Enhance build scripts to check for up-to-date artifacts before creation

Don't rebuild jars if nothing changed!

See #2233

Author: iloveeclipse

apitools/org.eclipse.pde.api.tools/scripts/buildApiToolsAntSupportJar.xml

@@ -1,13 +1,13 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <!--
 	Copyright (c) IBM Corporation and others 2008, 2013 This page is made available under license. For full details see the LEGAL in the documentation book that contains this page.
-	
+
 	All Platform Debug contexts, those for org.eclipse.debug.ui, are located in this file
 	All contexts are grouped by their relation, with all relations grouped alphabetically.
 -->
 <project name="Build API Tools Ant Support Jar" default="build" basedir="..">
 
-	<target name="build" description="Cleans, builds and refreshes" depends="clean, lib/apitooling-ant.jar"/>
+	<target name="build" description="Builds if needed" depends="lib/apitooling-ant.jar"/>
 
 	<target name="init" depends="properties">
 		<property name="temp.folder" value="${basedir}/temp.folder"/>
@@ -17,15 +17,30 @@
 	<target name="properties" if="eclipse.running">
 		<property name="build.compiler" value="org.eclipse.jdt.core.JDTCompilerAdapter"/>
 	</target>
-			
-	<target name="lib/apitooling-ant.jar" description= "Creates the lib/apitooling-ant.jar" depends="init">
+
+	<target name="check.uptodate" depends="init">
+		<!-- Check if the jar is up-to-date with respect to all source inputs -->
+		<uptodate property="lib/apitooling-ant.jar.uptodate"
+				targetfile="${build.result.folder}/lib/apitooling-ant.jar">
+			<srcresources>
+				<fileset dir="${basedir}/src_ant/"/>
+				<fileset dir="xml/">
+					<exclude name="**/*.xsd"/>
+					<exclude name="**/*.xml"/>
+				</fileset>
+			</srcresources>
+		</uptodate>
+	</target>
+
+	<target name="lib/apitooling-ant.jar" description="Creates the lib/apitooling-ant.jar"
+			depends="check.uptodate" unless="lib/apitooling-ant.jar.uptodate">
 		<property name="destdir" value="${temp.folder}/lib/apitooling-ant.bin"/>
 		<delete dir="${destdir}"/>
 		<mkdir dir="${destdir}"/>
 		<!-- copy necessary resources -->
-        <copy todir="${destdir}">
-            <fileset dir="${basedir}/bin_ant/"/>
-        </copy>
+		<copy todir="${destdir}">
+			<fileset dir="${basedir}/bin_ant/"/>
+		</copy>
 		<!-- copy default XSLT files to the jar location -->
 		<copy todir="${destdir}" failonerror="true" overwrite="false">
 			<fileset dir="xml/">

build/org.eclipse.pde.build/localbuild.xml

@@ -8,7 +8,7 @@
      https://www.eclipse.org/legal/epl-2.0/
 
      SPDX-License-Identifier: EPL-2.0
-    
+
      Contributors:
          IBM Corporation - initial API and implementation
  -->
@@ -19,25 +19,31 @@
     	 gathering up the results of a workspace build from bin_ant.
     </description>
 
-	<!-- ================================= 
-          target: default              
+	<!-- =================================
+          target: default
          ================================= -->
-	<target name="default" description="--> description">
+	<target name="default" depends="checkSourceUpToDate" unless="pdebuild-ant.jar.uptodate"
+		description="Build pdebuild-ant.jar from source if needed">
 		<tstamp/>
-		<eclipse.buildScript elements="plugin@org.eclipse.pde.build" 
-			buildDirectory="${buildDirectory}" 
-			configInfo="*,*,*" 
-			baseLocation="${baseLocation}" 
+		<eclipse.buildScript elements="plugin@org.eclipse.pde.build"
+			buildDirectory="${buildDirectory}"
+			configInfo="*,*,*"
+			baseLocation="${baseLocation}"
 			outputUpdateJars="false"
 			pluginpath="${thisPlugin}"
 			forceContextQualifier="z${DSTAMP}${TSTAMP}"
 			/>
-		<delete file="lib/pdebuild-ant.jar" failonerror="false"/>
 		<ant antfile="build.xml" target="lib/pdebuild-ant.jar"/>
 	</target>
-	<target name="workspaceBinaries" description="Jar up the binaries that were compiled by the jdt builder" >
+	<target name="checkSourceUpToDate">
+		<uptodate property="pdebuild-ant.jar.uptodate" targetfile="lib/pdebuild-ant.jar">
+			<srcfiles dir="src_ant" includes="**/*"/>
+		</uptodate>
+	</target>
+
+	<target name="workspaceBinaries" depends="checkSourceUpToDate" unless="pdebuild-ant.jar.uptodate"
+		description="Jar up the binaries that were compiled by the jdt builder">
 		<mkdir dir="lib" />
-		<delete file="lib/pdebuild-ant.jar" failonerror="false"/>
 		<jar destfile="lib/pdebuild-ant.jar" basedir="bin_ant"/>
 	</target>
 </project>

ui/org.eclipse.pde.core/localbuild.xml

@@ -22,7 +22,8 @@
 	<!-- =================================
           target: default
          ================================= -->
-	<target name="default" description="--> description">
+	<target name="default" depends="checkSourceUpToDate" unless="pde-ant.jar.uptodate"
+		description="Build pde-ant.jar from scratch if sources have changed">
 		<tstamp/>
 		<eclipse.buildScript elements="plugin@org.eclipse.pde.core"
 			buildDirectory="${buildDirectory}"
@@ -33,12 +34,19 @@
 			pluginpath="${thisPlugin}"
 			forceContextQualifier="z${DSTAMP}${TSTAMP}"
 			/>
-		<delete file="ant_tasks/pde-ant.jar" failonerror="false"/>
 		<ant antfile="build.xml" target="ant_tasks/pde-ant.jar"/>
 	</target>
-	<target name="workspaceBinaries" description="Jar up the binaries that were compiled by the jdt builder" >
+
+	<target name="checkSourceUpToDate">
+		<uptodate property="pde-ant.jar.uptodate" targetfile="ant_tasks/pde-ant.jar">
+			<srcfiles dir="src_ant" includes="**/*"/>
+		</uptodate>
+	</target>
+
+	<target name="workspaceBinaries" depends="checkSourceUpToDate" unless="pde-ant.jar.uptodate"
+		description="Jar up the binaries that were compiled by the jdt builder">
 		<mkdir dir="ant_tasks" />
-		<delete file="ant_tasks/pde-ant.jar" failonerror="false"/>
 		<jar destfile="ant_tasks/pde-ant.jar" basedir="binary"/>
 	</target>
+
 </project>