Developing a build.xml File for Building Struts Applications Using AntThis section is based on the strutsANT.zip file that's included on the CD-ROM accompanying this book. Other sections of this chapter use different archives. A good Ant build file enables you to build as much or as little of the application as you want. It also lets you pick up where you left off without repeating steps. And ”if you want to ”it should let you delete everything (hopefully except your source files!) and start over from scratch. In reality, Ant build files can be created to do virtually anything you can write a program for. People all over the world have added tasks to Ant to do anything that's commonly needed. If all else fails, Ant is completely extendable by using Java to write your own tasks . This chapter, however, sticks with the basics of how to build a Struts application. Listing 20.1 is the build file used in this sample application. Don't worry about understanding every line right now; each part of it is explained as you progress through this section. The name of the build file is build.xml because this is the default name that Ant looks for if you just type ant without specifying a particular build file by name. Listing 20.1 The Ant Build File for the Hello World! Sample Application ( build.xml )<project name="billing" default="help" basedir="."> <!-- ===================== Property Definitions =========================== --> <!-- All properties should be defined in this section. Any host-specific properties should be defined in the build.properties file. In this app, the following properties are defined in build.properties: o tomcat.home - the home directory of your Tomcat installation o webapps.home - the place to copy the war file to deploy it --> <property file="build.properties" /> <property name="app.home" value="." /> <property name="app.name" value="strutsANT" /> <property name="javadoc.pkg.top" value="ch20" /> <property name="src.home" value="${app.home}/src"/> <property name="lib.home" value="${app.home}/lib"/> <property name="object.home" value="${app.home}/object"/> <property name="deploy.home" value="${app.home}/deploy"/> <property name="doc.home" value="${app.home}/doc"/> <property name="web.home" value="${app.home}/web"/> <property name="build.home" value="${app.home}/build"/> <property name="build.classes" value="${build.home}/WEB-INF/classes"/> <property name="build.lib" value="${build.home}/WEB-INF/lib"/> <!-- ==================== Compilation Classpath =========================== --> <!-- This section creates the classpath for compilation. --> <path id="compile.classpath"> <!-- The object files for this application --> <pathelement location="${object.home}"/> <!-- The lib files for this application --> <fileset dir="${lib.home}"> <include name="*.jar"/> <include name="*.zip"/> </fileset> <!-- All files/jars that Tomcat makes available --> <fileset dir="${tomcat.home}/lib"> <include name="*.jar"/> </fileset> <fileset dir="${tomcat.home}/common/lib"> <include name="*.jar"/> </fileset> <pathelement location="${tomcat.home}/classes"/> <pathelement location="${tomcat.home}/common/classes"/> </path> <!-- ==================== Build Targets below here========================= --> <!-- ==================== "help" Target =================================== --> <!-- This is the default ant target executed if no target is specified. This helps avoid users just typing 'ant' and running a default target that may not do what they are anticipating... --> <target name="help" > <echo message="Please specify a target! [usage: ant <targetname>]" /> <echo message="Here is a list of possible targets: "/> <echo message=" clean-all.....Delete build dir, all .class and war files"/> <echo message=" prepare.......Creates directories if required" /> <echo message=" compile.......Compiles source files" /> <echo message=" build.........Build war file from .class and other files"/> <echo message=" deploy........Copy war file to the webapps directory" /> <echo message=" javadoc.......Generates javadoc for this application" /> </target> <!-- ==================== "clean-all" Target ============================== --> <!-- This target should clean up any traces of the application so that if you run a new build directly after cleaning, all files will be replaced with what's current in source control --> <target name="clean-all" > <delete dir="${build.home}"/> <delete dir="${object.home}"/> <delete dir="${deploy.home}"/> <!-- can't delete directory if Tomcat is running --> <delete dir="${webapps.home}/${app.name}" failonerror="false"/> <!-- deleting the deployed .war file is fine even if Tomcat is running --> <delete dir="${webapps.home}/${app.name}.war" /> <!-- delete the javadoc --> <delete dir="${doc.home}"/> </target> <!-- ==================== "prepare" Target ================================ --> <!-- This target is executed prior to any of the later targets to make sure the directories exist. It only creates them if they need to be created.... Other, similar, preparation steps can be placed here. --> <target name="prepare"> <echo message="Tomcat Home = ${tomcat.home}" /> <echo message="webapps Home = ${webapps.home}" /> <mkdir dir="${object.home}"/> <mkdir dir="${deploy.home}"/> <mkdir dir="${doc.home}"/> <mkdir dir="${doc.home}/api"/> <mkdir dir="${build.home}"/> <mkdir dir="${build.home}/WEB-INF" /> <mkdir dir="${build.home}/WEB-INF/classes" /> <mkdir dir="${build.home}/WEB-INF/lib" /> </target> <!-- ==================== "compile" Target ================================ --> <!-- This only compiles java files that are newer than their corresponding .class files. --> <target name="compile" depends="prepare" > <javac srcdir="${src.home}" destdir="${object.home}" debug="yes" > <classpath refid="compile.classpath"/> </javac> </target> <!-- ==================== "build" Target ================================== --> <!-- This target builds the war file for the application by first building the directory structure of the application in ${build.home} and then creating the war file using the ant <war> task --> <target name="build" depends="compile" > <!-- Copy all the webapp content (jsp's, html, tld's, xml, etc. --> <!-- Note that this also copies the META-INF directory --> <copy todir="${build.home}"> <fileset dir="${web.home}"/> </copy> <!-- Now, copy all the Java class files --> <copy todir="${build.home}/WEB-INF/classes"> <fileset dir="${object.home}"/> </copy> <!-- Now, copy all the properties files, etc that go on the classpath --> <copy todir="${build.home}/WEB-INF/classes"> <fileset dir="${src.home}"> <include name="**/*.properties" /> <include name="**/*.prop" /> </fileset> </copy> <!-- Now, copy all the jar files we need --> <copy todir="${build.home}/WEB-INF/lib"> <fileset dir="${lib.home}" /> </copy> <!-- Create the <war> file --> <jar jarfile="${deploy.home}/${app.name}.war" basedir="${build.home}"/> </target> <!-- ==================== "deploy" Target ================================= --> <!-- This target simply copies the war file from the deploy directory into the Tomcat webapp directory. --> <target name="deploy" depends="build" > <!-- Copy the contents of the build directory --> <copy todir="${webapps.home}" file="${deploy.home}/${app.name}.war" /> </target> <!-- ==================== "doc" Target ==================================== --> <!-- This task creates javadoc. It is dependent upon only the 'compile' target so it is not executed in a normal build. As a result, the target needs to be run on its own. --> <target name="javadoc" depends="compile"> <javadoc sourcepath = "${src.home}" destdir = "${doc.home}/api" packagenames = "${javadoc.pkg.top}.*"/> </target> </project> The following items summarize each section of the build.xml file:
Now that you've got a directory structure for developing your application and an Ant build file for building and compiling, it's time to focus on the more "extreme" elements of this chapter: how to make integrated and ongoing testing a part of your everyday development cycle. |