname="test.Main"> |
| <arg value="-h"/> |
| <classpath> |
| <pathelement location="dist/test.jar"/> |
| <pathelement path="${java.class.path}"/> |
| </classpath> |
| </java> |
| </pre> |
| Run a class in this JVM with a new jar on the classpath |
| |
| <pre> <java jar="dist/test.jar" |
| fork="true" |
| failonerror="true" |
| maxmemory="128m" |
| > |
| <arg value="-h"/> |
| <classpath> |
| <pathelement location="dist/test.jar"/> |
| <pathelement path="${java.class.path}"/> |
| </classpath> |
| </java> |
| </pre> |
| Run the jar using the manifest supplied entry point, forking (as required), |
| and with a maximum memory of 128MB. Any non zero return code breaks the build. |
| |
| <pre> <java classname="test.Main"/></pre> |
| <pre> <java classname="test.Main" |
| fork="yes" > |
| <sysproperty key="DEBUG" value="true"/> |
| <arg value="-h"/> |
| <jvmarg value="-Xrunhprof:cpu=samples,file=log.txt,depth=3"/> |
| </java> |
| </pre> |
| <strong>Note</strong>: you can not specify the (highly deprecated) MSJVM, "jview.exe" as the |
| JVM, as it takes different parameters for other JVMs, |
| That JVM can be started from <exec> if required. |
| <hr> |
| <p align="center">Copyright © 2000-2003 Apache Software Foundation. All rights |
| Reserved.</p> |
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