#27: Format version identifier in execution data encoding

1 files changed, 20 insertions, 2 deletions

diff --git a/org.jacoco.core/src/org/jacoco/core/data/ExecutionDataWriter.java b/org.jacoco.core/src/org/jacoco/core/data/ExecutionDataWriter.java
index f6284ff6..98f0913b 100644
--- a/org.jacoco.core/src/org/jacoco/core/data/ExecutionDataWriter.java
+++ b/org.jacoco.core/src/org/jacoco/core/data/ExecutionDataWriter.java
@@ -27,6 +27,15 @@ import java.io.OutputStream;
  */

 public class ExecutionDataWriter implements IExecutionDataVisitor {

 

+	/** File format version, will be incremented for each incompatible change. */

+	public static final char FORMAT_VERSION = 0x1001;

+

+	/** Block identifier for file headers. */

+	public static final byte BLOCK_HEADER = 0x01;

+

+	/** Block identifier for execution data of a single class. */

+	public static final byte BLOCK_EXECUTIONDATA = 0x10;

+

 	private final DataOutput output;

 

 	/**

@@ -34,9 +43,11 @@ public class ExecutionDataWriter implements IExecutionDataVisitor {
 	 * 

 	 * @param output

 	 *            data output to write execution data to

+	 * @throws IOException

 	 */

-	public ExecutionDataWriter(final DataOutput output) {

+	public ExecutionDataWriter(final DataOutput output) throws IOException {

 		this.output = output;

+		writeHeader();

 	}

 

 	/**

@@ -44,13 +55,20 @@ public class ExecutionDataWriter implements IExecutionDataVisitor {
 	 * 

 	 * @param output

 	 *            binary stream to write execution data to

+	 * @throws IOException

 	 */

-	public ExecutionDataWriter(final OutputStream output) {

+	public ExecutionDataWriter(final OutputStream output) throws IOException {

 		this((DataOutput) new DataOutputStream(output));

 	}

 

+	private void writeHeader() throws IOException {

+		output.write(BLOCK_HEADER);

+		output.writeChar(FORMAT_VERSION);

+	}

+

 	public void visitClassExecution(final long id, final boolean[][] blockdata) {

 		try {

+			output.write(BLOCK_EXECUTIONDATA);

 			output.writeLong(id);

 			output.writeInt(blockdata.length);

 			for (final boolean[] m : blockdata) {