title: The type org.jfree.data.general.Series cannot be resolved
body: <p>I have been updating my development environment to Eclipse Neon and introducing m2e to manage project dependencies. in one project the original (very old) versions of <code>JFreeChart</code> were not available on maven so I have put in the latest versions of <code>JFreeChart</code> and <code>JCommon</code>.</p>
  
  <p>I now have one compile error, described below:</p>
  
  <pre><code>The type org.jfree.data.general.Series cannot be resolved.
  It is indirectly referenced from required .class files.
  </code></pre>
  
  <p>I have found a number of questions and answers about this, but they seem to relate to the absence of <code>JCommon</code>. I have <code>JCommon</code> in my dependencies, and I have checked the specific class that is referred to is actually in the <code>jfreechart.jar</code> file with 7-zip.
  Below is the code fragment with the error, which occurs on the last else statement <code>results.add(…)</code>.</p>
  
  <pre><code>public XYDataset getMetricHistogramData(Timestamp t1, Timestamp t2){
      int index1=-1;
      Timestamp startTime,endTime;
      TimePeriodValues results = new TimePeriodValues(this.type.name());
      final TimePeriodValuesCollection results1 = new TimePeriodValuesCollection();
  
      if (t1.before(earliest)||t1.after(latest)||(readings.size()&lt;=1)) return null; // won't find a value for the timestamp t1
      if (t2.before(earliest)||t2.after(latest)) return null; // won't find a value for the timestamp t2
  
      for(int i = 0;i&lt;readings.size();i++){
          if (readings.get(i).timestamp().equals(t1)){
              index1=i;
              break;
          }
          if (readings.get(i).timestamp().after(t1)){
              index1=i-1;
              break;
          }       
      }
      // index1 now contains the index of the starting timestamp
      for (int i=index1; i&lt;(readings.size()-1); i++){
          startTime = readings.get(i).timestamp();
          if(startTime.after(t2)) break;
          //endTime = new Timestamp(Math.abs(readings.get(i+1).timestamp().getTime()-Timestamped.SECOND_IN_MS));
          endTime = readings.get(i+1).timestamp();
          if (endTime.before(startTime))
              SmartPower.getMain().getFrame().displayLog("Bad Timestamps "+startTime + " - " + endTime+"\n\r");
          else results.add(new SimpleTimePeriod(startTime, endTime), readings.get(i).value());
      }
      results1.addSeries(results);
      return results1;
  }
  </code></pre>
  
  <p>This is my pom.xml file</p>
  
  <pre><code>&lt;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"&gt;
    &lt;modelVersion&gt;4.0.0&lt;/modelVersion&gt;
    &lt;groupId&gt;SmartPower&lt;/groupId&gt;
    &lt;artifactId&gt;SmartPower&lt;/artifactId&gt;
    &lt;version&gt;0.0.1-SNAPSHOT&lt;/version&gt;
    &lt;build&gt;
      &lt;sourceDirectory&gt;src&lt;/sourceDirectory&gt;
      &lt;resources&gt;
        &lt;resource&gt;
          &lt;directory&gt;src&lt;/directory&gt;
          &lt;excludes&gt;
            &lt;exclude&gt;**/*.java&lt;/exclude&gt;
          &lt;/excludes&gt;
        &lt;/resource&gt;
      &lt;/resources&gt;
      &lt;plugins&gt;
        &lt;plugin&gt;
          &lt;artifactId&gt;maven-compiler-plugin&lt;/artifactId&gt;
          &lt;version&gt;3.5.1&lt;/version&gt;
          &lt;configuration&gt;
            &lt;source&gt;1.8&lt;/source&gt;
            &lt;target&gt;1.8&lt;/target&gt;
          &lt;/configuration&gt;
        &lt;/plugin&gt;
      &lt;/plugins&gt;
    &lt;/build&gt;
    &lt;dependencies&gt;
      &lt;!-- https://mvnrepository.com/artifact/org.eclipse.persistence/javax.persistence --&gt;
      &lt;dependency&gt;
        &lt;groupId&gt;org.eclipse.persistence&lt;/groupId&gt;
        &lt;artifactId&gt;javax.persistence&lt;/artifactId&gt;
        &lt;version&gt;2.1.1&lt;/version&gt;
      &lt;/dependency&gt;
      &lt;!-- https://mvnrepository.com/artifact/org.jfree/jfreechart --&gt;
      &lt;dependency&gt;
        &lt;groupId&gt;org.jfree&lt;/groupId&gt;
        &lt;artifactId&gt;jfreechart&lt;/artifactId&gt;
        &lt;version&gt;1.0.19&lt;/version&gt;
      &lt;/dependency&gt;
      &lt;!-- https://mvnrepository.com/artifact/org.jfree/jcommon --&gt;
      &lt;dependency&gt;
        &lt;groupId&gt;org.jfree&lt;/groupId&gt;
        &lt;artifactId&gt;jcommon&lt;/artifactId&gt;
      &lt;version&gt;1.0.23&lt;/version&gt; 
      &lt;/dependency&gt;
      &lt;!-- https://mvnrepository.com/artifact/com.jgoodies/forms --&gt;
      &lt;dependency&gt;
        &lt;groupId&gt;com.jgoodies&lt;/groupId&gt;
        &lt;artifactId&gt;forms&lt;/artifactId&gt;
        &lt;version&gt;1.2.1&lt;/version&gt;
      &lt;/dependency&gt;
      &lt;!-- https://mvnrepository.com/artifact/org.apache.derby/derby --&gt;
      &lt;dependency&gt;
        &lt;groupId&gt;org.apache.derby&lt;/groupId&gt;
        &lt;artifactId&gt;derby&lt;/artifactId&gt;
        &lt;version&gt;10.12.1.1&lt;/version&gt;
  &lt;/dependency&gt;
  
    &lt;/dependencies&gt;
  &lt;/project&gt;
  </code></pre>
  
  <p>Neon was a clean install about a week ago on windows 10.</p>
  
  <p>Any pointers would be appreciated.</p>