title: NoClassDefFound Error in this Java Code
body: <p>I am facing an error in this code.</p>
  
  <pre><code>import java.awt.Color;
  import org.jfree.chart.ChartFactory;
  import org.jfree.chart.ChartFrame;
  import org.jfree.chart.JFreeChart;
  import org.jfree.chart.plot.CategoryPlot;
  import org.jfree.chart.plot.PlotOrientation;
  import org.jfree.data.category.DefaultCategoryDataset;
  public void simplebarchart()
  {
     DefaultCategoryDataset dataset=new DefaultCategoryDataset() ;  
     dataset.setValue(80, "Marks", "Student1");
     dataset.setValue(70, "Marks", "Student2");
     dataset.setValue(65, "Marks", "Student3");
     dataset.setValue(90, "Marks", "Student4");
     JFreeChart c=ChartFactory.createBarChart("Student Score" ,"Student Name", "Marks",dataset, 
     PlotOrientation.VERTICAL, false, true, false);
     CategoryPlot p=c.getCategoryPlot();
     p.setRangeGridlinePaint(Color.BLACK);
     ChartFrame frame=new ChartFrame("Bar Chart",c);
     frame.setVisible(true);
     frame.setSize(450, 350);
  
  }
  </code></pre>
  
  <p>The error is given below</p>
  
  <pre><code>Exception in thread "AWT-EventQueue-0" java.lang.NoClassDefFoundError: 
  
   org/jfree/util/PublicCloneable
  at java.lang.ClassLoader.defineClass1(Native Method)
  at java.lang.ClassLoader.defineClass(ClassLoader.java:792)
  at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
  at java.net.URLClassLoader.defineClass(URLClassLoader.java:449)
  at java.net.URLClassLoader.access$100(URLClassLoader.java:71)
  </code></pre>
  
  <p>Why do I get this error?</p>