title: JaCoCo SonarQube incompatible version 1007
body: <p>I'm using SonarQube for code quality control and suddenly builds that would otherwise pass can't be analyzed and fails. </p>
  
  <blockquote>
    <p>[INFO] [00:00:03.630] Analysing /mySuperProject/target/jacoco.exec ->
    java.io.IOException: Incompatible version 1007</p>
  </blockquote>
  
  <p>When I invoke maven build with debug switch, this cause is revealed</p>
  
  <pre><code>Caused by: java.io.IOException: Incompatible version 1007.
  at org.jacoco.core.data.ExecutionDataReader.readHeader(ExecutionDataReader.java:127)
  at org.jacoco.core.data.ExecutionDataReader.readBlock(ExecutionDataReader.java:107)
  at org.jacoco.core.data.ExecutionDataReader.read(ExecutionDataReader.java:87)
  at org.sonar.plugins.jacoco.AbstractAnalyzer.readExecutionData(AbstractAnalyzer.java:134)
  at org.sonar.plugins.jacoco.AbstractAnalyzer.analyse(AbstractAnalyzer.java:107)
  </code></pre>
  
  <p>While inspecting jacoco ExecutionDataReader, I found that exception is thrown from </p>
  
  <pre class="lang-java prettyprint-override"><code>if (version != ExecutionDataWriter.FORMAT_VERSION) {
      throw new IOException(format("Incompatible version %x.",Integer.valueOf(version)));
  }
  </code></pre>
  
  <p>and from ExecutionDataWriter I've found out </p>
  
  <pre class="lang-java prettyprint-override"><code>/** File format version, will be incremented for each incompatible change. */
  public static final char FORMAT_VERSION = 0x1007;
  </code></pre>
  
  <p>What is this <strong>incompatible change</strong> and why does it happen?
  Any ideas how to fix this challenge?</p>