--- a/build-defs.xml	Thu Jun 17 10:43:17 2010 -0700
+++ b/build-defs.xml	Thu Jun 17 10:50:14 2010 -0700
@@ -55,9 +55,29 @@
     <drop-import name="jaxp_src"/>
     <!-- <drop-import name="jaxp_tests"/> -->
 
+    <!-- Fail and print helpful messages if source does not exist. -->
+    <target name="-src-help">
+      <fail message="${failed.url.src.message}">
+	<condition>
+	    <and>
+                <not>
+	            <available file="${jaxp_src.src.dir}" type="dir"/>
+	        </not>
+	        <istrue value="${allow.downloads}"/>
+	    </and>
+	</condition>
+      </fail>
+      <fail message="${failed.nourl.src.message}">
+	<condition>
+            <not>
+	        <available file="${jaxp_src.src.dir}" type="dir"/>
+	    </not>
+	</condition>
+      </fail>
+    </target>
 
-    <!-- Special build area preparation. -->
-    <target name="-drop-build-prep" depends="init, -init-src-dirs">
+    <!-- Special build area setup. -->
+    <target name="-drop-build-setup" depends="init, -init-src-dirs">
         <mkdir dir="${build.classes.dir}"/>
         <copy todir="${build.classes.dir}">
             <fileset dir="${primary.src.dir}"
@@ -84,7 +104,7 @@
 
     <!-- Source directory selection. -->
     <target name="-init-src-dirs"
-	    depends="init, -use-drop">
+	    depends="init, -use-drop,-src-help">
         <echo message="Using primary.src.dir=${primary.src.dir}"/>
         <pathconvert property="src.list.id" refid="src.dir.id"/>
         <echo message="Using src.dir.id=${src.list.id}"/>

--- a/build-drop-template.xml	Thu Jun 17 10:43:17 2010 -0700
+++ b/build-drop-template.xml	Thu Jun 17 10:50:14 2010 -0700
@@ -75,6 +75,7 @@
     <target name="-@DROP@-url-should-be-used" unless="@DROP@.url.should.be.used">
         <condition property="@DROP@.url.should.be.used">
             <and>
+                <istrue value="${allow.downloads}"/>
                 <not>
                     <isset property="@DROP@.master.bundle.copy.exists"/>
                 </not>

--- a/build.properties	Thu Jun 17 10:43:17 2010 -0700
+++ b/build.properties	Thu Jun 17 10:50:14 2010 -0700
@@ -104,4 +104,24 @@
   drops.dir=${drops.dir}${line.separator}\
 ${line.separator}
 
+# Failure messages when source cannot be found on the file system
+failed.nourl.src.message=\
+ERROR: Cannot find source for project ${ant.project.name}.\
+${line.separator}${line.separator}\
+HINT: Try setting drops.dir to indicate where the bundles can be found, \
+or try setting the ant property allow.downloads=true to download the bundle from the URL.\
+${line.separator}\
+e.g. ant -Dallow.downloads=true -OR- ant -Ddrops.dir=some_directory \
+${line.separator}
+
+# Failure message when source cannot be downloaded
+failed.url.src.message=\
+ERROR: Cannot find source for project ${ant.project.name}.\
+${line.separator}${line.separator}\
+HINT: Try setting drops.dir to indicate where the bundles can be found, \
+or try checking the URL with your browser.\
+${line.separator}\
+e.g. ant -Ddrops.dir=some_directory \
+${line.separator}
+
 #------------------------------------------------------------

--- a/build.xml	Thu Jun 17 10:43:17 2010 -0700
+++ b/build.xml	Thu Jun 17 10:50:14 2010 -0700
@@ -36,6 +36,11 @@
       javac.debug          - true or false for debug classfiles
       javac.target         - classfile version target
       javac.source         - source version
+      drops.dir            - directory that holds source drop bundles
+      allow.download       - permit downloads from public url (default is false)
+                             (used if bundles not found in drops.dir)
+
+      Run 'make help' for help using the Makefile.
     </description>
 
     <!-- Mac is special, need to downgrade these before build.properties. -->
@@ -106,16 +111,20 @@
         <jar file="${dist.classes.jar}" basedir="${build.classes.dir}"/>
     </target>
 
-    <target name="-build-prep"
-	    depends="init, -init-src-dirs, -drop-build-prep">
+    <target name="-build-setup"
+	    depends="init, -init-src-dirs, -drop-build-setup">
     </target>
 
     <!-- Build (compilation) of sources to class files. -->
     <target name="build"
-	    depends="init, -init-src-dirs, -build-prep">
+	    depends="compile, -build-setup">
+    </target>
+    <target name="compile"
+	    depends="init, -init-src-dirs">
+        <mkdir dir="${build.classes.dir}"/>
         <javac 
-	     includeAntRuntime="false"
-	     classpath="${build.classes.dir}"
+	     includeAntRuntime="false" 
+	     classpath="${build.classes.dir}:${tools.jar}"
 	     fork="true"
              destdir="${build.classes.dir}"
              memoryInitialSize="${javac.memoryInitialSize}"

--- a/make/Makefile	Thu Jun 17 10:43:17 2010 -0700
+++ b/make/Makefile	Thu Jun 17 10:50:14 2010 -0700
@@ -65,6 +65,11 @@
   endif
 endif 
 
+# If downloads are allowed
+ifeq ($(ALLOW_DOWNLOADS),true)
+  ANT_OPTIONS += -Dallow.downloads=true
+endif
+
 # Figure out the platform we are using
 _SYSTEM_UNAME := $(shell uname)
 _PLATFORM_KIND = unix
@@ -159,6 +164,8 @@
 	@echo "    $(ANT_TARGETS)"
 	@echo " "
 	@echo "  Environment or command line variables (all optional):"
+	$(call helpenvline, ALT_DROPS_DIR,\
+	       "Directory that contains the drop source bundles i.e. drops.dir")
 	$(call helpenvline, ALT_BOOTDIR,\
 	       "JAVA_HOME to use when running ant")
 	$(call helpenvline, ALT_LANGTOOLS_DIST,\