ListingWekaInstances.java

Instances dataSet = // ...

// Showing attribute-type pairs of dataSet
// Analogy with SQL: print field and field type of a table
Enumeration attributes = dataSet.enumerateAttributes();
while (attributes.hasMoreElements()) {
  Attribute attribute = (Attribute) attributes.nextElement();
  System.out.println(attribute.name() + ": " +
    Attribute.typeToString(attribute.type()));
}

// Listing each instance's attribute-value pairs of dataSet
// Analogy with SQL: print all records of a table
Enumeration instances = dataSet.enumerateInstances();
while (instances.hasMoreElements()) {
  Instance instance = (Instance) instances.nextElement();
  Enumeration instanceAttribute = instance.enumerateAttributes();
  while (instanceAttribute.hasMoreElements()) {
    Attribute a = (Attribute) instanceAttribute.nextElement();
    System.out.println(a.name() + ": " + instance.toString(a));
  }
  System.out.println();
}