Refactoring of android_rules.xml file

This is a new CL because of merge conflict in the old one.
Naming changed to 'property.name' style for property names.
Property 'value' attributes changed to 'location' for props containing location.
Suffix '.dir' added to properties' names indicating directories.
'-description' prefix added to intermediate/internal targets.
'*.location' properties removed, as 'location' attribute should take care of
full paths, adding $basedir implicitly, so hopefully there is no need to
define them explicitly.
External property names (taken from other files or hardcoded somewhere)
stayed untouched in this CL.
Some minor improvements to comments in order to make them more consistent.
diff --git a/tools/scripts/android_rules.xml b/tools/scripts/android_rules.xml
index de44a7e..b8a5380 100644
--- a/tools/scripts/android_rules.xml
+++ b/tools/scripts/android_rules.xml
@@ -24,176 +24,169 @@
 
     <!-- Properties -->
 
-    <property name="android-tools" value="${sdk-location}/tools" />
+    <property name="android.tools.dir" location="${sdk-location}/tools" />
 
     <!-- Input directories -->
-    <property name="source-folder" value="src" />
-    <property name="gen-folder" value="gen" />
-    <property name="resource-folder" value="res" />
-    <property name="asset-folder" value="assets" />
-    <property name="source-location" value="${basedir}/${source-folder}" />
+    <property name="source.dir" location="src" />
+    <property name="gen.dir" location="gen" />
+    <property name="resource.dir" location="res" />
+    <property name="asset.dir" location="assets" />
 
-    <!-- folder for the 3rd party java libraries -->
-    <property name="external-libs-folder" value="libs" />
+    <!-- Directory for the 3rd party java libraries -->
+    <property name="external.libs.dir" location="libs" />
 
-    <!-- folder for the native libraries -->
-    <property name="native-libs-folder" value="libs" />
+    <!-- Directory for the native libraries -->
+    <property name="native.libs.dir" location="libs" />
 
     <!-- Output directories -->
-    <property name="gen-folder" value="gen" />
-    <property name="out-folder" value="bin" />
-    <property name="out-classes" value="${out-folder}/classes" />
-    <property name="out-classes-location" value="${basedir}/${out-classes}"/>
-    <!-- out folders for a parent project if this project is an instrumentation project -->
-    <property name="main-out-folder" value="../${out-folder}" />
-    <property name="main-out-classes" value="${main-out-folder}/classes"/>
+    <property name="gen.dir" location="gen" />
+    <property name="out.dir" location="bin" />
+    <property name="out.classes.dir" location="${out.dir}/classes" />
+
+    <!-- Out directory for a parent project if this project is an instrumentation project -->
+    <property name="main.out.dir" location="../${out.dir}" />
+    <property name="main.out.classes.dir" location="${main.out.dir}/classes"/>
 
     <!-- Intermediate files -->
-    <property name="dex-file" value="classes.dex" />
-    <property name="intermediate-dex" value="${out-folder}/${dex-file}" />
-    <!-- dx does not properly support incorrect / or \ based on the platform
-         and Ant cannot convert them because the parameter is not a valid path.
-         Because of this we have to compute different paths depending on the platform. -->
-    <condition property="intermediate-dex-location"
-            value="${basedir}\${intermediate-dex}"
-            else="${basedir}/${intermediate-dex}" >
-        <os family="windows"/>
-    </condition>
+    <property name="dex.file.name" value="classes.dex" />
+    <property name="intermediate.dex.file" location="${out.dir}/${dex.file.name}" />
 
     <!-- The final package file to generate -->
-    <property name="out-debug-unaligned-package" value="${out-folder}/${ant.project.name}-debug-unaligned.apk"/>
-    <property name="out-debug-package" value="${out-folder}/${ant.project.name}-debug.apk"/>
-    <property name="out-unsigned-package" value="${out-folder}/${ant.project.name}-unsigned.apk"/>
-    <property name="out-unaligned-package" value="${out-folder}/${ant.project.name}-unaligned.apk"/>
-    <property name="out-release-package" value="${out-folder}/${ant.project.name}-release.apk"/>
+    <property name="out.debug.unaligned.package" location="${out.dir}/${ant.project.name}-debug-unaligned.apk"/>
+    <property name="out.debug.package" location="${out.dir}/${ant.project.name}-debug.apk"/>
+    <property name="out.unsigned.package" location="${out.dir}/${ant.project.name}-unsigned.apk"/>
+    <property name="out.unaligned.package" location="${out.dir}/${ant.project.name}-unaligned.apk"/>
+    <property name="out.release.package" location="${out.dir}/${ant.project.name}-release.apk"/>
 
     <!-- Tools -->
     <condition property="exe" value=".exe" else=""><os family="windows"/></condition>
-    <property name="adb" value="${android-tools}/adb${exe}"/>
-    <property name="zipalign" value="${android-tools}/zipalign${exe}" />
+    <property name="adb" location="${android.tools.dir}/adb${exe}"/>
+    <property name="zipalign" location="${android.tools.dir}/zipalign${exe}" />
 
-    <!-- rules -->
+    <!-- Rules -->
 
-    <!-- Create the output directories if they don't exist yet. -->
-    <target name="dirs">
+    <!-- Creates the output directories if they don't exist yet. -->
+    <target name="-dirs">
         <echo>Creating output directories if needed...</echo>
-        <mkdir dir="${resource-folder}" />
-        <mkdir dir="${external-libs-folder}" />
-        <mkdir dir="${gen-folder}" />
-        <mkdir dir="${out-folder}" />
-        <mkdir dir="${out-classes}" />
+        <mkdir dir="${resource.dir}" />
+        <mkdir dir="${external.libs.dir}" />
+        <mkdir dir="${gen.dir}" />
+        <mkdir dir="${out.dir}" />
+        <mkdir dir="${out.classes.dir}" />
     </target>
 
-    <!-- Generate the R.java file for this project's resources. -->
-    <target name="resource-src" depends="dirs">
+    <!-- Generates the R.java file for this project's resources. -->
+    <target name="-resource-src" depends="-dirs">
         <echo>Generating R.java / Manifest.java from the resources...</echo>
         <exec executable="${aapt}" failonerror="true">
             <arg value="package" />
             <arg value="-m" />
             <arg value="-J" />
-            <arg path="${gen-folder}" />
+            <arg path="${gen.dir}" />
             <arg value="-M" />
             <arg path="AndroidManifest.xml" />
             <arg value="-S" />
-            <arg path="${resource-folder}" />
+            <arg path="${resource.dir}" />
             <arg value="-I" />
             <arg path="${android-jar}" />
         </exec>
     </target>
 
-    <!-- Generate java classes from .aidl files. -->
-    <target name="aidl" depends="dirs">
+    <!-- Generates java classes from .aidl files. -->
+    <target name="-aidl" depends="-dirs">
         <echo>Compiling aidl files into Java classes...</echo>
         <apply executable="${aidl}" failonerror="true">
             <arg value="-p${android-aidl}" />
-            <arg value="-I${source-folder}" />
-            <arg value="-o${gen-folder}" />
-            <fileset dir="${source-folder}">
+            <arg value="-I${source.dir}" />
+            <arg value="-o${gen.dir}" />
+            <fileset dir="${source.dir}">
                 <include name="**/*.aidl"/>
             </fileset>
         </apply>
     </target>
 
-    <!-- Compile this project's .java files into .class files. -->
-    <target name="compile" depends="resource-src, aidl">
+    <!-- Compiles this project's .java files into .class files. -->
+    <target name="compile" depends="-resource-src, -aidl"
+                description="Compiles project's .java files into .class files">
         <javac encoding="ascii" target="1.5" debug="true" extdirs=""
-                destdir="${out-classes}"
+                destdir="${out.classes.dir}"
                 bootclasspathref="android.target.classpath">
-            <src path="${source-folder}" />
-            <src path="${gen-folder}" />
+            <src path="${source.dir}" />
+            <src path="${gen.dir}" />
             <classpath>
-                <fileset dir="${external-libs-folder}" includes="*.jar"/>
-                <pathelement path="${main-out-classes}"/>
+                <fileset dir="${external.libs.dir}" includes="*.jar"/>
+                <pathelement path="${main.out.classes.dir}"/>
             </classpath>
          </javac>
     </target>
 
-    <!-- Convert this project's .class files into .dex files. -->
-    <target name="dex" depends="compile">
-        <echo>Converting compiled files and external libraries into ${out-folder}/${dex-file}...</echo>
+    <!-- Converts this project's .class files into .dex files -->
+    <target name="-dex" depends="compile">
+        <echo>Converting compiled files and external libraries into ${out.dir}/${dex.file.name}...</echo>
         <apply executable="${dx}" failonerror="true" parallel="true">
             <arg value="--dex" />
-            <arg value="--output=${intermediate-dex-location}" />
-            <arg path="${out-classes-location}" />
-            <fileset dir="${external-libs-folder}" includes="*.jar"/>
+            <arg value="--output=${intermediate.dex.file}" />
+            <arg path="${out.classes.dir}" />
+            <fileset dir="${external.libs.dir}" includes="*.jar"/>
         </apply>
     </target>
 
-    <!-- Put the project's resources into the output package file
+    <!-- Puts the project's resources into the output package file
          This actually can create multiple resource package in case
          Some custom apk with specific configuration have been
          declared in default.properties.
          -->
-    <target name="package-resources">
+    <target name="-package-resources">
         <echo>Packaging resources</echo>
         <aaptexec executable="${aapt}"
                 command="package"
                 manifest="AndroidManifest.xml"
-                resources="${resource-folder}"
-                assets="${asset-folder}"
+                resources="${resource.dir}"
+                assets="${asset.dir}"
                 androidjar="${android-jar}"
-                outfolder="${out-folder}"
+                outfolder="${out.dir}"
                 basename="${ant.project.name}" />
     </target>
 
-    <!-- Package the application and (maybe) sign it with a debug key.
+    <!-- Packages the application and (maybe) sign it with a debug key.
          This requires the property sign.package to be set to true or false. -->
-    <target name="package">
+    <target name="-package">
         <apkbuilder
-                outfolder="${out-folder}"
+                outfolder="${out.dir}"
                 basename="${ant.project.name}"
                 signed="${sign.package}"
                 verbose="true">
-            <file path="${intermediate-dex}" />
-            <sourcefolder path="${source-folder}" />
-            <jarfolder path="${external-libs-folder}" />
-            <nativefolder path="${native-libs-folder}" />
+            <file path="${intermediate.dex.file}" />
+            <sourcefolder path="${source.dir}" />
+            <jarfolder path="${external.libs.dir}" />
+            <nativefolder path="${native.libs.dir}" />
         </apkbuilder>
     </target>
 
-    <target name="no-sign">
+    <target name="-no-sign">
        <property name="sign.package" value="false" />
     </target>
 
-    <target name="debug-sign">
+    <target name="-debug-sign">
        <property name="sign.package" value="true" />
     </target>
 
-    <target name="debug" depends="dex, package-resources, debug-sign, package">
+    <target name="debug" depends="-dex, -package-resources, -debug-sign, -package"
+                description="Builds the application and signs it with a debug key.">
         <echo>Running zip align on final apk...</echo>
         <exec executable="${zipalign}" failonerror="true">
             <arg value="-f" />
             <arg value="4" />
-            <arg path="${out-debug-unaligned-package}" />
-            <arg path="${out-debug-package}" />
+            <arg path="${out.debug.unaligned.package}" />
+            <arg path="${out.debug.package}" />
         </exec>
-        <echo>Debug Package: ${out-debug-package}</echo>
+        <echo>Debug Package: ${out.debug.package}</echo>
     </target>
 
-    <target name="release-package" depends="dex, package-resources, no-sign, package">
+    <target name="-release-package" depends="-dex, -package-resources, -no-sign, -package">
     </target>
 
-    <target name="release.check">
+    <target name="-release-check">
         <condition property="release.sign">
             <and>
                 <isset property="key.store" />
@@ -201,81 +194,90 @@
             </and>
         </condition>
     </target>
-    <target name="release.nosign" depends="release.check" unless="release.sign">
+
+    <target name="-release-nosign" depends="-release-check" unless="release.sign">
         <echo>No key.store and key.alias properties found in build.properties.</echo>
-        <echo>Please sign ${out-unsigned-package} manually</echo>
+        <echo>Please sign ${out.unsigned.package} manually</echo>
         <echo>and run zipalign from the Android SDK tools.</echo>
     </target>
 
-    <target name="release" depends="release-package, release.nosign" if="release.sign">
-        <!-- get passwords -->
+    <target name="release" depends="-release-package, -release-nosign" if="release-sign"
+                description="Builds the application. The generated apk file must be signed before it is published.">
+
+        <!-- Gets passwords -->
         <input
                 message="Please enter keystore password (store:${key.store}):"
                 addproperty="key.store.password"/>
         <input
                 message="Please enter password for alias '${key.alias}':"
                 addproperty="key.alias.password"/>
-        <!-- sign the APK -->
+
+        <!-- Signs the APK -->
         <echo>Signing final apk...</echo>
         <signjar
-                jar="${out-unsigned-package}"
-                signedjar="${out-unaligned-package}"
+                jar="${out.unsigned.package}"
+                signedjar="${out.unaligned.package}"
                 keystore="${key.store}"
                 storepass="${key.store.password}"
                 alias="${key.alias}"
                 keypass="${key.alias.password}"/>
-        <!-- zip align the APK -->
+
+        <!-- Zip aligns the APK -->
         <echo>Running zip align on final apk...</echo>
         <exec executable="${zipalign}" failonerror="true">
             <arg value="-f" />
             <arg value="4" />
-            <arg path="${out-unaligned-package}" />
-            <arg path="${out-release-package}" />
+            <arg path="${out.unaligned.package}" />
+            <arg path="${out.release.package}" />
         </exec>
-        <echo>Release Package: ${out-release-package}</echo>
+        <echo>Release Package: ${out.release.package}</echo>
     </target>
 
-    <!-- Install the package on the default emulator -->
-    <target name="install" depends="debug">
-        <echo>Installing ${out-debug-package} onto default emulator...</echo>
+    <!-- Installs the package on the default emulator/device -->
+    <target name="install" depends="debug"
+                description="Installs the debug package onto a running emulator or device. This can only be used if the application has not yet been installed.">
+        <echo>Installing ${out.debug.package} onto default emulator or device...</echo>
         <exec executable="${adb}" failonerror="true">
             <arg value="install" />
-            <arg path="${out-debug-package}" />
+            <arg path="${out.debug.package}" />
         </exec>
     </target>
 
-    <target name="reinstall" depends="debug">
-        <echo>Installing ${out-debug-package} onto default emulator...</echo>
+    <target name="reinstall" depends="debug" description="Installs the debug package on a running emulator or device that already has the application.">
+        <echo>Installing ${out.debug.package} onto default emulator or device...</echo>
         <exec executable="${adb}" failonerror="true">
             <arg value="install" />
             <arg value="-r" />
-            <arg path="${out-debug-package}" />
+            <arg path="${out.debug.package}" />
         </exec>
     </target>
 
-    <!-- Uinstall the package from the default emulator -->
-    <target name="uninstall.check">
+    <!-- Uninstalls the package from the default emulator/device -->
+    <target name="-uninstall-check">
         <condition property="uninstall.run">
            <isset property="application-package" />
         </condition>
     </target>
-    <target name="uninstall.error" depends="uninstall.check" unless="uninstall.run">
-        <echo>Unable to run 'ant unintall', application-package is not defined in build.properties</echo>
+
+    <target name="-uninstall-error" depends="-uninstall-check" unless="uninstall.run">
+        <echo>Unable to run 'ant uninstall', application-package is not defined in build.properties</echo>
     </target>
-    <target name="uninstall" depends="uninstall.error" if="uninstall.run">
-        <echo>Uninstalling ${application-package} from the default emulator...</echo>
+
+    <target name="uninstall" depends="-uninstall-error" if="uninstall.run" description="Uninstalls the application from a running emulator or device.">
+        <echo>Uninstalling ${application-package} from the default emulator or device...</echo>
         <exec executable="${adb}" failonerror="true">
             <arg value="uninstall" />
             <arg value="${application-package}" />
         </exec>
     </target>
-    
+
     <target name="help">
         <!-- displays starts at col 13
               |13                                                              80| -->
         <echo>Android Ant Build. Available targets:</echo>
         <echo>   help:      Displays this help.</echo>
-        <echo>   debug:     Builds the application and sign it with a debug key.</echo>
+        <echo>   compile:   Compiles project's .java files into .class files.</echo>
+        <echo>   debug:     Builds the application and signs it with a debug key.</echo>
         <echo>   release:   Builds the application. The generated apk file must be</echo>
         <echo>              signed before it is published.</echo>
         <echo>   install:   Installs the debug package onto a running emulator or</echo>
@@ -284,7 +286,7 @@
         <echo>   reinstall: Installs the debug package on a running emulator or</echo>
         <echo>              device that already has the application.</echo>
         <echo>              The signatures must match.</echo>
-        <echo>   uninstall: uninstall the application from a running emulator or</echo>
+        <echo>   uninstall: Uninstalls the application from a running emulator or</echo>
         <echo>              device.</echo>
     </target>
 </project>