Ant build file path element

Let us create our first task. Before learning Apache Ant, one must understand the need for a build tool. Why do we need Ant, or more specifically, why do we need a build tool?

The "Build" is a process that covers all the steps required to create a "deliverable" of your software. In the Java world, this typically includes:. Open the command prompt and navigate to the folder where the build.

You should see the following output:. Project :-The project is the root element of the build file, it contains one or more targets. The default attribute is required and specifies the default build target in this case: "hello". Target :- A target represents a project milestone in ant, it contains zero or more tasks. The name attribute is required and specifies the name of the target in this case: "hello". Task echo in this case :- Tasks are the smallest units of work in ant. Ant - Build Files Advertisements.

Previous Page. Next Page. Useful Video Courses. More Detail. Anatomy of Floering Plant 19 Lectures 2. Morphology of Flowering Plants 30 Lectures 1. Determinants 65 Lectures 6. When you do this they are evaluated before any targets are executed. We have given some targets descriptions; this causes the -projecthelp invocation option to list them as public targets with the descriptions; the other target is internal and not listed.

Finally, for this target to work the source in the src subdirectory should be stored in a directory tree which matches the package names. A project can have a set of tokens that might be automatically expanded if found when a file is copied, when the filtering-copy behavior is selected in the tasks that support this. These might be set in the buildfile by the filter task.

This token syntax matches the syntax of other build systems that perform such filtering and remains sufficiently orthogonal to most programming and scripting languages, as well as with documentation systems. Note : If a token with the format token is found in a file, but no filter is associated with that token, no changes take place; therefore, no escaping method is available—but as long as you choose appropriate names for your tokens, this should not cause problems.

Warning : If you copy binary files with filtering turned on, you can corrupt the files. This feature should be used with text files only.

Ant will convert the separator to the correct character of the current operating system. Wherever path-like values need to be specified, a nested element can be used. This takes the general form of:. The location attribute specifies a single file or directory relative to the project's base directory or an absolute filename , while the path attribute accepts colon- or semicolon-separated lists of locations.

The path attribute is intended to be used with predefined paths—in any other case, multiple elements with location attributes should be preferred. In addition, one or more resource collections can be specified as nested elements these must consist of file -type resources only.

Additionally, it should be noted that although resource collections are processed in the order encountered, certain resource collection types such as fileset , dirset and files are undefined in terms of order. By default a path-like structure will re-evaluate all nested resource collections whenever it is used, which may lead to unnecessary re-scanning of the filesystem.

Even if you are using the path only in a single task it may improve overall performance to set cache to true if you are using complex nested constructs. 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. If you have a look at the manual page of the Java task [5] you will see that it:. The Ant Task Guidelines [6] support additional information on that.

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: org.

Now we integrate our work into Ant distribution. So first we do an update of our Git tree. If not done yet, you should clone the Ant repository on GitHub[7], then create a local clone:. 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 UNIX if needed :. Next we apply our work onto Ant sources. Because we haven't modified any, this is a relatively simple step. Because I have a local Git clone 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 sources But now we want to introduce that task as a core task. And nobody wants to taskdef the javac , echo , Here is the mapping between taskname and implementing class done. Find as the last core task just before the optional tasks line. Now a second try:. 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.

Because there are a lot of tests this step requires a little bit of time. So use the run-single-test during development and do the test only at the end maybe sometimes during development too.

We use the -Dtest. This test run should show us two things: our test will run and the number of failing tests is the same as directly after git clone without our modifications. Ant 1. That means that updates to Ant code present in Ant 1. It is fine to address only ant 1.

So we have to test that. You can download older JDKs from Oracle [8]. Then create the patch with your commit, checkout 1.