diff --git a/jacoco-maven-plugin.test/it/it-java9/invoker.properties b/jacoco-maven-plugin.test/it/it-java9/invoker.properties
new file mode 100644
index 0000000..750530b
--- /dev/null
+++ b/jacoco-maven-plugin.test/it/it-java9/invoker.properties
@@ -0,0 +1 @@
+invoker.java.version = 1.9+
diff --git a/jacoco-maven-plugin.test/it/it-java9/pom.xml b/jacoco-maven-plugin.test/it/it-java9/pom.xml
new file mode 100644
index 0000000..37b70d9
--- /dev/null
+++ b/jacoco-maven-plugin.test/it/it-java9/pom.xml
@@ -0,0 +1,70 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+   Copyright (c) 2009, 2016 Mountainminds GmbH & Co. KG and Contributors
+   All rights reserved. This program and the accompanying materials
+   are made available under the terms of the Eclipse Public License v1.0
+   which accompanies this distribution, and is available at
+   http://www.eclipse.org/legal/epl-v10.html
+
+   Contributors:
+      Evgeny Mandrikov - initial API and implementation
+-->
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+
+  <parent>
+    <groupId>jacoco</groupId>
+    <artifactId>setup-parent</artifactId>
+    <version>1.0-SNAPSHOT</version>
+    <relativePath>../setup-parent</relativePath>
+  </parent>
+
+  <artifactId>it-java9</artifactId>
+
+  <build>
+    <plugins>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-compiler-plugin</artifactId>
+        <configuration>
+          <target>1.9</target>
+        </configuration>
+      </plugin>
+      <plugin>
+        <groupId>@project.groupId@</groupId>
+        <artifactId>jacoco-maven-plugin</artifactId>
+        <executions>
+          <execution>
+            <goals>
+              <goal>prepare-agent</goal>
+              <goal>report</goal>
+            </goals>
+          </execution>
+          <execution>
+            <id>check</id>
+            <goals>
+              <goal>check</goal>
+            </goals>
+            <configuration>
+              <rules>
+                <!-- implementation is needed only for Maven 2 -->
+                <rule implementation="org.jacoco.maven.RuleConfiguration">
+                  <limits>
+                    <!-- implementation is needed only for Maven 2 -->
+                    <limit implementation="org.jacoco.report.check.Limit">
+                      <counter>INSTRUCTION</counter>
+                      <value>COVEREDCOUNT</value>
+                      <minimum>8</minimum>
+                      <maximum>8</maximum>
+                    </limit>
+                  </limits>
+                </rule>
+              </rules>
+            </configuration>
+          </execution>
+        </executions>
+      </plugin>
+    </plugins>
+  </build>
+</project>
diff --git a/jacoco-maven-plugin.test/it/it-java9/src/main/java/Example.java b/jacoco-maven-plugin.test/it/it-java9/src/main/java/Example.java
new file mode 100644
index 0000000..2f24b3c
--- /dev/null
+++ b/jacoco-maven-plugin.test/it/it-java9/src/main/java/Example.java
@@ -0,0 +1,19 @@
+/*******************************************************************************
+ * Copyright (c) 2009, 2016 Mountainminds GmbH & Co. KG and Contributors
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *    Evgeny Mandrikov - initial API and implementation
+ *
+ *******************************************************************************/
+public class Example {
+
+  public void sayHello(String name) {
+    // http://openjdk.java.net/jeps/280
+    System.out.println("Hello, " + name);
+  }
+
+}
diff --git a/jacoco-maven-plugin.test/it/it-java9/src/test/java/ExampleTest.java b/jacoco-maven-plugin.test/it/it-java9/src/test/java/ExampleTest.java
new file mode 100644
index 0000000..f89af13
--- /dev/null
+++ b/jacoco-maven-plugin.test/it/it-java9/src/test/java/ExampleTest.java
@@ -0,0 +1,21 @@
+/*******************************************************************************
+ * Copyright (c) 2009, 2016 Mountainminds GmbH & Co. KG and Contributors
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *    Evgeny Mandrikov - initial API and implementation
+ *
+ *******************************************************************************/
+import org.junit.Test;
+
+public class ExampleTest {
+
+  @Test
+  public void test() {
+    new Example().sayHello("test");
+  }
+
+}
diff --git a/org.jacoco.core.test/src/org/jacoco/core/internal/ContentTypeDetectorTest.java b/org.jacoco.core.test/src/org/jacoco/core/internal/ContentTypeDetectorTest.java
index 09b653b..b6f272c 100644
--- a/org.jacoco.core.test/src/org/jacoco/core/internal/ContentTypeDetectorTest.java
+++ b/org.jacoco.core.test/src/org/jacoco/core/internal/ContentTypeDetectorTest.java
@@ -108,6 +108,13 @@
 	}
 
 	@Test
+	public void testClassFile19() throws IOException {
+		initData(0xCA, 0xFE, 0xBA, 0xBE, 0x00, 0x00, 0x00, 0x35);
+		assertEquals(ContentTypeDetector.CLASSFILE, detector.getType());
+		assertContent();
+	}
+
+	@Test
 	public void testMachObjectFile() throws IOException {
 		initData(0xCA, 0xFE, 0xBA, 0xBE, 0x00, 0x00, 0x00, 0x02);
 		assertEquals(ContentTypeDetector.UNKNOWN, detector.getType());
diff --git a/org.jacoco.core.test/src/org/jacoco/core/test/validation/ClassFileVersionsTest.java b/org.jacoco.core.test/src/org/jacoco/core/test/validation/ClassFileVersionsTest.java
index 08f66f8..c51a58a 100644
--- a/org.jacoco.core.test/src/org/jacoco/core/test/validation/ClassFileVersionsTest.java
+++ b/org.jacoco.core.test/src/org/jacoco/core/test/validation/ClassFileVersionsTest.java
@@ -30,6 +30,7 @@
 
 import org.jacoco.core.JaCoCo;
 import org.jacoco.core.instr.Instrumenter;
+import org.jacoco.core.internal.Java9Support;
 import org.jacoco.core.runtime.IRuntime;
 import org.jacoco.core.runtime.SystemPropertiesRuntime;
 import org.junit.Test;
@@ -83,6 +84,11 @@
 		testVersion(V1_8, true);
 	}
 
+	@Test
+	public void test_1_9() throws IOException {
+		testVersion(Java9Support.V1_9, true);
+	}
+
 	private void testVersion(int version, boolean frames) throws IOException {
 		final byte[] original = createClass(version);
 
@@ -95,7 +101,7 @@
 
 	private void assertFrames(byte[] source, boolean expected) {
 		final boolean[] hasFrames = new boolean[] { false };
-		new ClassReader(source).accept(
+		new ClassReader(Java9Support.downgradeIfRequired(source)).accept(
 				new ClassVisitor(JaCoCo.ASM_API_VERSION) {
 
 					@Override
diff --git a/org.jacoco.core/src/org/jacoco/core/analysis/Analyzer.java b/org.jacoco.core/src/org/jacoco/core/analysis/Analyzer.java
index ac86128..7ab9003 100644
--- a/org.jacoco.core/src/org/jacoco/core/analysis/Analyzer.java
+++ b/org.jacoco.core/src/org/jacoco/core/analysis/Analyzer.java
@@ -23,6 +23,7 @@
 import org.jacoco.core.data.ExecutionData;
 import org.jacoco.core.data.ExecutionDataStore;
 import org.jacoco.core.internal.ContentTypeDetector;
+import org.jacoco.core.internal.Java9Support;
 import org.jacoco.core.internal.Pack200Streams;
 import org.jacoco.core.internal.analysis.ClassAnalyzer;
 import org.jacoco.core.internal.analysis.ClassCoverageImpl;
@@ -123,7 +124,8 @@
 	public void analyzeClass(final byte[] buffer, final String location)
 			throws IOException {
 		try {
-			analyzeClass(new ClassReader(buffer));
+			analyzeClass(
+					new ClassReader(Java9Support.downgradeIfRequired(buffer)));
 		} catch (final RuntimeException cause) {
 			throw analyzerError(location, cause);
 		}
@@ -142,7 +144,7 @@
 	public void analyzeClass(final InputStream input, final String location)
 			throws IOException {
 		try {
-			analyzeClass(new ClassReader(input));
+			analyzeClass(Java9Support.readFully(input), location);
 		} catch (final RuntimeException e) {
 			throw analyzerError(location, e);
 		}
diff --git a/org.jacoco.core/src/org/jacoco/core/instr/Instrumenter.java b/org.jacoco.core/src/org/jacoco/core/instr/Instrumenter.java
index 0d4eea6..5a0ce7a 100644
--- a/org.jacoco.core/src/org/jacoco/core/instr/Instrumenter.java
+++ b/org.jacoco.core/src/org/jacoco/core/instr/Instrumenter.java
@@ -22,6 +22,7 @@
 import java.util.zip.ZipOutputStream;
 
 import org.jacoco.core.internal.ContentTypeDetector;
+import org.jacoco.core.internal.Java9Support;
 import org.jacoco.core.internal.Pack200Streams;
 import org.jacoco.core.internal.flow.ClassProbesAdapter;
 import org.jacoco.core.internal.instr.ClassInstrumenter;
@@ -98,7 +99,14 @@
 	public byte[] instrument(final byte[] buffer, final String name)
 			throws IOException {
 		try {
-			return instrument(new ClassReader(buffer));
+			if (Java9Support.isPatchRequired(buffer)) {
+				final byte[] result = instrument(
+						new ClassReader(Java9Support.downgrade(buffer)));
+				Java9Support.upgrade(result);
+				return result;
+			} else {
+				return instrument(new ClassReader(buffer));
+			}
 		} catch (final RuntimeException e) {
 			throw instrumentError(name, e);
 		}
@@ -119,7 +127,7 @@
 	public byte[] instrument(final InputStream input, final String name)
 			throws IOException {
 		try {
-			return instrument(new ClassReader(input));
+			return instrument(Java9Support.readFully(input), name);
 		} catch (final RuntimeException e) {
 			throw instrumentError(name, e);
 		}
@@ -141,7 +149,7 @@
 	public void instrument(final InputStream input, final OutputStream output,
 			final String name) throws IOException {
 		try {
-			output.write(instrument(new ClassReader(input)));
+			output.write(instrument(Java9Support.readFully(input), name));
 		} catch (final RuntimeException e) {
 			throw instrumentError(name, e);
 		}
diff --git a/org.jacoco.core/src/org/jacoco/core/internal/ContentTypeDetector.java b/org.jacoco.core/src/org/jacoco/core/internal/ContentTypeDetector.java
index 5bd22a4..7f734c1 100644
--- a/org.jacoco.core/src/org/jacoco/core/internal/ContentTypeDetector.java
+++ b/org.jacoco.core/src/org/jacoco/core/internal/ContentTypeDetector.java
@@ -82,6 +82,7 @@
 			case Opcodes.V1_6:
 			case Opcodes.V1_7:
 			case Opcodes.V1_8:
+			case Java9Support.V1_9:
 				return CLASSFILE;
 			}
 		}
diff --git a/org.jacoco.core/src/org/jacoco/core/internal/Java9Support.java b/org.jacoco.core/src/org/jacoco/core/internal/Java9Support.java
new file mode 100644
index 0000000..fae1e0e
--- /dev/null
+++ b/org.jacoco.core/src/org/jacoco/core/internal/Java9Support.java
@@ -0,0 +1,115 @@
+/*******************************************************************************
+ * Copyright (c) 2009, 2016 Mountainminds GmbH & Co. KG and Contributors
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *    Evgeny Mandrikov - initial API and implementation
+ *
+ *******************************************************************************/
+package org.jacoco.core.internal;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+
+import org.objectweb.asm.Opcodes;
+
+/**
+ * Patching for Java 9 classes, so that ASM can read them.
+ */
+public final class Java9Support {
+
+	/**
+	 * Version of the Java 9 class file format.
+	 */
+	public static final int V1_9 = Opcodes.V1_8 + 1;
+
+	private Java9Support() {
+	}
+
+	/**
+	 * Reads all bytes from an input stream into a byte array.
+	 *
+	 * @param is
+	 *             the input stream to read from
+	 * @return a byte array containing all the bytes from the stream
+	 * @throws IOException
+	 *             if an I/O error occurs
+	 */
+	public static byte[] readFully(final InputStream is)
+			throws IOException {
+		if (is == null) {
+			throw new IllegalArgumentException();
+		}
+		final byte[] buf = new byte[1024];
+		final ByteArrayOutputStream out = new ByteArrayOutputStream();
+		while (true) {
+			int r = is.read(buf);
+			if (r == -1) {
+				break;
+			}
+			out.write(buf, 0, r);
+		}
+		return out.toByteArray();
+	}
+
+	private static void putShort(byte[] b, int index, int s) {
+		b[index] = (byte) (s >>> 8);
+		b[index + 1] = (byte) s;
+	}
+
+	private static short readShort(byte[] b, int index) {
+		return (short) (((b[index] & 0xFF) << 8) | (b[index + 1] & 0xFF));
+	}
+
+	/**
+	 * Determines whether class definition contains {@link #V1_9} version.
+	 *
+	 * @param buffer
+	 *             definition of the class
+	 * @return <code>true</code> if class definition contains Java 9 version
+	 */
+	public static boolean isPatchRequired(byte[] buffer) {
+		return readShort(buffer, 6) == V1_9;
+	}
+
+	/**
+	 * Returns new definition of class with version {@link Opcodes#V1_8},
+	 * if it has version {@link #V1_9}.
+	 *
+	 * @param buffer
+	 *             definition of the class
+	 * @return new definition of the class
+	 */
+	public static byte[] downgradeIfRequired(byte[] buffer) {
+		return isPatchRequired(buffer) ? downgrade(buffer) : buffer;
+	}
+
+	/**
+	 * Replaces version in the definition of class on {@link Opcodes#V1_8}.
+	 *
+	 * @param b
+	 *             definition of the class
+	 * @return new definition of the class
+	 */
+	public static byte[] downgrade(byte[] b) {
+		byte[] result = new byte[b.length];
+		System.arraycopy(b, 0, result, 0, b.length);
+		putShort(result, 6, Opcodes.V1_8);
+		return result;
+	}
+
+	/**
+	 * Replaces version in the definition of class on {@link #V1_9}.
+	 *
+	 * @param b
+	 *             definition of the class
+	 */
+	public static void upgrade(byte[] b) {
+		putShort(b, 6, V1_9);
+	}
+
+}
diff --git a/org.jacoco.core/src/org/jacoco/core/runtime/ModifiedSystemClassRuntime.java b/org.jacoco.core/src/org/jacoco/core/runtime/ModifiedSystemClassRuntime.java
index 19c6ef9..24e975e 100644
--- a/org.jacoco.core/src/org/jacoco/core/runtime/ModifiedSystemClassRuntime.java
+++ b/org.jacoco.core/src/org/jacoco/core/runtime/ModifiedSystemClassRuntime.java
@@ -20,6 +20,7 @@
 import java.security.ProtectionDomain;
 
 import org.jacoco.core.JaCoCo;
+import org.jacoco.core.internal.Java9Support;
 import org.objectweb.asm.ClassReader;
 import org.objectweb.asm.ClassVisitor;
 import org.objectweb.asm.ClassWriter;
@@ -154,7 +155,7 @@
 	 */
 	public static byte[] instrument(final byte[] source,
 			final String accessFieldName) {
-		final ClassReader reader = new ClassReader(source);
+		final ClassReader reader = new ClassReader(Java9Support.downgradeIfRequired(source));
 		final ClassWriter writer = new ClassWriter(reader, 0);
 		reader.accept(new ClassVisitor(JaCoCo.ASM_API_VERSION, writer) {
 
diff --git a/org.jacoco.doc/docroot/doc/changes.html b/org.jacoco.doc/docroot/doc/changes.html
index 60d4a63..d484dae 100644
--- a/org.jacoco.doc/docroot/doc/changes.html
+++ b/org.jacoco.doc/docroot/doc/changes.html
@@ -30,6 +30,8 @@
   <li>Renamed "dot" resources in generated HTML reports to become more web
       hosting friendly
       (GitHub <a href="https://github.com/jacoco/jacoco/issues/401">#401</a>).</li>
+  <li>Experimental support for Java 9 class files
+      (GitHub <a href="https://github.com/jacoco/jacoco/issues/406">#406</a>).</li>
 </ul>
 
 <h3>Fixed Bugs</h3>