Trac #150: Allow empty exec files.

1 files changed, 13 insertions, 9 deletions

diff --git a/org.jacoco.core/src/org/jacoco/core/data/ExecutionDataReader.java b/org.jacoco.core/src/org/jacoco/core/data/ExecutionDataReader.java
index b4dccaee..4afbc905 100644
--- a/org.jacoco.core/src/org/jacoco/core/data/ExecutionDataReader.java
+++ b/org.jacoco.core/src/org/jacoco/core/data/ExecutionDataReader.java
@@ -27,9 +27,11 @@ public class ExecutionDataReader {
 	/** Underlying data input */

 	protected final CompactDataInput in;

 

-	private ISessionInfoVisitor sessionInfoVisitor;

+	private ISessionInfoVisitor sessionInfoVisitor = null;

 

-	private IExecutionDataVisitor executionDataVisitor;

+	private IExecutionDataVisitor executionDataVisitor = null;

+

+	private boolean firstBlock = true;

 

 	/**

 	 * Creates a new reader based on the given input stream input. Depending on

@@ -38,13 +40,9 @@ public class ExecutionDataReader {
 	 * 

 	 * @param input

 	 *            input stream to read execution data from

-	 * @throws IOException

-	 *             if the stream does not have a valid header

 	 */

-	public ExecutionDataReader(final InputStream input) throws IOException {

+	public ExecutionDataReader(final InputStream input) {

 		this.in = new CompactDataInput(input);

-		in.readByte();

-		readHeader();

 	}

 

 	/**

@@ -77,8 +75,14 @@ public class ExecutionDataReader {
 	 */

 	public boolean read() throws IOException {

 		try {

-			while (readBlock(in.readByte())) {

-			}

+			byte type;

+			do {

+				type = in.readByte();

+				if (firstBlock && type != ExecutionDataWriter.BLOCK_HEADER) {

+					throw new IOException("Invalid execution data file.");

+				}

+				firstBlock = false;

+			} while (readBlock(type));

 			return true;

 		} catch (final EOFException e) {

 			return false;