instancequery.java

Java 编写的多种数据挖掘算法 包括聚类、分类、预处理等

      if (m_PreparedStatement.getUpdateCount() == -1) {
        throw new Exception("Query didn't produce results");
      }
      else {
        if (m_Debug) 
          System.err.println(m_PreparedStatement.getUpdateCount() 
              + " rows affected.");
        return null;
      }
    }
    ResultSet rs = getResultSet();
    if (m_Debug) 
      System.err.println("Getting metadata...");
    ResultSetMetaData md = rs.getMetaData();
    if (m_Debug) 
      System.err.println("Completed getting metadata...");
    // Determine structure of the instances
    int numAttributes = md.getColumnCount();
    int [] attributeTypes = new int [numAttributes];
    Hashtable [] nominalIndexes = new Hashtable [numAttributes];
    FastVector [] nominalStrings = new FastVector [numAttributes];
    for (int i = 1; i <= numAttributes; i++) {
      /* switch (md.getColumnType(i)) {
      case Types.CHAR:
      case Types.VARCHAR:
      case Types.LONGVARCHAR:
      case Types.BINARY:
      case Types.VARBINARY:
      case Types.LONGVARBINARY:*/
      
      switch (translateDBColumnType(md.getColumnTypeName(i))) {
	
      case STRING :
	//System.err.println("String --> nominal");
	attributeTypes[i - 1] = Attribute.NOMINAL;
	nominalIndexes[i - 1] = new Hashtable();
	nominalStrings[i - 1] = new FastVector();
	break;
      case BOOL:
	//System.err.println("boolean --> nominal");
	attributeTypes[i - 1] = Attribute.NOMINAL;
	nominalIndexes[i - 1] = new Hashtable();
	nominalIndexes[i - 1].put("false", new Double(0));
	nominalIndexes[i - 1].put("true", new Double(1));
	nominalStrings[i - 1] = new FastVector();
	nominalStrings[i - 1].addElement("false");
	nominalStrings[i - 1].addElement("true");
	break;
      case DOUBLE:
	//System.err.println("BigDecimal --> numeric");
	attributeTypes[i - 1] = Attribute.NUMERIC;
	break;
      case BYTE:
	//System.err.println("byte --> numeric");
	attributeTypes[i - 1] = Attribute.NUMERIC;
	break;
      case SHORT:
	//System.err.println("short --> numeric");
	attributeTypes[i - 1] = Attribute.NUMERIC;
	break;
      case INTEGER:
	//System.err.println("int --> numeric");
	attributeTypes[i - 1] = Attribute.NUMERIC;
	break;
      case LONG:
	//System.err.println("long --> numeric");
	attributeTypes[i - 1] = Attribute.NUMERIC;
	break;
      case FLOAT:
	//System.err.println("float --> numeric");
	attributeTypes[i - 1] = Attribute.NUMERIC;
	break;
      case DATE:
	attributeTypes[i - 1] = Attribute.DATE;
	break;
      default:
	//System.err.println("Unknown column type");
	attributeTypes[i - 1] = Attribute.STRING;
      }
    }

    // Step through the tuples
    if (m_Debug) 
      System.err.println("Creating instances...");
    FastVector instances = new FastVector();
    int rowCount = 0;
    while(rs.next()) {
      if (rowCount % 100 == 0) {
        if (m_Debug)  {
	  System.err.print("read " + rowCount + " instances \r");
	  System.err.flush();
        }
      }
      double[] vals = new double[numAttributes];
      for(int i = 1; i <= numAttributes; i++) {
	/*switch (md.getColumnType(i)) {
	case Types.CHAR:
	case Types.VARCHAR:
	case Types.LONGVARCHAR:
	case Types.BINARY:
	case Types.VARBINARY:
	case Types.LONGVARBINARY:*/
	switch (translateDBColumnType(md.getColumnTypeName(i))) {
	case STRING :
	  String str = rs.getString(i);
	  
	  if (rs.wasNull()) {
	    vals[i - 1] = Instance.missingValue();
	  } else {
	    Double index = (Double)nominalIndexes[i - 1].get(str);
	    if (index == null) {
	      index = new Double(nominalStrings[i - 1].size());
	      nominalIndexes[i - 1].put(str, index);
	      nominalStrings[i - 1].addElement(str);
	    }
	    vals[i - 1] = index.doubleValue();
	  }
	  break;
	case BOOL:
	  boolean boo = rs.getBoolean(i);
	  if (rs.wasNull()) {
	    vals[i - 1] = Instance.missingValue();
	  } else {
	    vals[i - 1] = (boo ? 1.0 : 0.0);
	  }
	  break;
	case DOUBLE:
	  //	  BigDecimal bd = rs.getBigDecimal(i, 4); 
	  double dd = rs.getDouble(i);
	  // Use the column precision instead of 4?
	  if (rs.wasNull()) {
	    vals[i - 1] = Instance.missingValue();
	  } else {
	    //	    newInst.setValue(i - 1, bd.doubleValue());
	    vals[i - 1] =  dd;
	  }
	  break;
	case BYTE:
	  byte by = rs.getByte(i);
	  if (rs.wasNull()) {
	    vals[i - 1] = Instance.missingValue();
	  } else {
	    vals[i - 1] = (double)by;
	  }
	  break;
	case SHORT:
	  short sh = rs.getByte(i);
	  if (rs.wasNull()) {
	    vals[i - 1] = Instance.missingValue();
	  } else {
	    vals[i - 1] = (double)sh;
	  }
	  break;
	case INTEGER:
	  int in = rs.getInt(i);
	  if (rs.wasNull()) {
	    vals[i - 1] = Instance.missingValue();
	  } else {
	    vals[i - 1] = (double)in;
	  }
	  break;
	case LONG:
	  long lo = rs.getLong(i);
	  if (rs.wasNull()) {
	    vals[i - 1] = Instance.missingValue();
	  } else {
	    vals[i - 1] = (double)lo;
	  }
	  break;
	case FLOAT:
	  float fl = rs.getFloat(i);
	  if (rs.wasNull()) {
	    vals[i - 1] = Instance.missingValue();
	  } else {
	    vals[i - 1] = (double)fl;
	  }
	  break;
	case DATE:
          Date date = rs.getDate(i);
          if (rs.wasNull()) {
	    vals[i - 1] = Instance.missingValue();
	  } else {
            // TODO: Do a value check here.
            vals[i - 1] = (double)date.getTime();
          }
          break;
	default:
	  vals[i - 1] = Instance.missingValue();
	}
      }
      Instance newInst;
      if (m_CreateSparseData) {
	newInst = new SparseInstance(1.0, vals);
      } else {
	newInst = new Instance(1.0, vals);
      }
      instances.addElement(newInst);
      rowCount++;
    }
    //disconnectFromDatabase();  (perhaps other queries might be made)
    
    // Create the header and add the instances to the dataset
    if (m_Debug) 
      System.err.println("Creating header...");
    FastVector attribInfo = new FastVector();
    for (int i = 0; i < numAttributes; i++) {
      /* Fix for databases that uppercase column names */
      String attribName = attributeCaseFix(md.getColumnName(i + 1));
      switch (attributeTypes[i]) {
      case Attribute.NOMINAL:
	attribInfo.addElement(new Attribute(attribName, nominalStrings[i]));
	break;
      case Attribute.NUMERIC:
	attribInfo.addElement(new Attribute(attribName));
	break;
      case Attribute.STRING:
	attribInfo.addElement(new Attribute(attribName, (FastVector)null));
	break;
      case Attribute.DATE:
	attribInfo.addElement(new Attribute(attribName, (String)null));
	break;
      default:
	throw new Exception("Unknown attribute type");
      }
    }
    Instances result = new Instances("QueryResult", attribInfo, 
				     instances.size());
    for (int i = 0; i < instances.size(); i++) {
      result.add((Instance)instances.elementAt(i));
    }
    rs.close();
   
    return result;
  }

  /**
   * Test the class from the command line. The instance
   * query should be specified with -Q sql_query
   *
   * @param args contains options for the instance query
   */
  public static void main(String args[]) {

    try {
      InstanceQuery iq = new InstanceQuery();
      String query = Utils.getOption('Q', args);
      if (query.length() == 0) {
	iq.setQuery("select * from Experiment_index");
      } else {
	iq.setQuery(query);
      }
      iq.setOptions(args);
      try {
	Utils.checkForRemainingOptions(args);
      } catch (Exception e) {
	System.err.println("Options for weka.experiment.InstanceQuery:\n");
	Enumeration en = iq.listOptions();
	while (en.hasMoreElements()) {
	  Option o = (Option)en.nextElement();
	  System.err.println(o.synopsis()+"\n"+o.description());
	}
	System.exit(1);
      }
     
      Instances aha = iq.retrieveInstances();
      iq.disconnectFromDatabase();
      // query returned no result -> exit
      if (aha == null)
        return;
      // The dataset may be large, so to make things easier we'll
      // output an instance at a time (rather than having to convert
      // the entire dataset to one large string)
      System.out.println(new Instances(aha, 0));
      for (int i = 0; i < aha.numInstances(); i++) {
	System.out.println(aha.instance(i));
      }
    } catch(Exception e) {
      e.printStackTrace();
      System.err.println(e.getMessage());
    }
  }
}