diff --git a/WHATSNEW b/WHATSNEW
index d191f9fdb..ce969f403 100644
--- a/WHATSNEW
+++ b/WHATSNEW
@@ -75,6 +75,9 @@ Other changes:
 
  * added "javac10+" as new supported value for javac's compiler attribute.
 
+ * javah has been removed from Java 10. The task will now throw an
+   exception if you try to use it while running Java 10 or newer.
+
 Changes from Ant 1.10.0 TO Ant 1.10.1
 =====================================
 
diff --git a/manual/Tasks/javah.html b/manual/Tasks/javah.html
index bc49d77da..088b6e85d 100644
--- a/manual/Tasks/javah.html
+++ b/manual/Tasks/javah.html
@@ -39,7 +39,8 @@ systems are used.</p>
   generate the native header files with a single step.</p>
 
 <p><b>Note</b> the <code>javah</code> has been deprecated as of Java 9
-  and is scheduled to be removed with Java 10.</p>
+  and removed as of Java 10. Trying to use it with Java10 will
+  fail.</p>
 
 <p>It is possible to use different compilers. This can be selected
 with the <code>implementation</code> attribute or a nested element.  <a
diff --git a/src/main/org/apache/tools/ant/taskdefs/optional/javah/JavahAdapterFactory.java b/src/main/org/apache/tools/ant/taskdefs/optional/javah/JavahAdapterFactory.java
index 2244e5b26..931131b6b 100644
--- a/src/main/org/apache/tools/ant/taskdefs/optional/javah/JavahAdapterFactory.java
+++ b/src/main/org/apache/tools/ant/taskdefs/optional/javah/JavahAdapterFactory.java
@@ -90,6 +90,11 @@ public class JavahAdapterFactory {
             || Gcjh.IMPLEMENTATION_NAME.equals(choice)) {
             return new Gcjh();
         }
+        if (JavaEnvUtils.isAtLeastJavaVersion("10") &&
+            (choice == null || ForkingJavah.IMPLEMENTATION_NAME.equals(choice))) {
+            throw new BuildException("javah does not exist under Java 10 and higher,"
+                + " use the javac task with nativeHeaderDir instead");
+        }
         if (ForkingJavah.IMPLEMENTATION_NAME.equals(choice)) {
             return new ForkingJavah();
         }
diff --git a/src/main/org/apache/tools/ant/util/JavaEnvUtils.java b/src/main/org/apache/tools/ant/util/JavaEnvUtils.java
index 735675dac..e8e01ea81 100644
--- a/src/main/org/apache/tools/ant/util/JavaEnvUtils.java
+++ b/src/main/org/apache/tools/ant/util/JavaEnvUtils.java
@@ -187,8 +187,12 @@ public final class JavaEnvUtils {
             javaVersionNumber = VERSION_9;
             // at least Java9 and this should properly support the purely numeric version property
             String v = System.getProperty("java.specification.version");
-            javaVersionNumber = Integer.parseInt(v) * 10;
-            javaVersion = v;
+            DeweyDecimal pv = new DeweyDecimal(v);
+            javaVersionNumber = pv.get(0) * 10;
+            if (pv.getSize() > 1) {
+                javaVersionNumber += pv.get(1);
+            }
+            javaVersion = pv.toString();
         } catch (Throwable t) {
             // swallow as we've hit the max class version that
             // we have
diff --git a/src/tests/antunit/taskdefs/optional/javah-test.xml b/src/tests/antunit/taskdefs/optional/javah-test.xml
index 884523d9f..82d91c8f6 100644
--- a/src/tests/antunit/taskdefs/optional/javah-test.xml
+++ b/src/tests/antunit/taskdefs/optional/javah-test.xml
@@ -101,12 +101,12 @@ public class Foo {
     </presetdef>
   </target>
 
-  <target name="testSimpleCompile" depends="-setupForRealJavahTests">
+  <target name="testSimpleCompile" depends="-setupForRealJavahTests" unless="jdk10+">
     <javah-single/>
     <au:assertFileExists file="${output}/org_example_Foo.h"/>
   </target>
 
-  <target name="testCompileUsingFileset" depends="-setupForRealJavahTests">
+  <target name="testCompileUsingFileset" depends="-setupForRealJavahTests" unless="jdk10+">
     <javah-fileset/>
     <au:assertFileExists file="${output}/org_example_Foo.h"/>
   </target>
@@ -123,13 +123,21 @@ public class Foo {
     <au:assertFileExists file="${output}/org_example_Foo.h"/>
   </target>
 
-  <target name="testSimpleCompileForking" depends="-setupForRealJavahTests">
+  <target name="testSimpleCompileForking" depends="-setupForRealJavahTests" unless="jdk10+">
     <javah-single implementation="forking"/>
     <au:assertFileExists file="${output}/org_example_Foo.h"/>
   </target>
 
-  <target name="testCompileUsingFilesetForking" depends="-setupForRealJavahTests">
+  <target name="testCompileUsingFilesetForking" depends="-setupForRealJavahTests" unless="jdk10+">
     <javah-fileset implementation="forking"/>
     <au:assertFileExists file="${output}/org_example_Foo.h"/>
   </target>
+
+  <target name="testSimpleCompileFailsOnJava10+" depends="-setupForRealJavahTests"
+          if="jdk10+">
+    <au:expectfailure>
+      <javah-single/>
+    </au:expectfailure>
+  </target>
+
 </project>
diff --git a/src/tests/junit/org/apache/tools/ant/taskdefs/optional/JavahTest.java b/src/tests/junit/org/apache/tools/ant/taskdefs/optional/JavahTest.java
index 40472de2b..91f7b3278 100644
--- a/src/tests/junit/org/apache/tools/ant/taskdefs/optional/JavahTest.java
+++ b/src/tests/junit/org/apache/tools/ant/taskdefs/optional/JavahTest.java
@@ -18,6 +18,8 @@
 package org.apache.tools.ant.taskdefs.optional;
 
 import org.apache.tools.ant.BuildFileRule;
+import org.apache.tools.ant.util.JavaEnvUtils;
+import org.junit.Assume;
 import org.junit.After;
 import org.junit.Before;
 import org.junit.Rule;
@@ -47,6 +49,7 @@ public class JavahTest {
 
     @Test
     public void testSimpleCompile() {
+        Assume.assumeFalse(JavaEnvUtils.isAtLeastJavaVersion("10"));
         buildRule.executeTarget("simple-compile");
         assertTrue(new File(buildRule.getProject().getProperty("output"), "org_example_Foo.h")
                 .exists());
@@ -54,6 +57,7 @@ public class JavahTest {
 
     @Test
     public void testCompileFileset() {
+        Assume.assumeFalse(JavaEnvUtils.isAtLeastJavaVersion("10"));
         buildRule.executeTarget("test-fileset");
         assertTrue(new File(buildRule.getProject().getProperty("output"), "org_example_Foo.h").exists());
     }
diff --git a/src/tests/junit/org/apache/tools/ant/util/JavaEnvUtilsTest.java b/src/tests/junit/org/apache/tools/ant/util/JavaEnvUtilsTest.java
index 28e1386cb..57d45e56b 100644
--- a/src/tests/junit/org/apache/tools/ant/util/JavaEnvUtilsTest.java
+++ b/src/tests/junit/org/apache/tools/ant/util/JavaEnvUtilsTest.java
@@ -143,4 +143,15 @@ public class JavaEnvUtilsTest {
         assertTrue("JAVA_1_9 is not considered equal to JAVA_9",
                 JavaEnvUtils.isJavaVersion(JavaEnvUtils.JAVA_1_9));
     }
+
+    @Test
+    public void java10IsDetectedProperly() {
+        assumeTrue("10".equals(System.getProperty("java.specification.version")));
+        assertEquals("10", JavaEnvUtils.getJavaVersion());
+        assertEquals(100, JavaEnvUtils.getJavaVersionNumber());
+        assertEquals(new DeweyDecimal("10"), JavaEnvUtils.getParsedJavaVersion());
+        assertTrue(JavaEnvUtils.isJavaVersion("10"));
+        assertTrue(JavaEnvUtils.isAtLeastJavaVersion(JavaEnvUtils.JAVA_9));
+    }
+
 }