diff --git a/build/build.xml b/build/build.xml
index fdd1d9a08..bcc3ca42a 100644
--- a/build/build.xml
+++ b/build/build.xml
@@ -388,11 +388,11 @@
           message="Do not call assemble from the command line." />
 
     <!-- copy shared tools folder -->
-    <copy todir="${target.path}/tools">
+    <copy todir="${target.path}/tools" preservelastmodified="true">
       <fileset dir="shared/tools" />
     </copy>
 
-    <copy todir="${target.path}/modes/java">
+    <copy todir="${target.path}/modes/java" preservelastmodified="true">
       <fileset dir="../java">
         <!-- don't include LWJGL, it's not operational -->
         <exclude name="libraries/lwjgl/**" />
@@ -403,7 +403,8 @@
     </copy>
 
     <!-- get the examples folder, but don't require it to buid -->
-    <copy todir="${target.path}/modes/java/examples" failonerror="false">
+    <copy todir="${target.path}/modes/java/examples"
+          preservelastmodified="true" failonerror="false">
       <fileset dir="${examples.dir}" />
     </copy>
 
@@ -643,7 +644,7 @@
       <arg line="${jdk.path.macosx}/Contents/Home/jre/lib/jli/libjli.dylib ${jli.path}"/>
     </exec>
 
-    <copy todir="${contents.dir}/Java">
+    <copy todir="${contents.dir}/Java" preservelastmodified="true">
       <fileset dir=".." includes="core/library/**" /> <!-- why this? -->
       <!--<fileset dir="shared" includes="launch4j/**" />-->
       <fileset dir="shared" includes="lib/**" />
@@ -785,7 +786,7 @@
   <target name="linux-build" depends="ignore-tools, check-linux-arm32, check-linux-arm64, revision-check, linux-check-os, jre-download, subprojects-build, subprojects-build-linux-arm32, subprojects-build-linux-arm64" description="Build Linux version">
     <mkdir dir="linux/work" />
 
-    <copy todir="linux/work">
+    <copy todir="linux/work" preservelastmodified="true">
       <fileset dir=".." includes="core/library/**" />
       <fileset dir="shared" includes="launch4j/**" />
       <fileset dir="shared" includes="lib/**"  />
@@ -818,7 +819,7 @@
       <fileset dir="${launch4j.dir}/bin" includes="windres-*" />
     </delete>
 
-    <copy todir="linux/work/lib" flatten="true">
+    <copy todir="linux/work/lib" flatten="true" preservelastmodified="true">
       <fileset refid="runtime.jars" />
     </copy>
 
@@ -1073,7 +1074,7 @@
 
     <!-- assemble the pde -->
     <mkdir dir="windows/work/lib" />
-    <copy todir="windows/work/lib" flatten="true">
+    <copy todir="windows/work/lib" flatten="true" preservelastmodified="true">
       <fileset refid="runtime.jars" />
     </copy>
 
@@ -1094,7 +1095,7 @@
       <mapper type="flatten"/>
     </unzip>
 
-    <copy todir="windows/work">
+    <copy todir="windows/work" preservelastmodified="true">
       <fileset dir=".." includes="core/library/**" />
       <fileset dir="shared" includes="launch4j/**" />
       <fileset dir="shared" includes="lib/**" />
diff --git a/core/build.xml b/core/build.xml
index 0b82eba67..e1bf0fd5f 100644
--- a/core/build.xml
+++ b/core/build.xml
@@ -15,20 +15,20 @@
   </target>
 
   <target name="compile" description="Compile" depends="methods-build">
-    <taskdef name="methods" 
-	     classname="PAppletMethods" 
+    <taskdef name="methods"
+	     classname="PAppletMethods"
 	     classpath="methods/methods.jar" />
     <methods dir="${basedir}/src/processing/core" recorder="true" />
 
     <!-- Where can I expect to find Java Mode JARs? -->
     <property name="java.mode" value="../java/mode/" />
-        
+
     <!-- Check for JDT compiler, since this is likely a PDE build. Using
 	 it allows us to build the PDE with only a JRE on Windows and Linux.
-	 So that the core can be built independently of the PDE, 
+	 So that the core can be built independently of the PDE,
 	 use javac (the "modern" compiler) if ecj is not present. -->
     <property name="jdt.jar" value="${java.mode}/org.eclipse.jdt.core.jar" />
-    <condition property="build.compiler" 
+    <condition property="build.compiler"
 	       value="org.eclipse.jdt.core.JDTCompilerAdapter"
 	       else="modern">
       <available file="${jdt.jar}" />
@@ -51,8 +51,8 @@
 	   includeAntRuntime="false"
 	   debug="true"
 	   destdir="bin"
-	   classpath="apple.jar; 
-                      library/jogl-all.jar; 
+	   classpath="apple.jar;
+                      library/jogl-all.jar;
                       library/gluegen-rt.jar"
 	   nowarn="true">
       <!-- kinda gross, but if not using the JDT, this just ignored anyway -->
@@ -61,23 +61,24 @@
       <include name="processing/**" />
       <exclude name="processing/javafx/**" if="fx.unavailable" />
     </javac>
-    
+
     <!-- Copy the jnilib to the bin folder so it's included. -->
-    <copy todir="bin/japplemenubar" 
-	  file="src/japplemenubar/libjAppleMenuBar.jnilib" />
+    <copy todir="bin/japplemenubar"
+	        file="src/japplemenubar/libjAppleMenuBar.jnilib"
+          preservelastmodified="true" />
 
     <!-- Copy shaders to bin. (Eclipse does this automatically.) -->
-    <copy todir="bin">
+    <copy todir="bin" preservelastmodified="true">
       <fileset dir="src">
         <include name="processing/opengl/shaders/*.glsl" />
         <include name="processing/opengl/cursors/*.png" />
         <include name="icon/*.png" />
       </fileset>
     </copy>
-  </target>		
+  </target>
 
   <target name="build" depends="compile" description="Build core library">
     <jar basedir="bin" destfile="library/core.jar" />
   </target>
-  
+
 </project>
diff --git a/java/build.xml b/java/build.xml
index 32932744b..0fda9c2c5 100644
--- a/java/build.xml
+++ b/java/build.xml
@@ -1,15 +1,15 @@
 <?xml version="1.0"?>
 <project name="Java Mode" default="build">
 
-  <property name="generated" 
-	    value="${basedir}/generated/processing/mode/java/preproc" />
+  <property name="generated"
+	          value="${basedir}/generated/processing/mode/java/preproc" />
   <mkdir dir="${generated}" />
 
-  <property name="grammars" 
-	    value="${basedir}/src/processing/mode/java/preproc" />
+  <property name="grammars"
+	          value="${basedir}/src/processing/mode/java/preproc" />
 
-  <property name="antlr_jar" 
-	    value="${basedir}/mode/antlr.jar" />
+  <property name="antlr_jar"
+	          value="${basedir}/mode/antlr.jar" />
 
   <property name="mode_jar"
             value="${basedir}/mode/JavaMode.jar" />
@@ -23,12 +23,12 @@
     <delete file="${mode_jar}" />
     <delete>
       <fileset dir="${generated}">
-	<include name="*.java" />
-	<include name="*.tokens" />
-	<include name="*.txt" />
-	<include name="*.g" />
-	<include name="*.smap" />
-	<include name="*.properties" />
+      	<include name="*.java" />
+      	<include name="*.tokens" />
+      	<include name="*.txt" />
+      	<include name="*.g" />
+      	<include name="*.smap" />
+      	<include name="*.properties" />
       </fileset>
     </delete>
   </target>
@@ -37,9 +37,9 @@
     <antlr target="${grammars}/java15.g" outputdirectory="${generated}">
       <classpath path="${antlr_jar}" />
     </antlr>
-    <antlr target="${grammars}/pde.g" 
-	   outputdirectory="${generated}" 
-	   glib="${grammars}/java15.g">
+    <antlr target="${grammars}/pde.g"
+	         outputdirectory="${generated}"
+	         glib="${grammars}/java15.g">
       <classpath path="${antlr_jar}" />
     </antlr>
 
@@ -49,28 +49,24 @@
     <property name="uc" value="@SuppressWarnings({ &quot;unused&quot;, &quot;cast&quot; })${line.separator}" />
 
     <!-- need to match against the previous line so that we don't re-add -->
-    <replaceregexp 
-        file="generated/processing/mode/java/preproc/JavaLexer.java"
-        match="(\n\n)(public class JavaLexer .*)" 
-        replace="\1${uucr}\2">
+    <replaceregexp file="generated/processing/mode/java/preproc/JavaLexer.java"
+                   match="(\n\n)(public class JavaLexer .*)"
+                   replace="\1${uucr}\2">
     </replaceregexp>
 
-    <replaceregexp 
-        file="generated/processing/mode/java/preproc/JavaRecognizer.java"
-        match="(\*/\n)(public class JavaRecognizer .*)" 
-        replace="\1${uc}\2">
+    <replaceregexp file="generated/processing/mode/java/preproc/JavaRecognizer.java"
+                   match="(\*/\n)(public class JavaRecognizer .*)"
+                   replace="\1${uc}\2">
     </replaceregexp>
 
-    <replaceregexp 
-        file="generated/processing/mode/java/preproc/PdeLexer.java"
-        match="(\n\n)(public class PdeLexer .*)" 
-        replace="\1${uucr}\2">
+    <replaceregexp file="generated/processing/mode/java/preproc/PdeLexer.java"
+                   match="(\n\n)(public class PdeLexer .*)"
+                   replace="\1${uucr}\2">
     </replaceregexp>
 
-    <replaceregexp 
-        file="generated/processing/mode/java/preproc/PdeRecognizer.java"
-        match="(\n\n)(public class PdeRecognizer .*)" 
-        replace="\1${uc}\2">
+    <replaceregexp file="generated/processing/mode/java/preproc/PdeRecognizer.java"
+                   match="(\n\n)(public class PdeRecognizer .*)"
+                   replace="\1${uc}\2">
     </replaceregexp>
     <!-- end of workaround for old antlr -->
   </target>
@@ -86,38 +82,37 @@
     </condition>
     <fail unless="app-built" message="Please build app first and make sure it is located at ../app/pde.jar" />
 
-
     <mkdir dir="bin" />
-       
+
     <!-- in some cases, pde.jar was not getting built
-	 https://github.com/processing/processing/issues/1792 -->
+	       https://github.com/processing/processing/issues/1792 -->
     <delete file="${mode_jar}" />
 
     <!-- env used to set classpath below -->
     <property environment="env" />
 
     <javac source="1.8"
-	   target="1.8"
-	   destdir="bin" 
-	   excludes="**/tools/format/**" 
-	   encoding="UTF-8" 
-	   includeAntRuntime="false" 
-	   classpath="../core/library/core.jar; 
+      	   target="1.8"
+      	   destdir="bin"
+      	   excludes="**/tools/format/**"
+      	   encoding="UTF-8"
+      	   includeAntRuntime="false"
+      	   classpath="../core/library/core.jar;
 
                       ../app/pde.jar;
-                      ../app/lib/ant.jar; 
-                      ../app/lib/ant-launcher.jar; 
-                      ../app/lib/apple.jar; 
-                      ../app/lib/jna.jar; 
-                      ../app/lib/jna-platform.jar; 
+                      ../app/lib/ant.jar;
+                      ../app/lib/ant-launcher.jar;
+                      ../app/lib/apple.jar;
+                      ../app/lib/jna.jar;
+                      ../app/lib/jna-platform.jar;
 
-                      mode/antlr.jar; 
-                      mode/classpath-explorer-1.0.jar; 
+                      mode/antlr.jar;
+                      mode/classpath-explorer-1.0.jar;
                       mode/jsoup-1.7.1.jar;
-                      mode/org.netbeans.swing.outline.jar; 
+                      mode/org.netbeans.swing.outline.jar;
 
-                      mode/jdi.jar; 
-                      mode/jdimodel.jar; 
+                      mode/jdi.jar;
+                      mode/jdimodel.jar;
 
                       mode/com.ibm.icu.jar;
 
@@ -130,12 +125,12 @@
                       mode/org.eclipse.jdt.core.jar;
                       mode/org.eclipse.osgi.jar;
                       mode/org.eclipse.text.jar"
-	   debug="on"
-	   nowarn="true"
-	   compiler="org.eclipse.jdt.core.JDTCompilerAdapter">
+      	   debug="on"
+      	   nowarn="true"
+      	   compiler="org.eclipse.jdt.core.JDTCompilerAdapter">
       <src path="src" />
       <src path="generated" />
-      <compilerclasspath path="mode/org.eclipse.jdt.core.jar; 
+      <compilerclasspath path="mode/org.eclipse.jdt.core.jar;
                                mode/jdtCompilerAdapter.jar" />
     </javac>
   </target>