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  190. <h1>Frequently Asked Questions</h1>
  191. </td>
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  197. <strong>Questions</strong>
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  202. <tr><td bgcolor="#4C6C8F">
  203. <font color="#ffffff" face="arial,helvetica,sanserif">
  204. <strong>About this FAQ</strong>
  205. </font>
  206. </td></tr>
  207. </table>
  208. <ul>
  209. <li><a href="#latest-version">
  210. Where do I find the latest version of this
  211. document?
  212. </a></li>
  213. <li><a href="#adding-faqs">
  214. How can I contribute to this FAQ?
  215. </a></li>
  216. <li><a href="#creating-faq">
  217. How do you create the HTML version of this
  218. FAQ?
  219. </a></li>
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  221. <table border="0" cellspacing="0" cellpadding="2" width="100%">
  222. <tr><td bgcolor="#4C6C8F">
  223. <font color="#ffffff" face="arial,helvetica,sanserif">
  224. <strong>General</strong>
  225. </font>
  226. </td></tr>
  227. </table>
  228. <ul>
  229. <li><a href="#what-is-ant">
  230. What is Apache Ant?
  231. </a></li>
  232. <li><a href="#ant-name">
  233. Why do you call it Ant?
  234. </a></li>
  235. <li><a href="#history">
  236. Tell us a little bit about Ant's history.
  237. </a></li>
  238. </ul>
  239. <table border="0" cellspacing="0" cellpadding="2" width="100%">
  240. <tr><td bgcolor="#4C6C8F">
  241. <font color="#ffffff" face="arial,helvetica,sanserif">
  242. <strong>Installation</strong>
  243. </font>
  244. </td></tr>
  245. </table>
  246. <ul>
  247. <li><a href="#no-gnu-tar">
  248. I get checksum errors when I try to extract the
  249. <code>tar.gz</code> distribution file. Why?
  250. </a></li>
  251. </ul>
  252. <table border="0" cellspacing="0" cellpadding="2" width="100%">
  253. <tr><td bgcolor="#4C6C8F">
  254. <font color="#ffffff" face="arial,helvetica,sanserif">
  255. <strong>How do I ...</strong>
  256. </font>
  257. </td></tr>
  258. </table>
  259. <ul>
  260. <li><a href="#adding-external-tasks">
  261. How do I add an external task that I've written to the
  262. page "External Tools and Task"?
  263. </a></li>
  264. <li><a href="#passing-cli-args">
  265. How do I pass parameters from the command line to my
  266. build file?
  267. </a></li>
  268. <li><a href="#jikes-switches">
  269. How can I use Jikes-specific command-line
  270. switches?
  271. </a></li>
  272. <li><a href="#shell-redirect-1">
  273. How do I include a &lt; character in my command-line arguments?
  274. </a></li>
  275. <li><a href="#shell-redirect-2">
  276. How do I redirect standard input or standard output
  277. in the <code>&lt;exec&gt;</code> task?
  278. </a></li>
  279. <li><a href="#batch-shell-execute">
  280. How do I execute a batch file or shell script from Ant?
  281. </a></li>
  282. <li><a href="#multi-conditions">
  283. I want to execute a particular target only if
  284. multiple conditions are true.
  285. </a></li>
  286. <li><a href="#encoding">
  287. How can I include national characters like German
  288. umlauts in my build file?
  289. </a></li>
  290. </ul>
  291. <table border="0" cellspacing="0" cellpadding="2" width="100%">
  292. <tr><td bgcolor="#4C6C8F">
  293. <font color="#ffffff" face="arial,helvetica,sanserif">
  294. <strong>It doesn't work (as expected)</strong>
  295. </font>
  296. </td></tr>
  297. </table>
  298. <ul>
  299. <li><a href="#always-recompiles">
  300. Why does Ant always recompile all my Java files?
  301. </a></li>
  302. <li><a href="#defaultexcludes">
  303. I've used a <code>&lt;delete&gt;</code> task to
  304. delete unwanted SourceSafe control files (CVS files, editor
  305. backup files, etc.), but it doesn't seem to work; the files
  306. never get deleted. What's wrong?
  307. </a></li>
  308. <li><a href="#stop-dependency">
  309. I have a target I want to skip if a property is set,
  310. so I have <code>unless="property"</code> as an attribute
  311. of the target, but all the targets this target
  312. depends on are still executed. Why?
  313. </a></li>
  314. <li><a href="#include-order">
  315. In my <code>&lt;fileset&gt;</code>, I've put in an
  316. <code>&lt;exclude&gt;</code> of all files followed by an
  317. <code>&lt;include&gt;</code> of just the files I want, but it
  318. isn't giving me any files at all. What's wrong?
  319. </a></li>
  320. <li><a href="#properties-not-trimmed">
  321. <code>ant</code> failed to build my program via javac
  322. even when I put the needed jars in an external
  323. <code>build.properties</code> file and reference them by
  324. <code>pathelement</code> or <code>classpath refid</code>.
  325. </a></li>
  326. <li><a href="#winzip-lies">
  327. Ant creates WAR files with a lower-case
  328. <code>web-inf</code> or JAR files with a lower-case
  329. <code>meta-inf</code> directory.
  330. </a></li>
  331. </ul>
  332. <table border="0" cellspacing="0" cellpadding="2" width="100%">
  333. <tr><td bgcolor="#4C6C8F">
  334. <font color="#ffffff" face="arial,helvetica,sanserif">
  335. <strong>Ant and IDEs/Editors</strong>
  336. </font>
  337. </td></tr>
  338. </table>
  339. <ul>
  340. <li><a href="#integration">
  341. Is Ant supported by my IDE/Editor?
  342. </a></li>
  343. <li><a href="#emacs-mode">
  344. Why doesn't (X)Emacs/vi/MacOS X's project builder
  345. correctly parse the error messages generated by Ant?
  346. </a></li>
  347. </ul>
  348. <table border="0" cellspacing="0" cellpadding="2" width="100%">
  349. <tr><td bgcolor="#4C6C8F">
  350. <font color="#ffffff" face="arial,helvetica,sanserif">
  351. <strong>Advanced Issues</strong>
  352. </font>
  353. </td></tr>
  354. </table>
  355. <ul>
  356. <li><a href="#dtd">
  357. Is there a DTD that I can use to validate my build
  358. files?
  359. </a></li>
  360. <li><a href="#xml-entity-include">
  361. How do I include an XML snippet in my build file?
  362. </a></li>
  363. <li><a href="#mail-logger">
  364. How do I send an email with the result of my build
  365. process?
  366. </a></li>
  367. <li><a href="#listener-properties">
  368. How do I get at the properties that Ant was running
  369. with from inside BuildListener?
  370. </a></li>
  371. </ul>
  372. <table border="0" cellspacing="0" cellpadding="2" width="100%">
  373. <tr><td bgcolor="#4C6C8F">
  374. <font color="#ffffff" face="arial,helvetica,sanserif">
  375. <strong>Known Problems</strong>
  376. </font>
  377. </td></tr>
  378. </table>
  379. <ul>
  380. <li><a href="#remove-cr">
  381. &lt;chmod&gt; or &lt;exec&gt; doesn't work in Ant
  382. 1.3 on Unix
  383. </a></li>
  384. <li><a href="#javadoc-cannot-execute">
  385. JavaDoc failed: java.io.IOException: javadoc: cannot execute
  386. </a></li>
  387. <li><a href="#delegating-classloader">
  388. &lt;style&gt; or &lt;junit&gt; ignores my
  389. &lt;classpath&gt;
  390. </a></li>
  391. <li><a href="#winxp-jdk14-ant14">
  392. When running Ant 1.4 on Windows XP and JDK 1.4, I get
  393. various errors when trying to <code>&lt;exec&gt;</code>, fork
  394. <code>&lt;java&gt;</code> or access environment
  395. variables.
  396. </a></li>
  397. <li><a href="#1.5-cygwin-sh">
  398. The <code>ant</code> wrapper script of Ant 1.5 fails
  399. for Cygwin if <code>ANT_HOME</code> is set to a Windows style
  400. path.
  401. </a></li>
  402. </ul>
  403. <table border="0" cellspacing="0" cellpadding="2" width="100%">
  404. <tr><td bgcolor="#294563">
  405. <font color="#ffffff" face="arial,helvetica,sanserif">
  406. <strong>Answers</strong>
  407. </font>
  408. </td></tr>
  409. </table>
  410. <a name="latest-version"></a>
  411. <table border="0" cellspacing="0" cellpadding="2" width="100%">
  412. <tr><td bgcolor="#4C6C8F">
  413. <font color="#ffffff" face="arial,helvetica,sanserif">
  414. <strong>
  415. Where do I find the latest version of this
  416. document?
  417. </strong>
  418. </font>
  419. </td></tr>
  420. </table>
  421. <p>The latest version can always be found at Ant's homepage
  422. <a href="http://jakarta.apache.org/ant/faq.html">http://jakarta.apache.org/ant/faq.html</a>.</p>
  423. <br>
  424. <a name="adding-faqs"></a>
  425. <table border="0" cellspacing="0" cellpadding="2" width="100%">
  426. <tr><td bgcolor="#4C6C8F">
  427. <font color="#ffffff" face="arial,helvetica,sanserif">
  428. <strong>
  429. How can I contribute to this FAQ?
  430. </strong>
  431. </font>
  432. </td></tr>
  433. </table>
  434. <p>The page you are looking it is generated from
  435. <a href="http://cvs.apache.org/viewcvs.cgi/~checkout~/jakarta-ant/xdocs/faq.xml">this</a>
  436. document. If you want to add a new question, please submit
  437. a patch against this document to one of Ant's mailing lists;
  438. hopefully, the structure is self-explanatory.</p>
  439. <p>If you don't know how to create a patch, see the patches
  440. section of <a href="http://jakarta.apache.org/site/source.html">this
  441. page</a>.</p>
  442. <br>
  443. <a name="creating-faq"></a>
  444. <table border="0" cellspacing="0" cellpadding="2" width="100%">
  445. <tr><td bgcolor="#4C6C8F">
  446. <font color="#ffffff" face="arial,helvetica,sanserif">
  447. <strong>
  448. How do you create the HTML version of this
  449. FAQ?
  450. </strong>
  451. </font>
  452. </td></tr>
  453. </table>
  454. <p>We use
  455. <a href="http://jakarta.apache.org/velocity/anakia.html">Anakia</a>
  456. to render the HTML version from the original XML file.</p>
  457. <p>The Velocity stylesheets used to process the XML files can
  458. be found in the <code>xdocs/stylesheets</code> subdirectory of
  459. Ant's CVS repository - the build file <code>docs.xml</code> is
  460. used to drive Anakia. This file assumes that you have the
  461. <code>jakarta-site2</code> module checked out from CVS as
  462. well, but if you follow the instruction from Anakia's
  463. homepage, you should get it to work without that. Just make
  464. sure all required jars are in the task's classpath.</p>
  465. <br>
  466. <a name="what-is-ant"></a>
  467. <table border="0" cellspacing="0" cellpadding="2" width="100%">
  468. <tr><td bgcolor="#4C6C8F">
  469. <font color="#ffffff" face="arial,helvetica,sanserif">
  470. <strong>
  471. What is Apache Ant?
  472. </strong>
  473. </font>
  474. </td></tr>
  475. </table>
  476. <p> Ant is a Java-based build tool. In theory, it is kind of
  477. like Make, without Make's wrinkles and with the full
  478. portability of pure Java code.</p>
  479. <br>
  480. <a name="ant-name"></a>
  481. <table border="0" cellspacing="0" cellpadding="2" width="100%">
  482. <tr><td bgcolor="#4C6C8F">
  483. <font color="#ffffff" face="arial,helvetica,sanserif">
  484. <strong>
  485. Why do you call it Ant?
  486. </strong>
  487. </font>
  488. </td></tr>
  489. </table>
  490. <p>According to Ant's original author, James Duncan
  491. Davidson, the name is an acronym for "Another Neat
  492. Tool".</p>
  493. <p>Later explanations go along the lines of "ants
  494. do an extremely good job at building things", or
  495. "ants are very small and can carry a weight dozens of times
  496. their own" - describing what Ant is intended to
  497. be.</p>
  498. <br>
  499. <a name="history"></a>
  500. <table border="0" cellspacing="0" cellpadding="2" width="100%">
  501. <tr><td bgcolor="#4C6C8F">
  502. <font color="#ffffff" face="arial,helvetica,sanserif">
  503. <strong>
  504. Tell us a little bit about Ant's history.
  505. </strong>
  506. </font>
  507. </td></tr>
  508. </table>
  509. <p>Initially, Ant was part of the Tomcat code base, when it was
  510. donated to the Apache Software Foundation. It was
  511. created by James Duncan Davidson, who is also the original
  512. author of Tomcat. Ant was there to build Tomcat, nothing
  513. else.</p>
  514. <p>Soon thereafter, several open source Java projects realized
  515. that Ant could solve the problems they had with Makefiles.
  516. Starting with the projects hosted at Jakarta and the old Java
  517. Apache project, Ant spread like a virus and is now the build
  518. tool of choice for a lot of projects.</p>
  519. <p>In January 2000, Ant was moved to a separate CVS module and
  520. was promoted to a project of its own, independent of
  521. Tomcat, and became Apache Ant.</p>
  522. <p>The first version of Ant that was exposed to a larger audience
  523. was the one that shipped with Tomcat's 3.1 release on 19 April
  524. 2000. This version has later been referred to as Ant
  525. 0.3.1.</p>
  526. <p>The first official release of Ant as a stand-alone product was
  527. Ant 1.1, released on 19 July 2000. The complete release
  528. history:</p>
  529. <table class="ForrestTable" cellspacing="1" cellpadding="4">
  530. <tr>
  531. <th colspan="1" rowspan="1"
  532. valign="top" align="left">
  533. Ant Version
  534. </th>
  535. <th colspan="1" rowspan="1"
  536. valign="top" align="left">
  537. Release Date
  538. </th>
  539. </tr>
  540. <tr>
  541. <td colspan="1" rowspan="1"
  542. valign="top" align="left">
  543. 1.1
  544. </td>
  545. <td colspan="1" rowspan="1"
  546. valign="top" align="left">
  547. 19 July 2000
  548. </td>
  549. </tr>
  550. <tr>
  551. <td colspan="1" rowspan="1"
  552. valign="top" align="left">
  553. 1.2
  554. </td>
  555. <td colspan="1" rowspan="1"
  556. valign="top" align="left">
  557. 24 October 2000
  558. </td>
  559. </tr>
  560. <tr>
  561. <td colspan="1" rowspan="1"
  562. valign="top" align="left">
  563. 1.3
  564. </td>
  565. <td colspan="1" rowspan="1"
  566. valign="top" align="left">
  567. 3 March 2001
  568. </td>
  569. </tr>
  570. <tr>
  571. <td colspan="1" rowspan="1"
  572. valign="top" align="left">
  573. 1.4
  574. </td>
  575. <td colspan="1" rowspan="1"
  576. valign="top" align="left">
  577. 3 September 2001
  578. </td>
  579. </tr>
  580. <tr>
  581. <td colspan="1" rowspan="1"
  582. valign="top" align="left">
  583. 1.4.1
  584. </td>
  585. <td colspan="1" rowspan="1"
  586. valign="top" align="left">
  587. 11 October 2001
  588. </td>
  589. </tr>
  590. <tr>
  591. <td colspan="1" rowspan="1"
  592. valign="top" align="left">
  593. 1.5
  594. </td>
  595. <td colspan="1" rowspan="1"
  596. valign="top" align="left">
  597. 10 July 2002
  598. </td>
  599. </tr>
  600. <tr>
  601. <td colspan="1" rowspan="1"
  602. valign="top" align="left">
  603. 1.5.1
  604. </td>
  605. <td colspan="1" rowspan="1"
  606. valign="top" align="left">
  607. 3 October 2002
  608. </td>
  609. </tr>
  610. </table>
  611. <br>
  612. <a name="no-gnu-tar"></a>
  613. <table border="0" cellspacing="0" cellpadding="2" width="100%">
  614. <tr><td bgcolor="#4C6C8F">
  615. <font color="#ffffff" face="arial,helvetica,sanserif">
  616. <strong>
  617. I get checksum errors when I try to extract the
  618. <code>tar.gz</code> distribution file. Why?
  619. </strong>
  620. </font>
  621. </td></tr>
  622. </table>
  623. <p>Ant's distribution contains file names that are longer
  624. than 100 characters, which is not supported by the standard
  625. tar file format. Several different implementations of tar use
  626. different and incompatible ways to work around this
  627. restriction.</p>
  628. <p>Ant's &lt;tar&gt; task can create tar archives that use
  629. the GNU tar extension, and this has been used when putting
  630. together the distribution. If you are using a different
  631. version of tar (for example, the one shipping with Solaris),
  632. you cannot use it to extract the archive.</p>
  633. <p>The solution is to either install GNU tar, which can be
  634. found <a href="http://www.gnu.org/software/tar/tar.html">here</a>,
  635. or use the zip archive instead (you can extract it using
  636. <code>jar xf</code>).</p>
  637. <br>
  638. <a name="adding-external-tasks"></a>
  639. <table border="0" cellspacing="0" cellpadding="2" width="100%">
  640. <tr><td bgcolor="#4C6C8F">
  641. <font color="#ffffff" face="arial,helvetica,sanserif">
  642. <strong>
  643. How do I add an external task that I've written to the
  644. page "External Tools and Task"?
  645. </strong>
  646. </font>
  647. </td></tr>
  648. </table>
  649. <p>Join and post a message to the ant-dev or ant-user mailing
  650. list (one list is enough), including the following
  651. information:</p>
  652. <ul>
  653. <li>the name of the task/tool</li>
  654. <li>a short description of the task/tool</li>
  655. <li>a Compatibility: entry stating with which version(s) of
  656. Ant the tool/task is compatible to</li>
  657. <li>a URL: entry linking to the main page of the tool/task</li>
  658. <li>a Contact: entry containing the email address or the URL
  659. of a webpage for the person or list to contact for issues
  660. related to the tool/task. <strong>Note that we'll add a
  661. link on the page, so any email address added there is not
  662. obfuscated and can (and probably will) be abused by robots
  663. harvesting websites for addresses to spam.</strong></li>
  664. <li>a License: entry containing the type of license for the
  665. tool/task</li>
  666. </ul>
  667. <p>The preferred format for this information is a patch to <a href="http://cvs.apache.org/viewcvs.cgi/~checkout~/jakarta-ant/xdocs/external.xml">this</a>
  668. document.</p>
  669. <br>
  670. <a name="passing-cli-args"></a>
  671. <table border="0" cellspacing="0" cellpadding="2" width="100%">
  672. <tr><td bgcolor="#4C6C8F">
  673. <font color="#ffffff" face="arial,helvetica,sanserif">
  674. <strong>
  675. How do I pass parameters from the command line to my
  676. build file?
  677. </strong>
  678. </font>
  679. </td></tr>
  680. </table>
  681. <p>Use properties. Using <code>ant
  682. -D<em>name</em>=<em>value</em></code> lets you define values for
  683. properties on the Ant command line. These properties can then be
  684. used within your build file as
  685. any normal property: <code>${<em>name</em>}</code> will put in
  686. <code><em>value</em></code>.</p>
  687. <br>
  688. <a name="jikes-switches"></a>
  689. <table border="0" cellspacing="0" cellpadding="2" width="100%">
  690. <tr><td bgcolor="#4C6C8F">
  691. <font color="#ffffff" face="arial,helvetica,sanserif">
  692. <strong>
  693. How can I use Jikes-specific command-line
  694. switches?
  695. </strong>
  696. </font>
  697. </td></tr>
  698. </table>
  699. <p>A couple of switches are supported via "magic"
  700. properties:</p>
  701. <table class="ForrestTable" cellspacing="1" cellpadding="4">
  702. <tr>
  703. <th colspan="1" rowspan="1"
  704. valign="top" align="left">
  705. switch
  706. </th>
  707. <th colspan="1" rowspan="1"
  708. valign="top" align="left">
  709. property
  710. </th>
  711. <th colspan="1" rowspan="1"
  712. valign="top" align="left">
  713. default
  714. </th>
  715. </tr>
  716. <tr>
  717. <td colspan="1" rowspan="1"
  718. valign="top" align="left">
  719. +E
  720. </td>
  721. <td colspan="1" rowspan="1"
  722. valign="top" align="left">
  723. build.compiler.emacs
  724. </td>
  725. <td colspan="1" rowspan="1"
  726. valign="top" align="left">
  727. false == not set
  728. </td>
  729. </tr>
  730. <tr>
  731. <td colspan="1" rowspan="1"
  732. valign="top" align="left">
  733. +P
  734. </td>
  735. <td colspan="1" rowspan="1"
  736. valign="top" align="left">
  737. build.compiler.pedantic
  738. </td>
  739. <td colspan="1" rowspan="1"
  740. valign="top" align="left">
  741. false == not set
  742. </td>
  743. </tr>
  744. <tr>
  745. <td colspan="1" rowspan="1"
  746. valign="top" align="left">
  747. +F
  748. </td>
  749. <td colspan="1" rowspan="1"
  750. valign="top" align="left">
  751. build.compiler.fulldepend
  752. </td>
  753. <td colspan="1" rowspan="1"
  754. valign="top" align="left">
  755. false == not set
  756. </td>
  757. </tr>
  758. <tr>
  759. <td colspan="1" rowspan="1"
  760. valign="top" align="left">
  761. <strong>(Only for Ant &lt; 1.4; replaced by the
  762. <code><strong>nowarn</strong></code>
  763. attribute of the <code><strong>&lt;javac&gt;</strong></code>
  764. task after that.)</strong><br />-nowarn
  765. </td>
  766. <td colspan="1" rowspan="1"
  767. valign="top" align="left">
  768. build.compiler.warnings
  769. </td>
  770. <td colspan="1" rowspan="1"
  771. valign="top" align="left">
  772. true == not set
  773. </td>
  774. </tr>
  775. </table>
  776. <p>With Ant &gt;= 1.5, you can also use nested
  777. <code>&lt;compilerarg&gt;</code> elements with the
  778. <code>&lt;javac&gt;</code> task.</p>
  779. <br>
  780. <a name="shell-redirect-1"></a>
  781. <table border="0" cellspacing="0" cellpadding="2" width="100%">
  782. <tr><td bgcolor="#4C6C8F">
  783. <font color="#ffffff" face="arial,helvetica,sanserif">
  784. <strong>
  785. How do I include a &lt; character in my command-line arguments?
  786. </strong>
  787. </font>
  788. </td></tr>
  789. </table>
  790. <p>The short answer is "Use: <code>&amp;lt;</code>".</p>
  791. <p>The long answer is that this probably won't do what you
  792. want anyway (see <a href="#shell-redirect-2">the next
  793. section</a>).</p>
  794. <br>
  795. <a name="shell-redirect-2"></a>
  796. <table border="0" cellspacing="0" cellpadding="2" width="100%">
  797. <tr><td bgcolor="#4C6C8F">
  798. <font color="#ffffff" face="arial,helvetica,sanserif">
  799. <strong>
  800. How do I redirect standard input or standard output
  801. in the <code>&lt;exec&gt;</code> task?
  802. </strong>
  803. </font>
  804. </td></tr>
  805. </table>
  806. <p>Say you want to redirect the standard input stream of the
  807. <code>cat</code> command to read from a file, something
  808. like:</p>
  809. <pre class="code">
  810. shell-prompt&gt; cat &lt; foo
  811. </pre>
  812. <p>and try to translate it into</p>
  813. <pre class="code">
  814. &lt;exec executable=&quot;cat&quot;&gt;
  815. &lt;arg value=&quot;&amp;lt;&quot; /&gt;
  816. &lt;arg value=&quot;foo&quot; /&gt;
  817. &lt;/exec&gt;
  818. </pre>
  819. <p>This will not do what you expect. The input redirection is
  820. performed by your shell, not the command itself, so this
  821. should read:</p>
  822. <pre class="code">
  823. &lt;exec executable=&quot;/bin/sh&quot;&gt;
  824. &lt;arg value=&quot;-c&quot; /&gt;
  825. &lt;arg value=&quot;cat &amp;lt; foo&quot; /&gt;
  826. &lt;/exec&gt;
  827. </pre>
  828. <p>Note that you must use the <code>value</code> attribute of
  829. <code>&lt;arg&gt;</code> in the last element, in order to have
  830. the command passed as a single, quoted argument. Alternatively,
  831. you can use:</p>
  832. <pre class="code">
  833. &lt;exec executable=&quot;/bin/sh&quot;&gt;
  834. &lt;arg line='-c &quot;cat &amp;lt; foo&quot;'/&gt;
  835. &lt;/exec&gt;
  836. </pre>
  837. <p>Note the double-quotes nested inside the single-quotes.</p>
  838. <br>
  839. <a name="batch-shell-execute"></a>
  840. <table border="0" cellspacing="0" cellpadding="2" width="100%">
  841. <tr><td bgcolor="#4C6C8F">
  842. <font color="#ffffff" face="arial,helvetica,sanserif">
  843. <strong>
  844. How do I execute a batch file or shell script from Ant?
  845. </strong>
  846. </font>
  847. </td></tr>
  848. </table>
  849. <p>On native Unix systems, you should be able to run shell scripts
  850. directly. On systems running a Unix-type shell (for example, Cygwin
  851. on Windows) execute the (command) shell instead - <code>cmd</code>
  852. for batch files, <code>sh</code> for shell scripts - then pass the
  853. batch file or shell script (plus any arguments to the script)
  854. as a single command, using the <code>/c</code> or
  855. <code>-c</code> switch, respectively. See
  856. <a href="#shell-redirect-2">the above section</a>
  857. for example <code>&lt;exec&gt;</code> tasks
  858. executing <code>sh</code>. For batch files, use something like:</p>
  859. <pre class="code">
  860. &lt;exec dir=&quot;.&quot; executable=&quot;cmd&quot; os=&quot;Windows NT&quot;&gt;
  861. &lt;arg line=&quot;/c test.bat&quot;/&gt;
  862. &lt;/exec&gt;
  863. </pre>
  864. <br>
  865. <a name="multi-conditions"></a>
  866. <table border="0" cellspacing="0" cellpadding="2" width="100%">
  867. <tr><td bgcolor="#4C6C8F">
  868. <font color="#ffffff" face="arial,helvetica,sanserif">
  869. <strong>
  870. I want to execute a particular target only if
  871. multiple conditions are true.
  872. </strong>
  873. </font>
  874. </td></tr>
  875. </table>
  876. <p>There are actually several answers to this question.</p>
  877. <p>If you have only one set and one unset property to test,
  878. you can specify both an <code>if</code> and an <code>unless</code>
  879. attribute for the target, and they will act as if they
  880. are "anded" together.</p>
  881. <p>If you are using a version of Ant 1.3 or earlier, the
  882. way to work with all other cases is to chain targets together
  883. to determine the specific state you want to test for.</p>
  884. <p>To see how this works, assume you have three properties:
  885. <code>prop1</code>, <code>prop2</code>, and <code>prop3</code>.
  886. You want to test that <code>prop1</code> and <code>prop2</code>
  887. are set, and that <code>prop3</code> is not. If the condition
  888. holds true you want to echo "yes".</p>
  889. <p>Here is the implementation in Ant 1.3 and earlier:</p>
  890. <pre class="code">
  891. &lt;target name=&quot;cond&quot; depends=&quot;cond-if&quot;/&gt;
  892. &lt;target name=&quot;cond-if&quot; if=&quot;prop1&quot;&gt;
  893. &lt;antcall target=&quot;cond-if-2&quot;/&gt;
  894. &lt;/target&gt;
  895. &lt;target name=&quot;cond-if-2&quot; if=&quot;prop2&quot;&gt;
  896. &lt;antcall target=&quot;cond-if-3&quot;/&gt;
  897. &lt;/target&gt;
  898. &lt;target name=&quot;cond-if-3&quot; unless=&quot;prop3&quot;&gt;
  899. &lt;echo message=&quot;yes&quot;/&gt;
  900. &lt;/target&gt;
  901. </pre>
  902. <p>Note: <code>&lt;antcall&gt;</code> tasks do <em>not</em> pass
  903. property changes back up to the environment they were called
  904. from, so you would'nt be able to, for example, set a
  905. <code>result</code> property in the <code>cond-if-3</code> target,
  906. then do
  907. <code>&lt;echo message="result is ${result}"/&gt;</code>
  908. in the <code>cond</code> target.</p>
  909. <p>Starting with Ant 1.4, you can use the
  910. <code>&lt;condition&gt;</code> task.</p>
  911. <pre class="code">
  912. &lt;target name=&quot;cond&quot; depends=&quot;cond-if,cond-else&quot;/&gt;
  913. &lt;target name=&quot;check-cond&quot;&gt;
  914. &lt;condition property=&quot;cond-is-true&quot;&gt;
  915. &lt;and&gt;
  916. &lt;not&gt;
  917. &lt;equals arg1=&quot;${prop1}&quot; arg2=&quot;$${prop1}&quot; /&gt;
  918. &lt;/not&gt;
  919. &lt;not&gt;
  920. &lt;equals arg1=&quot;${prop2}&quot; arg2=&quot;$${prop2}&quot; /&gt;
  921. &lt;/not&gt;
  922. &lt;equals arg1=&quot;${prop3}&quot; arg2=&quot;$${prop3}&quot; /&gt;
  923. &lt;/and&gt;
  924. &lt;/condition&gt;
  925. &lt;/target&gt;
  926. &lt;target name=&quot;cond-if&quot; depends=&quot;check-cond&quot; if=&quot;cond-is-true&quot;&gt;
  927. &lt;echo message=&quot;yes&quot;/&gt;
  928. &lt;/target&gt;
  929. &lt;target name=&quot;cond-else&quot; depends=&quot;check-cond&quot; unless=&quot;cond-is-true&quot;&gt;
  930. &lt;echo message=&quot;no&quot;/&gt;
  931. &lt;/target&gt;
  932. </pre>
  933. <p>This version takes advantage of two things:</p>
  934. <ul>
  935. <li>If a property <code>a</code> has not been set,
  936. <code>${a}</code> will evaluate to <code>${a}</code>.</li>
  937. <li>To get a literal <code>$</code> in Ant, you have to
  938. escape it with another <code>$</code> - this will also break
  939. the special treatment of the <code>${</code> sequence.</li>
  940. </ul>
  941. <p>Because testing for a literal <code>${property}</code> string
  942. isn't all that readable or easy to understand,
  943. post-1.4.1 Ant introduces the <code>&lt;isset&gt;</code> element
  944. to the <code>&lt;condition&gt;</code> task.</p>
  945. <p>Here is the previous example done using
  946. <code>&lt;isset&gt;</code>:</p>
  947. <pre class="code">
  948. &lt;target name=&quot;check-cond&quot;&gt;
  949. &lt;condition property=&quot;cond-is-true&quot;&gt;
  950. &lt;and&gt;
  951. &lt;isset property=&quot;prop1&quot;/&gt;
  952. &lt;isset property=&quot;prop2&quot;/&gt;
  953. &lt;not&gt;
  954. &lt;isset property=&quot;prop3&quot;/&gt;
  955. &lt;/not&gt;
  956. &lt;/and&gt;
  957. &lt;/condition&gt;
  958. &lt;/target&gt;
  959. </pre>
  960. <p>The last option is to use a scripting language to set the
  961. properties. This can be particularly handy when you need much
  962. finer control than the simple conditions shown here but, of
  963. course, comes with the overhead of adding JAR files to support
  964. the language, to say nothing of the added maintenance in requiring
  965. two languages to implement a single system. See the
  966. <a href="manual/OptionalTasks/script.html">
  967. <code>&lt;script&gt;</code> task documentation</a> for more
  968. details.</p>
  969. <br>
  970. <a name="encoding"></a>
  971. <table border="0" cellspacing="0" cellpadding="2" width="100%">
  972. <tr><td bgcolor="#4C6C8F">
  973. <font color="#ffffff" face="arial,helvetica,sanserif">
  974. <strong>
  975. How can I include national characters like German
  976. umlauts in my build file?
  977. </strong>
  978. </font>
  979. </td></tr>
  980. </table>
  981. <p>You need to tell the XML parser which character encoding
  982. your build file uses, this is done inside the <a href="http://www.w3.org/TR/2000/REC-xml-20001006#sec-prolog-dtd">XML
  983. declaration</a>.</p>
  984. <p>By default the parser assumes you are using the UTF-8
  985. encoding instead of your platform's default. For most Western
  986. European countries you should set the encoding to
  987. <code>ISO-8859-1</code>. To do so, make the very first line
  988. of you build file read like</p>
  989. <pre class="code">
  990. &lt;?xml version=&quot;1.0&quot; encoding=&quot;ISO-8859-1&quot; ?&gt;
  991. </pre>
  992. <br>
  993. <a name="always-recompiles"></a>
  994. <table border="0" cellspacing="0" cellpadding="2" width="100%">
  995. <tr><td bgcolor="#4C6C8F">
  996. <font color="#ffffff" face="arial,helvetica,sanserif">
  997. <strong>
  998. Why does Ant always recompile all my Java files?
  999. </strong>
  1000. </font>
  1001. </td></tr>
  1002. </table>
  1003. <p>In order to find out which files should be compiled, Ant
  1004. compares the timestamps of the source files to those of the
  1005. resulting <code>.class</code> files. Opening all source files
  1006. to find out which package they belong to would be very
  1007. inefficient. Instead, Ant expects you to place your
  1008. source files in a directory hierarchy that mirrors your
  1009. package hierarchy and to point Ant to the root of this
  1010. directory tree with the <code>srcdir</code> attribute.</p>
  1011. <p>Say you have <code>&lt;javac srcdir="src"
  1012. destdir="dest"/&gt;</code>. If Ant finds a file
  1013. <code>src/a/b/C.java</code>, it expects it to be in package
  1014. <code>a.b</code> so that the resulting <code>.class</code>
  1015. file is going to be <code>dest/a/b/C.class</code>.</p>
  1016. <p>If your source-tree directory structure does not match your
  1017. package structure, Ant's heuristic won't work, and
  1018. it will recompile classes that are up-to-date. Ant is not the
  1019. only tool that expects a source-tree layout like this.</p>
  1020. <p>If you have Java source files that aren't declared to
  1021. be part of any package, you can still use the <code>&lt;javac&gt;</code>
  1022. task to compile these files correctly - just set the
  1023. <code>srcdir</code> and <code>destdir</code> attributes to
  1024. the actual directory the source
  1025. files live in and the directory the class files should go into,
  1026. respectively.</p>
  1027. <br>
  1028. <a name="defaultexcludes"></a>
  1029. <table border="0" cellspacing="0" cellpadding="2" width="100%">
  1030. <tr><td bgcolor="#4C6C8F">
  1031. <font color="#ffffff" face="arial,helvetica,sanserif">
  1032. <strong>
  1033. I've used a <code>&lt;delete&gt;</code> task to
  1034. delete unwanted SourceSafe control files (CVS files, editor
  1035. backup files, etc.), but it doesn't seem to work; the files
  1036. never get deleted. What's wrong?
  1037. </strong>
  1038. </font>
  1039. </td></tr>
  1040. </table>
  1041. <p>This is probably happening because, by default, Ant excludes
  1042. SourceSafe control files (<code>vssver.scc</code>) and certain other
  1043. files from FileSets.</p>
  1044. <p>Here's what you probably did:</p>
  1045. <pre class="code">
  1046. &lt;delete&gt;
  1047. &lt;fileset dir=&quot;${build.src}&quot; includes=&quot;**/vssver.scc&quot;/&gt;
  1048. &lt;/delete&gt;
  1049. </pre>
  1050. <p>You need to switch off the default exclusions,
  1051. and it will work:</p>
  1052. <pre class="code">
  1053. &lt;delete&gt;
  1054. &lt;fileset dir=&quot;${build.src}&quot; includes=&quot;**/vssver.scc&quot;
  1055. defaultexcludes=&quot;no&quot;/&gt;
  1056. &lt;/delete&gt;
  1057. </pre>
  1058. <p>For a complete listing of the patterns that are excluded
  1059. by default, see <a href="manual/dirtasks.html#defaultexcludes">the user
  1060. manual</a>.</p>
  1061. <br>
  1062. <a name="stop-dependency"></a>
  1063. <table border="0" cellspacing="0" cellpadding="2" width="100%">
  1064. <tr><td bgcolor="#4C6C8F">
  1065. <font color="#ffffff" face="arial,helvetica,sanserif">
  1066. <strong>
  1067. I have a target I want to skip if a property is set,
  1068. so I have <code>unless="property"</code> as an attribute
  1069. of the target, but all the targets this target
  1070. depends on are still executed. Why?
  1071. </strong>
  1072. </font>
  1073. </td></tr>
  1074. </table>
  1075. <p>The list of dependencies is generated by Ant before any of the
  1076. targets are run. This allows dependent targets, such as an
  1077. <code>init</code> target, to set properties that can control the
  1078. execution of the targets higher in the dependency graph. This
  1079. is a good thing.</p>
  1080. <p>However, when your dependencies break down the
  1081. higher-level task
  1082. into several smaller steps, this behaviour becomes
  1083. counter-intuitive. There are a couple of solutions available:
  1084. </p>
  1085. <ol>
  1086. <li>Put the same condition on each of the dependent targets.</li>
  1087. <li>Execute the steps using <code>&lt;antcall&gt;</code>,
  1088. instead of specifying them inside the <code>depends</code>
  1089. attribute.</li>
  1090. </ol>
  1091. <br>
  1092. <a name="include-order"></a>
  1093. <table border="0" cellspacing="0" cellpadding="2" width="100%">
  1094. <tr><td bgcolor="#4C6C8F">
  1095. <font color="#ffffff" face="arial,helvetica,sanserif">
  1096. <strong>
  1097. In my <code>&lt;fileset&gt;</code>, I've put in an
  1098. <code>&lt;exclude&gt;</code> of all files followed by an
  1099. <code>&lt;include&gt;</code> of just the files I want, but it
  1100. isn't giving me any files at all. What's wrong?
  1101. </strong>
  1102. </font>
  1103. </td></tr>
  1104. </table>
  1105. <p>The order of the <code>&lt;include&gt;</code> and
  1106. <code>&lt;exclude&gt;</code> tags within a <code>&lt;fileset&gt;</code>
  1107. is ignored when the FileSet is created. Instead, all of the
  1108. <code>&lt;include&gt;</code> elements are processed together,
  1109. followed by all of the <code>&lt;exclude&gt;</code>
  1110. elements. This means that the <code>&lt;exclude&gt;</code>
  1111. elements only apply to the file list produced by the
  1112. <code>&lt;include&gt;</code> elements.</p>
  1113. <p>To get the files you want, focus on just the
  1114. <code>&lt;include&gt;</code> patterns that would be necessary
  1115. to get them. If you find you need to trim the list that the
  1116. <code>&lt;include&gt;</code> elements produce, then use
  1117. <code>&lt;exclude&gt;</code> elements.</p>
  1118. <br>
  1119. <a name="properties-not-trimmed"></a>
  1120. <table border="0" cellspacing="0" cellpadding="2" width="100%">
  1121. <tr><td bgcolor="#4C6C8F">
  1122. <font color="#ffffff" face="arial,helvetica,sanserif">
  1123. <strong>
  1124. <code>ant</code> failed to build my program via javac
  1125. even when I put the needed jars in an external
  1126. <code>build.properties</code> file and reference them by
  1127. <code>pathelement</code> or <code>classpath refid</code>.
  1128. </strong>
  1129. </font>
  1130. </td></tr>
  1131. </table>
  1132. <p>When <code>ant</code> loads properties from an external
  1133. file it dosn't touch the value of properties, trailing blanks
  1134. will not be trimmed for example.</p>
  1135. <p>If the value represents a file path, like a jar needed to
  1136. compile, the task which requires the value, javac for example
  1137. would fail to compile since it can't find the file due to
  1138. trailing spaces.</p>
  1139. <br>
  1140. <a name="winzip-lies"></a>
  1141. <table border="0" cellspacing="0" cellpadding="2" width="100%">
  1142. <tr><td bgcolor="#4C6C8F">
  1143. <font color="#ffffff" face="arial,helvetica,sanserif">
  1144. <strong>
  1145. Ant creates WAR files with a lower-case
  1146. <code>web-inf</code> or JAR files with a lower-case
  1147. <code>meta-inf</code> directory.
  1148. </strong>
  1149. </font>
  1150. </td></tr>
  1151. </table>
  1152. <p>No it doesn't.</p>
  1153. <p>You may have seen these lower-case directory names in
  1154. WinZIP, but WinZIP is trying to be helpful (and fails). If
  1155. WinZIP encounters a filename that is all upper-case, it
  1156. assumes it has come from an old DOS box andchanges the case to
  1157. all lower-case for you.</p>
  1158. <p>If you extract (or just check) the archive with jar, you
  1159. will see that the names have the correct case.</p>
  1160. <br>
  1161. <a name="integration"></a>
  1162. <table border="0" cellspacing="0" cellpadding="2" width="100%">
  1163. <tr><td bgcolor="#4C6C8F">
  1164. <font color="#ffffff" face="arial,helvetica,sanserif">
  1165. <strong>
  1166. Is Ant supported by my IDE/Editor?
  1167. </strong>
  1168. </font>
  1169. </td></tr>
  1170. </table>
  1171. <p>See the <a href="external.html#IDE and Editor Integration">section
  1172. on IDE integration</a> on our External Tools and Tasks page.</p>
  1173. <br>
  1174. <a name="emacs-mode"></a>
  1175. <table border="0" cellspacing="0" cellpadding="2" width="100%">
  1176. <tr><td bgcolor="#4C6C8F">
  1177. <font color="#ffffff" face="arial,helvetica,sanserif">
  1178. <strong>
  1179. Why doesn't (X)Emacs/vi/MacOS X's project builder
  1180. correctly parse the error messages generated by Ant?
  1181. </strong>
  1182. </font>
  1183. </td></tr>
  1184. </table>
  1185. <p>Ant adds a "banner" with the name of the current
  1186. task in front of all logging messages - and there are no built-in
  1187. regular expressions in your editor that would account for
  1188. this.</p>
  1189. <p>You can disable this banner by invoking Ant with the
  1190. <code>-emacs</code> switch. To make Ant autodetect
  1191. Emacs' compile mode, put this into your
  1192. <code>.antrc</code> (contributed by Ville Skytt).</p>
  1193. <pre class="code">
  1194. # Detect (X)Emacs compile mode
  1195. if [ &quot;$EMACS&quot; = &quot;t&quot; ] ; then
  1196. ANT_ARGS=&quot;$ANT_ARGS -emacs&quot;
  1197. ANT_OPTS=&quot;$ANT_OPTS -Dbuild.compiler.emacs=true&quot;
  1198. fi
  1199. </pre>
  1200. <p>Alternatively, you can add the following snippet to your
  1201. <code>.emacs</code> to make Emacs understand Ant's
  1202. output.</p>
  1203. <pre class="code">
  1204. (require 'compile)
  1205. (setq compilation-error-regexp-alist
  1206. (append (list
  1207. ;; works for jikes
  1208. '(&quot;^\\s-*\\[[^]]*\\]\\s-*\\(.+\\):\\([0-9]+\\):\\([0-9]+\\):[0-9]+:[0-9]+:&quot; 1 2 3)
  1209. ;; works for javac
  1210. '(&quot;^\\s-*\\[[^]]*\\]\\s-*\\(.+\\):\\([0-9]+\\):&quot; 1 2))
  1211. compilation-error-regexp-alist))
  1212. </pre>
  1213. <p>Yet another alternative that preserves most of Ant's
  1214. formatting is to pipe Ant's output through the following Perl
  1215. script by Dirk-Willem van Gulik:</p>
  1216. <pre class="code">
  1217. #!/usr/bin/perl
  1218. #
  1219. # May 2001 dirkx@apache.org - remove any
  1220. # [foo] lines from the output; keeping
  1221. # spacing more or less there.
  1222. #
  1223. $|=1;
  1224. while(&lt;STDIN&gt;) {
  1225. if (s/^(\s+)\[(\w+)\]//) {
  1226. if ($2 ne $last) {
  1227. print &quot;$1\[$2\]&quot;;
  1228. $s = ' ' x length($2);
  1229. } else {
  1230. print &quot;$1 $s &quot;;
  1231. };
  1232. $last = $2;
  1233. };
  1234. print;
  1235. };
  1236. </pre>
  1237. <br>
  1238. <a name="dtd"></a>
  1239. <table border="0" cellspacing="0" cellpadding="2" width="100%">
  1240. <tr><td bgcolor="#4C6C8F">
  1241. <font color="#ffffff" face="arial,helvetica,sanserif">
  1242. <strong>
  1243. Is there a DTD that I can use to validate my build
  1244. files?
  1245. </strong>
  1246. </font>
  1247. </td></tr>
  1248. </table>
  1249. <p>An incomplete DTD can be created by the
  1250. <code>&lt;antstructure&gt;</code> task - but this one
  1251. has a few problems:</p>
  1252. <ul>
  1253. <li>It doesn't know about required attributes. Only
  1254. manual tweaking of this file can help here.</li>
  1255. <li>It is not complete - if you add new tasks via
  1256. <code>&lt;taskdef&gt;</code> it won't know about it. See
  1257. <a href="http://www.sdv.fr/pages/casa/html/ant-dtd.en.html">this
  1258. page</a> by Michel Casabianca for a solution to this
  1259. problem. Note that the DTD you can download at this page
  1260. is based on Ant 0.3.1.</li>
  1261. <li>It may even be an invalid DTD. As Ant allows tasks
  1262. writers to define arbitrary elements, name collisions will
  1263. happen quite frequently - if your version of Ant contains
  1264. the optional <code>&lt;test&gt;</code> and
  1265. <code>&lt;junit&gt;</code> tasks, there are two XML
  1266. elements named <code>test</code> (the task and the nested child
  1267. element of <code>&lt;junit&gt;</code>) with different attribute
  1268. lists. This problem cannot be solved; DTDs don't give a
  1269. syntax rich enough to support this.</li>
  1270. </ul>
  1271. <br>
  1272. <a name="xml-entity-include"></a>
  1273. <table border="0" cellspacing="0" cellpadding="2" width="100%">
  1274. <tr><td bgcolor="#4C6C8F">
  1275. <font color="#ffffff" face="arial,helvetica,sanserif">
  1276. <strong>
  1277. How do I include an XML snippet in my build file?
  1278. </strong>
  1279. </font>
  1280. </td></tr>
  1281. </table>
  1282. <p>You can use XML's way of including external files and let
  1283. the parser do the job for Ant:</p>
  1284. <pre class="code">
  1285. &lt;?xml version=&quot;1.0&quot;?&gt;
  1286. &lt;!DOCTYPE project [
  1287. &lt;!ENTITY common SYSTEM &quot;file:./common.xml&quot;&gt;
  1288. ]&gt;
  1289. &lt;project name=&quot;test&quot; default=&quot;test&quot; basedir=&quot;.&quot;&gt;
  1290. &lt;target name=&quot;setup&quot;&gt;
  1291. ...
  1292. &lt;/target&gt;
  1293. &amp;common;
  1294. ...
  1295. &lt;/project&gt;
  1296. </pre>
  1297. <p>will literally include the contents of <code>common.xml</code> where
  1298. you've placed the <code>&amp;common;</code> entity.</p>
  1299. <p>In combination with a DTD, this would look like this:</p>
  1300. <pre class="code">
  1301. &lt;!DOCTYPE project PUBLIC &quot;-//ANT//DTD project//EN&quot; &quot;file:./ant.dtd&quot; [
  1302. &lt;!ENTITY include SYSTEM &quot;file:./header.xml&quot;&gt;
  1303. ]&gt;
  1304. </pre>
  1305. <br>
  1306. <a name="mail-logger"></a>
  1307. <table border="0" cellspacing="0" cellpadding="2" width="100%">
  1308. <tr><td bgcolor="#4C6C8F">
  1309. <font color="#ffffff" face="arial,helvetica,sanserif">
  1310. <strong>
  1311. How do I send an email with the result of my build
  1312. process?
  1313. </strong>
  1314. </font>
  1315. </td></tr>
  1316. </table>
  1317. <p>If you are using a nightly build of Ant 1.5 after
  1318. 2001-12-14, you can use the built-in MailLogger:</p>
  1319. <pre class="code">
  1320. ant -logger org.apache.tools.ant.listener.MailLogger
  1321. </pre>
  1322. <p>See the <a href="http://cvs.apache.org/viewcvs/~checkout~/jakarta-ant/docs/manual/listeners.html?content-type=text/html">Listeners
  1323. &amp; Loggers</a> documentation for details on the properties
  1324. required.</p>
  1325. <p>For older versions of Ant, you can use a custom
  1326. BuildListener that sends out an email
  1327. in the buildFinished() method. Will Glozer
  1328. &lt;will.glozer@jda.com&gt; has written such a listener based
  1329. on <a href="http://java.sun.com/products/javamail/">JavaMail</a>.
  1330. The source is:</p>
  1331. <pre class="code">
  1332. import java.io.*;
  1333. import java.util.*;
  1334. import javax.mail.*;
  1335. import javax.mail.internet.*;
  1336. import org.apache.tools.ant.*;
  1337. /**
  1338. * A simple listener that waits for a build to finish and sends an email
  1339. * of the results. The settings are stored in &quot;monitor.properties&quot; and
  1340. * are fairly self explanatory.
  1341. *
  1342. * @author Will Glozer
  1343. * @version 1.05a 09/06/2000
  1344. */
  1345. public class BuildMonitor implements BuildListener {
  1346. protected Properties props;
  1347. /**
  1348. * Create a new BuildMonitor.
  1349. */
  1350. public BuildMonitor() throws Exception {
  1351. props = new Properties();
  1352. InputStream is = getClass().getResourceAsStream(&quot;monitor.properties&quot;);
  1353. props.load(is);
  1354. is.close();
  1355. }
  1356. public void buildStarted(BuildEvent e) {
  1357. }
  1358. /**
  1359. * Determine the status of the build and the actions to follow, now that
  1360. * the build has completed.
  1361. *
  1362. * @param e Event describing the build status.
  1363. */
  1364. public void buildFinished(BuildEvent e) {
  1365. Throwable th = e.getException();
  1366. String status = (th != null) ? &quot;failed&quot; : &quot;succeeded&quot;;
  1367. try {
  1368. String key = &quot;build.&quot; + status;
  1369. if (props.getProperty(key + &quot;.notify&quot;).equalsIgnoreCase(&quot;false&quot;)) {
  1370. return;
  1371. }
  1372. Session session = Session.getDefaultInstance(props, null);
  1373. MimeMessage message = new MimeMessage(session);
  1374. message.addRecipients(Message.RecipientType.TO, parseAddresses(
  1375. props.getProperty(key + &quot;.email.to&quot;)));
  1376. message.setSubject(props.getProperty(key + &quot;.email.subject&quot;));
  1377. BufferedReader br = new BufferedReader(new FileReader(
  1378. props.getProperty(&quot;build.log&quot;)));
  1379. StringWriter sw = new StringWriter();
  1380. String line = br.readLine();
  1381. while (line != null) {
  1382. sw.write(line);
  1383. sw.write(&quot;\n&quot;);
  1384. line = br.readLine();
  1385. }
  1386. br.close();
  1387. message.setText(sw.toString(), &quot;UTF-8&quot;);
  1388. sw.close();
  1389. Transport transport = session.getTransport();
  1390. transport.connect();
  1391. transport.send(message);
  1392. transport.close();
  1393. } catch (Exception ex) {
  1394. System.out.println(&quot;BuildMonitor failed to send email!&quot;);
  1395. ex.printStackTrace();
  1396. }
  1397. }
  1398. /**
  1399. * Parse a comma separated list of internet email addresses.
  1400. *
  1401. * @param s The list of addresses.
  1402. * @return Array of Addresses.
  1403. */
  1404. protected Address[] parseAddresses(String s) throws Exception {
  1405. StringTokenizer st = new StringTokenizer(s, &quot;,&quot;);
  1406. Address[] addrs = new Address[st.countTokens()];
  1407. for (int i = 0; i &lt; addrs.length; i++) {
  1408. addrs[i] = new InternetAddress(st.nextToken());
  1409. }
  1410. return addrs;
  1411. }
  1412. public void messageLogged(BuildEvent e) {
  1413. }
  1414. public void targetStarted(BuildEvent e) {
  1415. }
  1416. public void targetFinished(BuildEvent e) {
  1417. }
  1418. public void taskStarted(BuildEvent e) {
  1419. }
  1420. public void taskFinished(BuildEvent e) {
  1421. }
  1422. }
  1423. </pre>
  1424. <p>With a <code>monitor.properties</code> like this:</p>
  1425. <pre class="code">
  1426. # configuration for build monitor
  1427. mail.transport.protocol=smtp
  1428. mail.smtp.host=&lt;host&gt;
  1429. mail.from=Will Glozer &lt;will.glozer@jda.com&gt;
  1430. build.log=build.log
  1431. build.failed.notify=true
  1432. build.failed.email.to=will.glozer@jda.com
  1433. build.failed.email.subject=Nightly build failed!
  1434. build.succeeded.notify=true
  1435. build.succeeded.email.to=will.glozer@jda.com
  1436. build.succeeded.email.subject=Nightly build succeeded!
  1437. </pre>
  1438. <p><code>monitor.properties</code> should be placed right next
  1439. to your compiled <code>BuildMonitor.class</code>. To use it,
  1440. invoke Ant like:</p>
  1441. <pre class="code">
  1442. ant -listener BuildMonitor -logfile build.log
  1443. </pre>
  1444. <p>Make sure that <code>mail.jar</code> from JavaMail and
  1445. <code>activation.jar</code> from the
  1446. <a href="http://java.sun.com/products/javabeans/glasgow/jaf.html">Java
  1447. Beans Activation Framework</a> are in your <code>CLASSPATH</code>.</p>
  1448. <br>
  1449. <a name="listener-properties"></a>
  1450. <table border="0" cellspacing="0" cellpadding="2" width="100%">
  1451. <tr><td bgcolor="#4C6C8F">
  1452. <font color="#ffffff" face="arial,helvetica,sanserif">
  1453. <strong>
  1454. How do I get at the properties that Ant was running
  1455. with from inside BuildListener?
  1456. </strong>
  1457. </font>
  1458. </td></tr>
  1459. </table>
  1460. <p>You can get at a hashtable with all the properties that Ant
  1461. has been using through the BuildEvent parameter. For
  1462. example:</p>
  1463. <pre class="code">
  1464. public void buildFinished(BuildEvent e) {
  1465. Hashtable table = e.getProject().getProperties();
  1466. String buildpath = (String)table.get(&quot;build.path&quot;);
  1467. ...
  1468. }
  1469. </pre>
  1470. <p>This is more accurate than just reading the same property
  1471. files that your project does, since it will give the correct
  1472. results for properties that were specified on the Ant command line.</p>
  1473. <br>
  1474. <a name="remove-cr"></a>
  1475. <table border="0" cellspacing="0" cellpadding="2" width="100%">
  1476. <tr><td bgcolor="#4C6C8F">
  1477. <font color="#ffffff" face="arial,helvetica,sanserif">
  1478. <strong>
  1479. &lt;chmod&gt; or &lt;exec&gt; doesn't work in Ant
  1480. 1.3 on Unix
  1481. </strong>
  1482. </font>
  1483. </td></tr>
  1484. </table>
  1485. <p>The <code>antRun</code> script in <code>ANT_HOME/bin</code>
  1486. has DOS instead of Unix line endings; you must remove the
  1487. carriage-return characters from this file. This can be done by
  1488. using Ant's <code>&lt;fixcrlf&gt;</code> task
  1489. or something like:</p>
  1490. <pre class="code">
  1491. tr -d '\r' &lt; $ANT_HOME/bin/antRun &gt; /tmp/foo
  1492. mv /tmp/foo $ANT_HOME/bin/antRun
  1493. </pre>
  1494. <br>
  1495. <a name="javadoc-cannot-execute"></a>
  1496. <table border="0" cellspacing="0" cellpadding="2" width="100%">
  1497. <tr><td bgcolor="#4C6C8F">
  1498. <font color="#ffffff" face="arial,helvetica,sanserif">
  1499. <strong>
  1500. JavaDoc failed: java.io.IOException: javadoc: cannot execute
  1501. </strong>
  1502. </font>
  1503. </td></tr>
  1504. </table>
  1505. <p>There is a bug in the Solaris reference implementation of
  1506. the JDK (see <a href="http://developer.java.sun.com/developer/bugParade/bugs/4230399.html">http://developer.java.sun.com/developer/bugParade/bugs/4230399.html</a>).
  1507. This also appears to be true under Linux. Moving the JDK to
  1508. the front of the PATH fixes the problem.</p>
  1509. <br>
  1510. <a name="delegating-classloader"></a>
  1511. <table border="0" cellspacing="0" cellpadding="2" width="100%">
  1512. <tr><td bgcolor="#4C6C8F">
  1513. <font color="#ffffff" face="arial,helvetica,sanserif">
  1514. <strong>
  1515. &lt;style&gt; or &lt;junit&gt; ignores my
  1516. &lt;classpath&gt;
  1517. </strong>
  1518. </font>
  1519. </td></tr>
  1520. </table>
  1521. <p>These tasks don't ignore your classpath setting, you
  1522. are facing a common problem with delegating classloaders.</p>
  1523. <p>First of all let's state that Ant adds all
  1524. <code>.jar</code> files from <code>ANT_HOME/lib</code> to
  1525. <code>CLASSPATH</code>, therefore "in
  1526. <code>CLASSPATH</code>" shall mean "either in your
  1527. <code>CLASSPATH</code> environment variable or
  1528. <code>ANT_HOME/lib</code>" for the rest of this
  1529. answer.</p>
  1530. <p>This question collects a common type of problem: A task
  1531. needs an external library and it has a nested classpath
  1532. element so that you can point it to this external library, but
  1533. that doesn't work unless you put the external library into the
  1534. <code>CLASSPATH</code>.</p>
  1535. <p>The root of the problem is that the class that needs the
  1536. external library is on the <code>CLASSPATH</code>.</p>
  1537. <p>When you specify a nested <code>&lt;classpath&gt;</code> in
  1538. Ant, Ant creates a new class loader that uses the path you
  1539. have specified. It then tries to load additional classes from
  1540. this classloader.</p>
  1541. <p>In most cases - for example the two cases above - Ant
  1542. doesn't load the external library directly, it is the loaded
  1543. class that does so.</p>
  1544. <p>In the case of <code>&lt;junit&gt;</code> it is the task
  1545. implementation itself and in the case of
  1546. <code>&lt;style&gt;</code> it is the implementation of the
  1547. <code>org.apache.tools.ant.taskdefs.XSLTLiaison</code>
  1548. class.</p>
  1549. <p>Ant's class loader implementation uses Java's
  1550. delegation model, see <a href="http://java.sun.com/products/jdk/1.2/docs/api/java/lang/ClassLoader.html">http://java.sun.com/products/jdk/1.2/docs/api/java/lang/ClassLoader.html</a>
  1551. the paragraph</p>
  1552. <blockquote>The <code>ClassLoader</code> class uses a
  1553. delegation model to search for classes and resources. Each
  1554. instance of <code>ClassLoader</code> has an associated parent
  1555. class loader. When called upon to find a class or resource, a
  1556. <code>ClassLoader</code> instance will delegate the search for
  1557. the class or resource to its parent class loader before
  1558. attempting to find the class or resource itself. The virtual
  1559. machine's built-in class loader, called the bootstrap
  1560. class loader, does not itself have a parent but may serve as
  1561. the parent of a <code>ClassLoader</code>
  1562. instance.</blockquote>
  1563. <p>This means, Ant's class loader will consult the
  1564. bootstrap class loader first, which tries to load classes from
  1565. <code>CLASSPATH</code>. The bootstrap class loader
  1566. doesn't know anything about Ant's class loader or
  1567. even the path you have specified.</p>
  1568. <p>If the bootstrap class loader can load the class Ant has
  1569. asked it to load, this class will try to load the external
  1570. library from <code>CLASSPATH</code> as well - it doesn't
  1571. know anything else - and will not find it unless the library
  1572. is in <code>CLASSPATH</code> as well.</p>
  1573. <p>To solve this, you have two major options:</p>
  1574. <ol>
  1575. <li>put all external libraries you need in
  1576. <code>CLASSPATH</code> as well this is not what you want,
  1577. otherwise you wouldn't have found this FAQ entry.</li>
  1578. <li>remove the class that loads the external library from
  1579. the <code>CLASSPATH</code>.</li>
  1580. </ol>
  1581. <p>The easiest way to do this is to remove
  1582. <code>optional.jar</code> from <code>ANT_HOME/lib</code>. If
  1583. you do so, you will have to <code>&lt;taskdef&gt;</code> all
  1584. optional tasks and use nested <code>&lt;classpath&gt;</code>
  1585. elements in the <code>&lt;taskdef&gt;</code> tasks that point
  1586. to the new location of <code>optional.jar</code>. Also,
  1587. don't forget to add the new location of
  1588. <code>optional.jar</code> to the
  1589. <code>&lt;classpath&gt;</code> of your
  1590. <code>&lt;style&gt;</code> or <code>&lt;junit&gt;</code>
  1591. task.</p>
  1592. <p>If you want to avoid to <code>&lt;taskdef&gt;</code> all
  1593. optional tasks you need, the only other option is to remove
  1594. the classes that should not be loaded via the bootstrap class
  1595. loader from <code>optional.jar</code> and put them into a
  1596. separate archive. Add this separate archive to the
  1597. <code>&lt;classpath&gt;</code> of your
  1598. <code>&lt;style&gt;</code> or <code>&lt;junit&gt;</code> task
  1599. - and make sure the separate archive is not in
  1600. <code>CLASSPATH</code>.</p>
  1601. <p>In the case of <code>&lt;junit&gt;</code> you'd have
  1602. to remove all classes that are in the
  1603. <code>org/apache/tools/ant/taskdefs/optional/junit</code>
  1604. directory, in the <code>&lt;style&gt;</code> case it is one of
  1605. the <code>*Liaison</code> classes in
  1606. <code>org/apache/tools/ant/taskdefs/optional</code>.</p>
  1607. <p>If you use the option to break up <code>optional.jar</code>
  1608. for <code>&lt;junit&gt;</code>, you still have to use a
  1609. <code>&lt;taskdef&gt;</code> with a nested
  1610. <code>&lt;classpath&gt;</code> to define the junit task.</p>
  1611. <br>
  1612. <a name="winxp-jdk14-ant14"></a>
  1613. <table border="0" cellspacing="0" cellpadding="2" width="100%">
  1614. <tr><td bgcolor="#4C6C8F">
  1615. <font color="#ffffff" face="arial,helvetica,sanserif">
  1616. <strong>
  1617. When running Ant 1.4 on Windows XP and JDK 1.4, I get
  1618. various errors when trying to <code>&lt;exec&gt;</code>, fork
  1619. <code>&lt;java&gt;</code> or access environment
  1620. variables.
  1621. </strong>
  1622. </font>
  1623. </td></tr>
  1624. </table>
  1625. <p>Ant &lt; 1.5 doesn't recognize Windows XP as a flavor
  1626. of Windows that runs <code>CMD.EXE</code> instead of
  1627. <code>COMMAND.COM</code>. JDK 1.3 will tell Ant that Windows
  1628. XP is Windows 2000 so the problem doesn't show up
  1629. there.</p>
  1630. <p>Apart from upgrading to Ant 1.5 or better, setting the
  1631. environment variable <code>ANT_OPTS</code> to
  1632. <code>-Dos.name=Windows_NT</code> prior to invoking Ant has
  1633. been confirmed as a workaround.</p>
  1634. <br>
  1635. <a name="1.5-cygwin-sh"></a>
  1636. <table border="0" cellspacing="0" cellpadding="2" width="100%">
  1637. <tr><td bgcolor="#4C6C8F">
  1638. <font color="#ffffff" face="arial,helvetica,sanserif">
  1639. <strong>
  1640. The <code>ant</code> wrapper script of Ant 1.5 fails
  1641. for Cygwin if <code>ANT_HOME</code> is set to a Windows style
  1642. path.
  1643. </strong>
  1644. </font>
  1645. </td></tr>
  1646. </table>
  1647. <p>This problem has been reported only hours after Ant 1.5 has
  1648. been released, see <a href="http://nagoya.apache.org/bugzilla/show_bug.cgi?id=10664">Bug
  1649. 10664</a> and all it's duplicates.</p>
  1650. <p>A fixed version of the wrapper script can be found <a href="http://jakarta.apache.org/builds/jakarta-ant/release/v1.5/errata/">here</a>.
  1651. Simply replace your script with this version.</p>
  1652. <br>
  1653. </div>
  1654. </td><td width="10"><img width="10" height="1" alt="" src="images/spacer.gif"></td>
  1655. </tr>
  1656. </table>
  1657. </td>
  1658. </tr>
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  1663. </tr>
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  1665. <td colspan="2" bgcolor="#CFDCED" class="copyright" align="center"><font size="2" face="Arial, Helvetica, Sans-Serif">Copyright &copy;
  1666. 2000-2003&nbsp;The Apache Software Foundation. All rights reserved.<script type="text/javascript" language="JavaScript"><!--
  1667. document.write(" - "+"Last Published: " + document.lastModified);
  1668. // --></script></font></td>
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