Add experimental support for Java 13 class files (#835)

2 files changed, 24 insertions, 0 deletions

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 1d7617ee..74574ecc 100644
--- a/org.jacoco.core/src/org/jacoco/core/internal/ContentTypeDetector.java
+++ b/org.jacoco.core/src/org/jacoco/core/internal/ContentTypeDetector.java
@@ -88,6 +88,8 @@ public class ContentTypeDetector {
 			case Opcodes.V11 | Opcodes.V_PREVIEW:
 			case Opcodes.V12:
 			case Opcodes.V12 | Opcodes.V_PREVIEW:
+			case (Opcodes.V12 + 1):
+			case (Opcodes.V12 + 1) | Opcodes.V_PREVIEW:
 				return CLASSFILE;
 			}
 		}
diff --git a/org.jacoco.core/src/org/jacoco/core/internal/instr/InstrSupport.java b/org.jacoco.core/src/org/jacoco/core/internal/instr/InstrSupport.java
index ce4bcbee..99e00270 100644
--- a/org.jacoco.core/src/org/jacoco/core/internal/instr/InstrSupport.java
+++ b/org.jacoco.core/src/org/jacoco/core/internal/instr/InstrSupport.java
@@ -13,6 +13,7 @@ package org.jacoco.core.internal.instr;
 
 import static java.lang.String.format;
 
+import org.objectweb.asm.ClassReader;
 import org.objectweb.asm.MethodVisitor;
 import org.objectweb.asm.Opcodes;
 
@@ -227,4 +228,25 @@ public final class InstrSupport {
 		}
 	}
 
+	/**
+	 * Creates a {@link ClassReader} instance for given bytes of class even if
+	 * its version not yet supported by ASM.
+	 *
+	 * @param b
+	 *            bytes of class
+	 * @return {@link ClassReader}
+	 */
+	public static ClassReader classReaderFor(final byte[] b) {
+		final byte[] originalVersion = new byte[] { b[4], b[5], b[6], b[7] };
+		if (getVersionMajor(b) == Opcodes.V12 + 1) {
+			b[4] = (byte) (Opcodes.V12 >>> 24);
+			b[5] = (byte) (Opcodes.V12 >>> 16);
+			b[6] = (byte) (Opcodes.V12 >>> 8);
+			b[7] = (byte) Opcodes.V12;
+		}
+		final ClassReader classReader = new ClassReader(b);
+		System.arraycopy(originalVersion, 0, b, 4, originalVersion.length);
+		return classReader;
+	}
+
 }