mirror of
https://github.com/apache/ant.git
synced 2025-05-18 14:04:48 +00:00
8facf5e78b
Obtained from: Larry Shatzer git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@278015 13f79535-47bb-0310-9956-ffa450edef68
985 lines
43 KiB
HTML
985 lines
43 KiB
HTML
<html>
|
||
<head>
|
||
<link rel="stylesheet" type="text/css" href="stylesheets/style.css"/>
|
||
<title>Tutorial: Tasks using Properties, Filesets & Paths</title>
|
||
<meta name="author" content="Jan Matèrne">
|
||
<style type="text/css">
|
||
<!--
|
||
.code { background: #EFEFEF; margin-top: }
|
||
.output { color: #FFFFFF; background: #837A67; }
|
||
-->
|
||
</style>
|
||
</head>
|
||
<body>
|
||
<h1>Tutorial: Tasks using Properties, Filesets & Paths</h1>
|
||
|
||
<p>After reading the tutorial about <a href="tutorial-writing-tasks.html">writing
|
||
tasks [1]</a> this tutorial explains how to get and set properties and how to use
|
||
nested filesets and paths. Finally it explains how to contribute tasks to Ant.</p>
|
||
|
||
<h2>Content</h2>
|
||
<p><ul>
|
||
<li><a href="#goal">The goal</a></li>
|
||
<li><a href="#buildenvironment">Build environment</a></li>
|
||
<li><a href="#propertyaccess">Property access</a></li>
|
||
<li><a href="#filesets">Using filesets</a></li>
|
||
<li><a href="#path">Using nested paths</a></li>
|
||
<li><a href="#returning-list">Returning a list</a></li>
|
||
<li><a href="#documentation">Documentation</a></li>
|
||
<li><a href="#contribute">Contribute the new task</a></li>
|
||
<li><a href="#resources">Resources</a></li>
|
||
</ul></p>
|
||
|
||
|
||
<a name="goal"/>
|
||
<h2>The goal</h2>
|
||
<p>The goal is to write a task, which searchs in a path for a file and saves the
|
||
location of that file in a property.</p>
|
||
|
||
|
||
<a name="buildenvironment"/>
|
||
<h2>Build environment</h2>
|
||
<p>We can use the buildfile from the other tutorial and modify it a little bit.
|
||
That's the advantage of using properties - we can reuse nearly the whole script. :-)</p>
|
||
<pre class="code">
|
||
<?xml version="1.0" encoding="ISO-8859-1"?>
|
||
<project name="<b>FindTask</b>" basedir="." default="test">
|
||
...
|
||
<target name="use.init" description="Taskdef's the <b>Find</b>-Task" depends="jar">
|
||
<taskdef name="<b>find</b>" classname="<b>Find</b>" classpath="${ant.project.name}.jar"/>
|
||
</target>
|
||
|
||
<b><!-- the other use.* targets are deleted --></b>
|
||
...
|
||
</project>
|
||
</pre>
|
||
|
||
<p>The buildfile is in the archive <a href="tutorial-tasks-filesets-properties.zip">
|
||
tutorial-tasks-filesets-properties.zip [2]</a> in <tt>/build.xml.01-propertyaccess</tt>
|
||
(future version saved as *.02..., final version as build.xml; same for sources).</p>
|
||
|
||
|
||
<a name="propertyaccess"/>
|
||
<h2>Property access</h2>
|
||
<p>Our first step is to set a property to a value and print the value of that property.
|
||
So our scenario would be
|
||
<pre class="code">
|
||
<find property="test" value="test-value"/>
|
||
<find print="test"/>
|
||
</pre>
|
||
ok, can be rewritten with the core tasks
|
||
<pre class="code">
|
||
<property name="test" value="test-value"/>
|
||
<echo message="${test}"/>
|
||
</pre>
|
||
but I have to start on known ground :-)</p>
|
||
<p>So what to do? Handling three attributes (property, value, print) and an execute method.
|
||
Because this is only an introduction example I don't do much checking:
|
||
|
||
<pre class="code">
|
||
import org.apache.tools.ant.BuildException;
|
||
|
||
public class Find extends Task {
|
||
|
||
private String property;
|
||
private String value;
|
||
private String print;
|
||
|
||
public void setProperty(String property) {
|
||
this.property = property;
|
||
}
|
||
|
||
// setter for value and print
|
||
|
||
public void execute() {
|
||
if (print != null) {
|
||
String propValue = <b>getProject().getProperty(print)</b>;
|
||
log(propValue);
|
||
} else {
|
||
if (property == null) throw new BuildException("property not set");
|
||
if (value == null) throw new BuildException("value not set");
|
||
<b>getProject().setNewProperty(property, value)</b>;
|
||
}
|
||
}
|
||
}
|
||
</pre>
|
||
|
||
As said in the other tutorial, the property access is done via Project instance.
|
||
We get this instance via the public <tt>getProject()</tt> method which we inherit from
|
||
<tt>Task</tt> (more precise from ProjectComponent). Reading a property is done via
|
||
<tt>getProperty(<i>propertyname</i>)</tt> (very simple, isn't it?). This property returns
|
||
the value as String or <i>null</i> if not set.<br>
|
||
Setting a property is ... not really difficult, but there is more than one setter. You can
|
||
use the <tt>setProperty()</tt> method which will do the job like expected. But there is
|
||
a golden rule in Ant: <i>properties are immutable</i>. And this method sets the property
|
||
to the specified value - whether it has a value before that or not. So we use another
|
||
way. <tt>setNewProperty()</tt> sets the property only if there is no property with that
|
||
name. Otherwise a message is logged.</p>
|
||
|
||
<p><i>(by the way: a short word to ants "namespaces" (don't
|
||
be confused with xml namespaces:
|
||
an <code><antcall></code> creates a new space for property names. All properties from the caller
|
||
are passed to the callee, but the callee can set its own properties without notice by the
|
||
caller.)</i></p>
|
||
|
||
<p>There are some other setter, too (but I haven't used them, so I can't say something
|
||
to them, sorry :-)</p>
|
||
|
||
<p>After putting our two line example from above into a target names <tt>use.simple</tt>
|
||
we can call that from our testcase:
|
||
|
||
<pre class="code">
|
||
import org.apache.tools.ant.BuildFileTest;
|
||
|
||
public class FindTest extends BuildFileTest {
|
||
|
||
public FindTest(String name) {
|
||
super(name);
|
||
}
|
||
|
||
public void setUp() {
|
||
configureProject("build.xml");
|
||
}
|
||
|
||
public void testSimple() {
|
||
<b>expectLog("use.simple", "test-value");</b>
|
||
}
|
||
}
|
||
</pre>
|
||
|
||
and all works fine.</p>
|
||
|
||
|
||
|
||
<a name="filesets"/>
|
||
<h2>Using filesets</h2>
|
||
<p>Ant provides a common way of bundling files: the fileset. Because you are reading
|
||
this tutorial I think you know them and I don't have to spend more explanations about
|
||
their usage in buildfiles. Our goal is to search a file in path. And on this step the
|
||
path is simply a fileset (or more precise: a collection of filesets). So our usage
|
||
would be
|
||
<pre class="code">
|
||
<find file="ant.jar" location="location.ant-jar">
|
||
<fileset dir="${ant.home}" includes="**/*.jar"/>
|
||
</find>
|
||
</pre>
|
||
</p>
|
||
|
||
<p>What do we need? A task with two attributes (file, location) and nested
|
||
filesets. Because we had attribute handling already explained in the example above and the
|
||
handling of nested elements is described in the other tutorial the code should be very easy:
|
||
<pre class="code">
|
||
public class Find extends Task {
|
||
|
||
private String file;
|
||
private String location;
|
||
private Vector filesets = new Vector();
|
||
|
||
public void setFile(String file) {
|
||
this.file = file;
|
||
}
|
||
|
||
public void setLocation(String location) {
|
||
this.location = location;
|
||
}
|
||
|
||
public void addFileset(FileSet fileset) {
|
||
filesets.add(fileset);
|
||
}
|
||
|
||
public void execute() {
|
||
}
|
||
}
|
||
</pre>
|
||
Ok - that task wouldn't do very much, but we can use it in the described manner without
|
||
failure. On next step we have to implement the execute method. And before that we will
|
||
implement the appropriate testcases (TDD - test driven development).</p>
|
||
|
||
<p>In the other tutorial we have reused the already written targets of our buildfile.
|
||
Now we will configure most of the testcases via java code (sometimes it's much easier
|
||
to write a target than doing it via java coding). What can be tested?<ul>
|
||
<li>not valid configured task (missing file, missing location, missing fileset)</li>
|
||
<li>don't find a present file</li>
|
||
<li>behaviour if file can't be found</li>
|
||
</ul>
|
||
Maybe you find some more testcases. But this is enough for now.<br>
|
||
For each of these points we create a <tt>testXX</tt> method.</p>
|
||
|
||
<pre class="code">
|
||
public class FindTest extends BuildFileTest {
|
||
|
||
... // constructor, setUp as above
|
||
|
||
public void testMissingFile() {
|
||
<b>Find find = new Find();</b>
|
||
try {
|
||
<b>find.execute();</b>
|
||
fail("No 'no-file'-exception thrown.");
|
||
} catch (Exception e) {
|
||
// exception expected
|
||
String expected = "file not set";
|
||
assertEquals("Wrong exception message.", expected, e.getMessage());
|
||
}
|
||
}
|
||
|
||
public void testMissingLocation() {
|
||
Find find = new Find();
|
||
<b>find.setFile("ant.jar");</b>
|
||
try {
|
||
find.execute();
|
||
fail("No 'no-location'-exception thrown.");
|
||
} catch (Exception e) {
|
||
... // similar to testMissingFile()
|
||
}
|
||
}
|
||
|
||
public void testMissingFileset() {
|
||
Find find = new Find();
|
||
find.setFile("ant.jar");
|
||
find.setLocation("location.ant-jar");
|
||
try {
|
||
find.execute();
|
||
fail("No 'no-fileset'-exception thrown.");
|
||
} catch (Exception e) {
|
||
... // similar to testMissingFile()
|
||
}
|
||
}
|
||
|
||
public void testFileNotPresent() {
|
||
executeTarget("testFileNotPresent");
|
||
String result = getProject().getProperty("location.ant-jar");
|
||
assertNull("Property set to wrong value.", result);
|
||
}
|
||
|
||
public void testFilePresent() {
|
||
executeTarget("testFilePresent");
|
||
String result = getProject().getProperty("location.ant-jar");
|
||
assertNotNull("Property not set.", result);
|
||
assertTrue("Wrong file found.", result.endsWith("ant.jar"));
|
||
}
|
||
}
|
||
</pre>
|
||
|
||
<p>If we run this test class all test cases (except <i>testFileNotPresent</i>) fail. No we
|
||
can implement our task, so that these test cases will pass.</p>
|
||
|
||
<pre class="code">
|
||
protected void validate() {
|
||
if (file==null) throw new BuildException("file not set");
|
||
if (location==null) throw new BuildException("location not set");
|
||
if (filesets.size()<1) throw new BuildException("fileset not set");
|
||
}
|
||
|
||
public void execute() {
|
||
validate(); // 1
|
||
String foundLocation = null;
|
||
for(Iterator itFSets = filesets.iterator(); itFSets.hasNext(); ) { // 2
|
||
FileSet fs = (FileSet)itFSets.next();
|
||
DirectoryScanner ds = fs.getDirectoryScanner(getProject()); // 3
|
||
String[] includedFiles = ds.getIncludedFiles();
|
||
for(int i=0; i<includedFiles.length; i++) {
|
||
String filename = includedFiles[i].replace('\\','/'); // 4
|
||
filename = filename.substring(filename.lastIndexOf("/")+1);
|
||
if (foundLocation==null && file.equals(filename)) {
|
||
File base = ds.getBasedir(); // 5
|
||
File found = new File(base, includedFiles[i]);
|
||
foundLocation = found.getAbsolutePath();
|
||
}
|
||
}
|
||
}
|
||
if (foundLocation!=null) // 6
|
||
getProject().setNewProperty(location, foundLocation);
|
||
}
|
||
</pre>
|
||
|
||
<p>On <b>//1</b> we check the prerequisites for our task. Doing that in a <tt>validate</tt>-method
|
||
is a common way, because we separate the prerequisites from the real work. On <b>//2</b> we iterate
|
||
over all nested filesets. If we don't want to handle multiple filesets, the <tt>addFileset()</tt>
|
||
method has to reject the further calls. We can get the result of a fileset via its DirectoryScanner
|
||
like done in <b>//3</b>. After that we create a plattform independend String representation of
|
||
the file path (<b>//4</b>, can be done in other ways of course). We have to do the <tt>replace()</tt>,
|
||
because we work with a simple string comparison. Ant itself is platform independant and can
|
||
therefore run on filesystems with slash (/, e.g. Linux) or backslash (\, e.g. Windows) as
|
||
path separator. Therefore we have to unify that. If we found our file we create an absolute
|
||
path representation on <b>//5</b>, so that we can use that information without knowing the basedir.
|
||
(This is very important on use with multiple filesets, because they can have different basedirs
|
||
and the return value of the directory scanner is relative to its basedir.) Finally we store the
|
||
location of the file as property, if we had found one (<b>//6</b>).</p>
|
||
|
||
<p>Ok, much more easier in this simple case would be to add the <i>file</i> as additional
|
||
<i>include</i> element to all filesets. But I wanted to show how to handle complex situations
|
||
whithout being complex :-)</p>
|
||
|
||
<p>The test case uses the ant property <i>ant.home</i> as reference. This property is set by the
|
||
<tt>Launcher</tt> class which starts ant. We can use that property in our buildfiles as a
|
||
<a href="using.html#built-in-props">build-in property [3]</a>. But if we create a new ant
|
||
environment we have to set that value for our own. And we use the <code><junit></code> task in fork-mode.
|
||
Therefore we have do modify our buildfile:
|
||
<pre class="code">
|
||
<target name="junit" description="Runs the unit tests" depends="jar">
|
||
<delete dir="${junit.out.dir.xml}"/>
|
||
<mkdir dir="${junit.out.dir.xml}"/>
|
||
<junit printsummary="yes" haltonfailure="no">
|
||
<classpath refid="classpath.test"/>
|
||
<b><sysproperty key="ant.home" value="${ant.home}"/></b>
|
||
<formatter type="xml"/>
|
||
<batchtest fork="yes" todir="${junit.out.dir.xml}">
|
||
<fileset dir="${src.dir}" includes="**/*Test.java"/>
|
||
</batchtest>
|
||
</junit>
|
||
</target>
|
||
</pre>
|
||
|
||
|
||
<a name="path"/>
|
||
<h2>Using nested paths</h2>
|
||
<p>A task providing support for filesets is a very comfortable one. But there is another
|
||
possibility of bundling files: the <code><path></code>. Fileset are easy if the files are all under
|
||
a common base directory. But if this is not the case you have a problem. Another disadvantage
|
||
is its speed: if you have only a few files in a huge directory structure, why not use a
|
||
<code><filelist></code> instead? <code><path></code>s combines these datatypes in that way that a path contains
|
||
other paths, filesets, dirsets and filelists. This is why <a href="http://ant-contrib.sourceforge.net/">
|
||
Ant-Contribs [4]</a> <code><foreach></code> task is modified to support paths instead of filesets. So we want that,
|
||
too.</p>
|
||
|
||
<p>Changing from fileset to path support is very easy:</p>
|
||
<pre class="code">
|
||
<i><b>Change java code from:</b></i>
|
||
private Vector filesets = new Vector();
|
||
public void addFileset(FileSet fileset) {
|
||
filesets.add(fileset);
|
||
}
|
||
<i><b>to:</b></i>
|
||
private Vector paths = new Vector(); *1
|
||
public void add<b>Path</b>(<b>Path</b> path) { *2
|
||
paths.add(path);
|
||
}
|
||
<i><b>and build file from:</b></i>
|
||
<find file="ant.jar" location="location.ant-jar">
|
||
<fileset dir="${ant.home}" includes="**/*.jar"/>
|
||
</find>
|
||
<i><b>to:</b></i>
|
||
<find file="ant.jar" location="location.ant-jar">
|
||
<b><path></b> *3
|
||
<fileset dir="${ant.home}" includes="**/*.jar"/>
|
||
</path>
|
||
</find>
|
||
</pre>
|
||
<p>On <b>*1</b> we rename only the vector. It<49>s just for better reading the source. On <b>*2</b>
|
||
we have to provide the right method: an add<i>Name</i>(<i>Type</i> t). Therefore replace the
|
||
fileset with path here. Finally we have to modify our buildfile on <b>*3</b> because our task
|
||
doesn<EFBFBD>t support nested filesets any longer. So we wrap the fileset inside a path.</p>
|
||
|
||
<p>And now we modify the testcase. Oh, not very much to do :-) Renaming the <tt>testMissingFileset()</tt>
|
||
(not really a <i>must-be</i> but better it<69>s named like the think it does) and update the
|
||
<i>expected</i>-String in that method (now a <tt>path not set</tt> message is expected). The more complex
|
||
test cases base on the buildscript. So the targets <tt>testFileNotPresent</tt> and <tt>testFilePresent</tt> have to be
|
||
modified in the manner described above.</p>
|
||
|
||
<p>The test are finished. Now we have to adapt the task implementation. The easiest modification is
|
||
in the <tt>validate()</tt> method where we change le last line to <tt>if (paths.size()<1) throw new
|
||
BuildException("path not set");</tt>. In the <tt>execute()</tt> method we have a little more work.
|
||
... mmmh ... in reality it's lesser work, because the Path class does the whole DirectoryScanner-handling
|
||
and creating-absolute-paths stuff for us. So the execute method is just:</p>
|
||
|
||
<pre class="code">
|
||
public void execute() {
|
||
validate();
|
||
String foundLocation = null;
|
||
for(Iterator itPaths = paths.iterator(); itPaths.hasNext(); ) {
|
||
Path path = (<b>Path</b>)itPaths.next(); // 1
|
||
String[] includedFiles = <b>path.list()</b>; // 2
|
||
for(int i=0; i<includedFiles.length; i++) {
|
||
String filename = includedFiles[i].replace('\\','/');
|
||
filename = filename.substring(filename.lastIndexOf("/")+1);
|
||
if (foundLocation==null && file.equals(filename)) {
|
||
<b>foundLocation = includedFiles[i];</b> // 3
|
||
}
|
||
}
|
||
}
|
||
if (foundLocation!=null)
|
||
getProject().setNewProperty(location, foundLocation);
|
||
}
|
||
</pre>
|
||
|
||
<p>Of course we have to do the typecase to Path on <b>//1</b>. On <b>//2</b> and <b>//3</b>
|
||
we see that the Path class does the work for us: no DirectoryScanner (was at 2) and no
|
||
creating of the absolute path (was at 3).</p>
|
||
|
||
|
||
|
||
<a name="returning-list"/>
|
||
<h2>Returning a list</h2>
|
||
<p>So far so good. But could a file be on more than one place in the path? - Of course.<br>
|
||
And would it be good to get all of them? - It depends on ...<p>
|
||
|
||
<p>In this section we will extend that task to support returning a list of all files.
|
||
Lists as property values are not supported by Ant natively. So we have to see how other
|
||
tasks use lists. The most famous task using lists is Ant-Contribs <code><foreach></code>. All list
|
||
elements are concatenated and separated with a customizable separator (default ',').</p>
|
||
|
||
<p>So we do the following:</p>
|
||
|
||
<pre class="code">
|
||
<find ... <b>delimiter=""</b>/> ... </find>
|
||
</pre>
|
||
|
||
<p>If the delimiter is set we will return all found files as list with that delimiter.</p>
|
||
|
||
<p>Therefore we have to<ul>
|
||
<li>provide a new attribute</li>
|
||
<li>collect more than the first file</li>
|
||
<li>delete duplicates</li>
|
||
<li>create the list if necessary</li>
|
||
<li>return that list</li>
|
||
</ul></p>
|
||
|
||
<p>So we add as testcase:</p>
|
||
<pre class="code">
|
||
<b><i>in the buildfile:</i></b>
|
||
<target name="test.init">
|
||
<mkdir dir="test1/dir11/dir111"/> *1
|
||
<mkdir dir="test1/dir11/dir112"/>
|
||
...
|
||
<touch file="test1/dir11/dir111/test"/>
|
||
<touch file="test1/dir11/dir111/not"/>
|
||
...
|
||
<touch file="test1/dir13/dir131/not2"/>
|
||
<touch file="test1/dir13/dir132/test"/>
|
||
<touch file="test1/dir13/dir132/not"/>
|
||
<touch file="test1/dir13/dir132/not2"/>
|
||
<mkdir dir="test2"/>
|
||
<copy todir="test2"> *2
|
||
<fileset dir="test1"/>
|
||
</copy>
|
||
</target>
|
||
|
||
<target name="testMultipleFiles" depends="use.init,<b>test.init</b>"> *3
|
||
<find file="test" location="location.test" <b>delimiter=";"</b>>
|
||
<path>
|
||
<fileset dir="test1"/>
|
||
<fileset dir="test2"/>
|
||
</path>
|
||
</find>
|
||
<delete> *4
|
||
<fileset dir="test1"/>
|
||
<fileset dir="test2"/>
|
||
</delete>
|
||
</target>
|
||
|
||
<b><i>in the test class:</i></b>
|
||
public void testMultipleFiles() {
|
||
executeTarget("testMultipleFiles");
|
||
String result = getProject().getProperty("location.test");
|
||
assertNotNull("Property not set.", result);
|
||
assertTrue("Only one file found.", result.indexOf(";") > -1);
|
||
}
|
||
</pre>
|
||
|
||
<p>Now we need a directory structure where we CAN find files with the same
|
||
name in different directories. Because we can't sure to have one we create
|
||
one on <b>*1</b> and <b>*2</b>. And of course we clean up that on <b>*4</b>. The creation
|
||
can be done inside our test target or in a separate one, which will be better
|
||
for reuse later (<b>*3</b>).
|
||
|
||
<p>The task implementation is modified as followed:</p>
|
||
|
||
<pre class="code">
|
||
private Vector foundFiles = new Vector();
|
||
...
|
||
private String delimiter = null;
|
||
...
|
||
public void setDelimiter(String delim) {
|
||
delimiter = delim;
|
||
}
|
||
...
|
||
public void execute() {
|
||
validate();
|
||
// find all files
|
||
for(Iterator itPaths = paths.iterator(); itPaths.hasNext(); ) {
|
||
Path path = (Path)itPaths.next();
|
||
String[] includedFiles = path.list();
|
||
for(int i=0; i<includedFiles.length; i++) {
|
||
String filename = includedFiles[i].replace('\\','/');
|
||
filename = filename.substring(filename.lastIndexOf("/")+1);
|
||
if (file.equals(filename) && <b>!foundFiles.contains(includedFiles[i]</b>)) { // 1
|
||
foundFiles.add(includedFiles[i]);
|
||
}
|
||
}
|
||
}
|
||
|
||
// create the return value (list/single)
|
||
String rv = null;
|
||
if (foundFiles.size() > 0) { // 2
|
||
if (delimiter==null) {
|
||
// only the first
|
||
rv = (String)foundFiles.elementAt(0);
|
||
} else {
|
||
// create list
|
||
StringBuffer list = new StringBuffer();
|
||
for(Iterator it=foundFiles.iterator(); it.hasNext(); ) { // 3
|
||
list.append(it.next());
|
||
if (<b>it.hasNext()</b>) list.append(delimiter); // 4
|
||
}
|
||
rv = list.toString();
|
||
}
|
||
}
|
||
|
||
// create the property
|
||
if (rv!=null)
|
||
getProject().setNewProperty(location, rv);
|
||
}
|
||
</pre>
|
||
|
||
<p>The algorithm does: finding all files, creating the return value depending on the users
|
||
wish, returning the value as property. On <b>//1</b> we eliminates the duplicates. <b>//2</b>
|
||
ensures that we create the return value only if we have found one file. On <b>//3</b> we
|
||
iterate over all found files and <b>//4</b> ensures that the last entry has no trailing
|
||
delimiter.</p>
|
||
|
||
<p>Ok, first searching for all files and then returning only the first one ... You can
|
||
tune the performance of your own :-)</p>
|
||
|
||
|
||
<a name="documentation"/>
|
||
<h2>Documentation</h2>
|
||
<p>A task is useless if the only who is able to code the buildfile is the task developer
|
||
(and he only the next few weeks :-). So documentation is also very important. In which
|
||
form you do that depends on your favourite. But inside Ant there is a common format and
|
||
it has advantages if you use that: all task users know that form, this form is requested if
|
||
you decide to contribute your task. So we will doc our task in that form.</p>
|
||
|
||
<p>If you have a look at the manual page of the <a href="CoreTasks/java.html">java [5]</a>
|
||
task you will see<ul>
|
||
<li>it is plain html</li>
|
||
<li>starts with the name</li>
|
||
<li>has sections: description, parameters, nested elements, (maybe return codes) and (most
|
||
important :-) examples</li>
|
||
<li>parameters are listed in a table with columns for attribute name, its description and whether
|
||
it's required (if you add a feature after an Ant release, provide a <tt>since Ant xx</tt>
|
||
statement when it's introduced)</li>
|
||
<li>describe the nested elements (since-statement if necessary)</li>
|
||
<li>provide one or more useful examples; first code then description</li>
|
||
</ul>
|
||
As a template we have:
|
||
|
||
<pre class="code">
|
||
<html>
|
||
|
||
<head>
|
||
<meta http-equiv="Content-Language" content="en-us">
|
||
<title> <b>Taskname</b> Task</title>
|
||
</head>
|
||
|
||
<body>
|
||
|
||
<h2><a name="<i>taskname</i>"><b>Taskname</b></a></h2>
|
||
<h3>Description</h3>
|
||
<p> <b>Describe the task.</b></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>
|
||
|
||
<b>do this html row for each attribute (including inherited attributes)</b>
|
||
<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>
|
||
|
||
</table>
|
||
|
||
<h3>Parameters specified as nested elements</h3>
|
||
|
||
<b>Describe each nested element (including inherited)</b>
|
||
<h4>your nested element</b></h4>
|
||
<p> <b>description</b> </p>
|
||
<p><em>since Ant 1.6</em>.</p>
|
||
|
||
<h3>Examples</h3>
|
||
<pre>
|
||
<b>A code sample; don't forget to escape the < of the tags with &lt;</b>
|
||
</pre>
|
||
<b>what should that example do?</b>
|
||
|
||
</body>
|
||
</html>
|
||
</pre>
|
||
|
||
<p>For our task we have <a href="CoreTasks/find.html">that [6]</a>:</p>
|
||
<pre class="code">
|
||
<html>
|
||
|
||
<head>
|
||
<meta http-equiv="Content-Language" content="en-us">
|
||
<title> Find Task</title>
|
||
</head>
|
||
|
||
<body>
|
||
|
||
<h2><a name="find">Find</a></h2>
|
||
<h3>Description</h3>
|
||
<p>Searchs in a given path for a file and returns the absolute to it as property.
|
||
If delimiter is set this task returns all found locations.</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">file</td>
|
||
<td valign="top">The name of the file to search.</td>
|
||
<td align="center" valign="top">yes</td>
|
||
</tr>
|
||
<tr>
|
||
<td valign="top">location</td>
|
||
<td valign="top">The name of the property where to store the location</td>
|
||
<td align="center" valign="top">yes</td>
|
||
</tr>
|
||
<tr>
|
||
<td valign="top">delimiter</td>
|
||
<td valign="top">A delimiter to use when returning the list</td>
|
||
<td align="center" valign="top">only if the list is required</td>
|
||
</tr>
|
||
</table>
|
||
|
||
<h3>Parameters specified as nested elements</h3>
|
||
|
||
<h4>path</h4>
|
||
<p>The path where to search the file.</p>
|
||
|
||
<h3>Examples</h3>
|
||
<pre>
|
||
<find file="ant.jar" location="loc">
|
||
<path>
|
||
<fileset dir="${ant.home}"/>
|
||
<path>
|
||
</find>
|
||
</pre>
|
||
Searches in Ants home directory for a file <i>ant.jar</i> and stores its location in
|
||
property <i>loc</i> (should be ANT_HOME/bin/ant.jar).
|
||
|
||
<pre>
|
||
<find file="ant.jar" location="loc" delimiter=";">
|
||
<path>
|
||
<fileset dir="C:/"/>
|
||
<path>
|
||
</find>
|
||
<echo>ant.jar found in: ${loc}</echo>
|
||
</pre>
|
||
Searches in Windows C: drive for all <i>ant.jar</i> and stores their locations in
|
||
property <i>loc</i> delimited with <i>';'</i>. (should need a long time :-)
|
||
After that it prints out the result (e.g. C:/ant-1.5.4/bin/ant.jar;C:/ant-1.6/bin/ant.jar).
|
||
|
||
</body>
|
||
</html>
|
||
</pre>
|
||
|
||
|
||
<a name="contribute"/>
|
||
<h2>Contribute the new task</h2>
|
||
If we decide to contribute our task, we should do some things:<ul>
|
||
<li>is our task welcome? :-) Simply ask on the user list</li>
|
||
<li>is the right package used? </li>
|
||
<li>is the code conform to the styleguide?</li>
|
||
<li>do all tests pass? </li>
|
||
<li>does the code compile on JDK 1.2 (and passes all tests there)?</li>
|
||
<li>code under Apache license</li>
|
||
<li>create a patch file</li>
|
||
<li>publishing that patch file</li>
|
||
</ul>
|
||
The <a href="../ant_task_guidelines.html">Ant Task Guidelines [7]</a> support additional
|
||
information on that.</p>
|
||
|
||
<p>Now we will check the "Checklist before submitting a new task" described in that guideline.
|
||
<ul>
|
||
<li>Java file begins with Apache copyright and license statement. <b><i>must do that</i></b></li>
|
||
<li>Task does not depend on GPL or LGPL code. <b><i>ok</i></b></li>
|
||
<li>Source code complies with style guidelines <b><i>have to check (checkstyle)</i></b></li>
|
||
<li>Code compiles and runs on Java1.2 <b><i>have to try</i></b></li>
|
||
<li>Member variables are private, and provide public accessor methods
|
||
if access is actually needed. <b><i>have to check (checkstyle)</i></b></li>
|
||
<li><i>Maybe</i> Task has failonerror attribute to control failure behaviour <b><i>hasn't</i></b></li>
|
||
<li>New test cases written and succeed <b><i>passed on JDK 1.4, have to try on JDK 1.2</i></b></li>
|
||
<li>Documentation page written <b><i>ok</i></b></li>
|
||
<li>Example task declarations in the documentation tested. <b><i>ok (used in tests)</i></b></li>
|
||
<li>Patch files generated using cvs diff -u <b><i>to do</i></b></li>
|
||
<li>patch files include a patch to defaults.properties to register the
|
||
tasks <b><i>to do</i></b></li>
|
||
<li>patch files include a patch to coretasklist.html or
|
||
optionaltasklist.html to link to the new task page <b><i>to do</i></b></li>
|
||
<li>Message to dev contains [SUBMIT] and task name in subject <b><i>to do</i></b></li>
|
||
<li>Message body contains a rationale for the task <b><i>to do</i></b></li>
|
||
<li>Message attachments contain the required files -source, documentation,
|
||
test and patches zipped up to escape the HTML filter. <b><i>to do</i></b></li>
|
||
</ul>
|
||
|
||
|
||
<h3>Package / Directories</h3>
|
||
<p>This task does not depend on any external library. Therefore we can use this as
|
||
a core task. This task contains only one class. So we can use the standard package
|
||
for core tasks: <tt>org.apache.tools.ant.taskdefs</tt>. Implementations are in the
|
||
directory <tt>src/main</tt>, tests in <tt>src/testcases</tt> and buildfiles for
|
||
tests in <tt>src/etc/testcases</tt>.</p>
|
||
|
||
<p>Now we integrate our work into Ants distribution. So first we do an update of our
|
||
cvs tree. If not done yet, you have to checkout the ant module from Apaches cvs server
|
||
as described in <a href="http://ant.apache.org/cvs.html">Access the Source Tree (AnonCVS)
|
||
[8]</a> (password is <i>anoncvs</i>):<pre class="output">
|
||
cvs -d :pserver:anoncvs@cvs.apache.org:/home/cvspublic login //1
|
||
cvs -d :pserver:anoncvs@cvs.apache.org:/home/cvspublic checkout ant //2
|
||
</pre>
|
||
If you have a local copy of Ants sources just do an update
|
||
<pre class="output">
|
||
cvs -d :pserver:anoncvs@cvs.apache.org:/home/cvspublic login
|
||
cd ant //3
|
||
cvs -d :pserver:anoncvs@cvs.apache.org:/home/cvspublic update //4
|
||
</pre></p>
|
||
|
||
<p>We use the <i>-d</i> flag on <b>//1</b> to specifiy the cvs directory. You can
|
||
specify the environment variable CVSROOT with that value and after that you haven<65>t
|
||
to use that flag any more. On <b>//2</b> we get the whole cvs tree of ant. (Sorry,
|
||
but that uses a lot of time ... 10 up to 30 minutes are not unusual ... but this has
|
||
to be done only once :-). A cvs update doesn't use a modulename but you have to be
|
||
inside the directory. Therefore we go into that on <b>//3</b> and do the update
|
||
on <b>//4</b>.</p>
|
||
|
||
<p>Now we will build our Ant distribution and do a test. So we can see if there
|
||
are any tests failing on our machine. (We can ignore these failing tests on later
|
||
steps; windows syntax used here- translate to xNIX if needed):
|
||
<pre class="output">
|
||
ANTHOME> build // 1
|
||
ANTHOME> set ANT_HOME=%CD%\dist // 2
|
||
ANTHOME> ant test -Dtest.haltonfailure=false // 3
|
||
</pre>
|
||
|
||
First we have to build our Ant distribution (<b>//1</b>). On <b>//2</b> we set the ANT_HOME
|
||
environment variable to the directory where the new created distribution is stored
|
||
(%CD% is expanded to the current directory on Windows 2000 and XP, on 9x and NT
|
||
write it out). On <b>//3</b> we let Ant do all the tests (which enforced a compile
|
||
of all tests) without stopping on first failure.</p>
|
||
|
||
<p>Next we apply our work onto Ants sources. Because we haven't modified any, this is
|
||
a relative simple step. <i>(Because I have a local copy of Ant and usually contribute my
|
||
work, I work on the local copy just from the beginning. The advantage: this step isn't
|
||
necessary and saves a lot of work if you modify existing source :-)</i>.
|
||
|
||
<ul>
|
||
<li>move the Find.java to ANTHOME/src/main/org/apache/tools/ant/taskdefs/Find.java </li>
|
||
<li>move the FindTest.java to ANTHOME/src/testcases/org/apache/tools/ant/taskdefs/FindTest.java </li>
|
||
<li>move the build.xml to ANTHOME/src/etc/testcases/taskdefs/<b>find.xml</b> (!!! renamed !!!)</li>
|
||
<li>add a <tt>package org.apache.tools.ant.taskdefs;</tt> at the beginning of the two java files </li>
|
||
<li>delete all stuff from find.xml keeping the targets "testFileNotPresent", "testFilePresent",
|
||
"test.init" and "testMultipleFiles" </li>
|
||
<li>delete the dependency to "use.init" in the find.xml </li>
|
||
<li>in FindTest.java change the line <tt>configureProject("build.xml");</tt> to
|
||
<tt>configureProject("src/etc/testcases/taskdefs/find.xml");</tt> </li>
|
||
<li>move the find.html to ANTHOME/docs/manual/CoreTasks/find.html </li>
|
||
<li>add a <tt><a href="CoreTasks/find.html">Find</a><br></tt>
|
||
in the ANTHOME/docs/manual/coretasklist.html </li>
|
||
</ul>
|
||
|
||
Now our modifications are done and we will retest it:
|
||
<pre class="output">
|
||
ANTHOME> build
|
||
ANTHOME> ant run-single-test // 1
|
||
-Dtestcase=org.apache.tools.ant.taskdefs.FindTest // 2
|
||
-Dtest.haltonfailure=false
|
||
</pre>
|
||
Because we only want to test our new class, we use the target for single tests, specify
|
||
the test to use and configure not to halt on the first failure - we want to see all
|
||
failures of our own test (<b>//1 + 2</b>).</p>
|
||
|
||
<p>And ... oh, all tests fail: <i>Ant could not find the task or a class this task relies upon.</i></p>
|
||
|
||
<p>Ok: in the earlier steps we told Ant to use the Find class for the <code><find></code> task (remember the
|
||
<code><taskdef></code> statement in the "use.init" target). But now we want to introduce that task as
|
||
a core task. And nobody wants to taskdef the javac, echo, ... So what to do? The answer is the
|
||
src/main/.../taskdefs/default.properties. Here is the mapping between taskname and implementing
|
||
class done. So we add a <tt>find=org.apache.tools.ant.taskdefs.Find</tt> as the last core
|
||
task (just before the <tt># optional tasks</tt> line). Now a second try:
|
||
<pre class="output">
|
||
ANTHOME> build // 1
|
||
ANTHOME> ant run-single-test
|
||
-Dtestcase=org.apache.tools.ant.taskdefs.FindTest
|
||
-Dtest.haltonfailure=false
|
||
</pre>
|
||
We have to rebuild (<b>//1</b>) Ant because the test look in the %ANT_HOME%\lib\ant.jar
|
||
(more precise: on the classpath) for the properties file. And we have only modified it in the
|
||
source path. So we have to rebuild that jar. But now all tests pass and we check whether our class
|
||
breaks some other tests.
|
||
<pre class="output">
|
||
ANTHOME> ant test -Dtest.haltonfailure=false
|
||
</pre>
|
||
Because there are a lot of tests this step requires a little bit of time. So use the <i>run-single-test</i>
|
||
during development and do the <i>test</i> only at the end (maybe sometimes during development too).
|
||
We use the <i>-Dtest.haltonfailure=false</i> here because there could be other tests fail and we have
|
||
to look into them.</p>
|
||
|
||
<p>This test run should show us two things: our test will run and the number of failing tests
|
||
is the same as directly after the cvs update (without our modifications).</p>
|
||
|
||
|
||
|
||
<h3>Apache copyright and license statement</h3>
|
||
<p>Simply copy the license text from one the other source from the Ant source tree. But
|
||
ensure that the current year is used in the<tt> * Copyright (c) 2000-2005 The Apache Software
|
||
Foundation. All rights reserved.</tt> lines. Don't forget to add a license statement at the end
|
||
of the find.html. (Can be copied from other manual files.)</p>
|
||
|
||
|
||
<h3>Test on JDK 1.2</h3>
|
||
<p>Until version 1.5 Ant must be able to run on a JDK 1.1. With version 1.6 this is not a
|
||
requisite any more. But JDK 1.2 is a must-to-work-with. So we have to test that. You can download older
|
||
JDKs from <a href="http://java.sun.com/products/archive/index.html">Sun [9]</a>.</p>
|
||
|
||
<p>Clean the ANT_HOME variable, delete the <i>build, bootstrap</i> and <i>dist</i> directory
|
||
and point JAVA_HOME to the JDK 1.2 home directory. Then do the <tt>build</tt>, set ANT_HOME
|
||
and run <tt>ant test</tt> (like above).</p>
|
||
|
||
<p>Our test should pass.</p>
|
||
|
||
|
||
|
||
<h3>Checkstyle</h3>
|
||
<p>There are many things we have to ensure. Indentation with 4 spaces, blanks here and there, ...
|
||
(all described in the <a href="../ant_task_guidelines.html">Ant Task Guidelines [7]</a> which
|
||
includes the <a href="http://java.sun.com/docs/codeconv/html/CodeConvTOC.doc.html">Sun code style
|
||
[10]</a>). Because there are so many things we would be happy to have a tool for do the checks.
|
||
There is one: checkstyle. Checkstyle is available at <a href="http://checkstyle.sourceforge.net/">
|
||
Sourceforge [11]</a> and Ant provides with the <tt>check.xml</tt> a buildfile which will do the job
|
||
for us.</p>
|
||
|
||
<p>Download it and put the checkstyle-*-all.jar into your %USERPROFILE%\.ant\lib directory.
|
||
All jar's stored there are available to Ant so you haven't to add it to you %ANT_HOME%\lib
|
||
directory (this feature was added with Ant 1.6).</p>
|
||
|
||
<p>So we will run the tests with
|
||
<pre class="output">
|
||
ANTHOME> ant -f check.xml checkstyle htmlreport
|
||
</pre>
|
||
I prefer the HTML report because there are lots of messages and we can navigate faster.
|
||
Open the ANTHOME/build/reports/checkstyle/html/index.html and navigate to the Find.java. Now we
|
||
see that there are some errors: missing whitespaces, unused imports, missing javadocs. So we have
|
||
to do that.</p>
|
||
|
||
<p>Hint: start at the <b>buttom</b> of the file so the line numbers in the report will keep
|
||
up to date and you will find the next error place much more easier without redoing the checkstyle.</p>
|
||
|
||
<p>After cleaning up the code according to the messages we delete the reports directory and
|
||
do a second checkstyle run. Now our task isn't listed. That's fine :-)</p>
|
||
|
||
|
||
|
||
<!--
|
||
Couldnt create the diff that way for myself, but that should be documented.
|
||
But on the other hand this tutorial should not be forgotten any longer so I
|
||
comment that out. JHM
|
||
<h3>Creating the diff</h3>
|
||
<p>Creating a diff for Ant is very easy: just start <tt>ant -f patch.xml</tt> and all is done
|
||
automatically. This step requires a cvs executable in your path and internet access (more precise:
|
||
cvs access). As a result we get a file <i> XXX </i>.</p>
|
||
-->
|
||
|
||
|
||
<h3>Publish the task</h3>
|
||
<p>Finally we publish that archive. As described in the <a href="../ant_task_guidelines.html">
|
||
Ant Task Guidelines [7]</a> we can post it on the developer mailinglist or we create a BugZilla
|
||
entry. For both we need some information:</p>
|
||
|
||
<table border="1">
|
||
<tr>
|
||
<th>subject</th>
|
||
<td><i>short description</i></td>
|
||
<td>Task for finding files in a path</td>
|
||
</tr>
|
||
<tr>
|
||
<th>body</th>
|
||
<td><i>more details about the path</i></td>
|
||
<td>This new task looks inside a nested <code><path/></code> for occurrences of a file and stores
|
||
all locations as a property. See the included manual for details.</td>
|
||
</tr>
|
||
<tr>
|
||
<th>attachements</th>
|
||
<td><i>all files needed to apply the path</td>
|
||
<td>Archive containing a patch with the new and modified resources</td>
|
||
</tr>
|
||
</table>
|
||
|
||
<p>Sending an email with these information is very easy and I think I haven't to show that.
|
||
The other way - BugZilla - is slightly more difficult. But it has the advantage that entries
|
||
will not be forgotten (once per week a report is generated). So I will show this way.</p>
|
||
|
||
<p>You must have a BugZilla account for that. So open the <a href="http://issues.apache.org/bugzilla/">
|
||
BugZilla Main Page [12]</a> and follow the link
|
||
<a href="http://issues.apache.org/bugzilla/createaccount.cgi">Open a new Bugzilla account [13]</a>
|
||
and the steps described there if you haven't one.</p>
|
||
|
||
<ol>
|
||
<li>From the BugZilla main page choose <a href="http://issues.apache.org/bugzilla/enter_bug.cgi">Enter
|
||
a new bug report [14]</a></li>
|
||
<li>Choose "Ant" as product </li>
|
||
<li>Version is the last "Alpha (nightly)" (at this time 1.7)</li>
|
||
<li>Component is "Core tasks"</li>
|
||
<li>Plattform and Severity are ok with "Other" and "Normal"</li>
|
||
<li>Initial State is ok with "New"</li>
|
||
<li>Same with the empy "Assigned to"</li>
|
||
<li>It is not required to add yourself as CC, because you are the reporter and therefore will be
|
||
informed on changes</li>
|
||
<li>URL: no url required</li>
|
||
<li>Summary: add the <i>subject</i> from the table</li>
|
||
<li>Description: add the <i>body</i> from the table</li>
|
||
<li>Then press "Commit"</li>
|
||
<li>After redirecting to the new created bug entry click "Create a New Attachment"</li>
|
||
<li>Enter the path to your local path file into "File" or choose it via the "File"'s
|
||
button.</li>
|
||
<li>Enter a short description into "Description", so that you could guess, what the
|
||
path file includes. Here we could add "Initial Patch".</li>
|
||
<li>The "Content Type" is "auto-detect". You could use the "patch" type, if you only
|
||
provide a single path file, but we want do upload more that one, included in our
|
||
patch.zip.</li>
|
||
<li>Then press "Commit"</li>
|
||
</ol>
|
||
Now the new task is uploaded into the bug database.
|
||
|
||
|
||
<a name="resources"/>
|
||
<h2>Resources</h2>
|
||
[1] <a href="tutorial-writing-tasks.html">tutorial-writing-tasks.html</a><br/>
|
||
[2] <a href="tutorial-tasks-filesets-properties.zip">tutorial-tasks-filesets-properties.zip</a><br/>
|
||
[3] <a href="using.html#built-in-props">using.html#built-in-props</a><br/>
|
||
[4] <a href="http://ant-contrib.sourceforge.net/">http://ant-contrib.sourceforge.net/</a><br/>
|
||
[5] <a href="CoreTasks/java.html">CoreTasks/java.html</a><br/>
|
||
[6] <a href="CoreTasks/find.html">CoreTasks/find.html</a><br/>
|
||
[7] <a href="../ant_task_guidelines.html">../ant_task_guidelines.html</a><br/>
|
||
[8] <a href="http://ant.apache.org/cvs.html">http://ant.apache.org/cvs.html</a><br/>
|
||
[9] <a href="http://java.sun.com/products/archive/index.html">http://java.sun.com/products/archive/index.html</a><br/>
|
||
[10] <a href="http://java.sun.com/docs/codeconv/html/CodeConvTOC.doc.html">http://java.sun.com/docs/codeconv/html/CodeConvTOC.doc.html</a><br/>
|
||
[11] <a href="http://checkstyle.sourceforge.net/">http://checkstyle.sourceforge.net/</a><br/>
|
||
[12] <a href="http://issues.apache.org/bugzilla/">http://issues.apache.org/bugzilla/</a><br/>
|
||
[13] <a href="http://issues.apache.org/bugzilla/createaccount.cgi">http://issues.apache.org/bugzilla/createaccount.cgi</a><br/>
|
||
[14] <a href="http://issues.apache.org/bugzilla/enter_bug.cgi">http://issues.apache.org/bugzilla/enter_bug.cgi</a><br/>
|
||
|
||
|
||
<!--
|
||
TODO:
|
||
- how to create a path (path.xml / command line)
|
||
-->
|
||
|
||
|
||
|
||
<hr>
|
||
<p align="center">Copyright © 2003-2005 The Apache Software Foundation. All rights
|
||
Reserved.</p>
|
||
|
||
</body>
|
||
</html>
|