Package org.apache.commons.beanutils

Class ResultSetDynaClass

java.lang.Object
org.apache.commons.beanutils.JDBCDynaClass
org.apache.commons.beanutils.ResultSetDynaClass
All Implemented Interfaces:
Serializable, DynaClass
public class ResultSetDynaClass extends JDBCDynaClass

Implements DynaClass for DynaBeans that wrap the java.sql.Row objects of a java.sql.ResultSet. The normal usage pattern is something like:

   ResultSet rs = ...;
   ResultSetDynaClass rsdc = new ResultSetDynaClass(rs);
   Iterator rows = rsdc.iterator();
   while (rows.hasNext())  {
     DynaBean row = (DynaBean) rows.next();
     ... process this row ...
   }
   rs.close();

Each column in the result set will be represented as a DynaBean property of the corresponding name (optionally forced to lower case for portability).

WARNING - Any DynaBean instance returned by this class, or from the Iterator returned by the iterator() method, is directly linked to the row that the underlying result set is currently positioned at. This has the following implications:

  • Once you retrieve a different DynaBean instance, you should no longer use any previous instance.
  • Changing the position of the underlying result set will change the data that the DynaBean references.
  • Once the underlying result set is closed, the DynaBean instance may no longer be used.

Any database data that you wish to utilize outside the context of the current row of an open result set must be copied. For example, you could use the following code to create standalone copies of the information in a result set:

   ArrayList results = new ArrayList(); // To hold copied list
   ResultSetDynaClass rsdc = ...;
   DynaProperty[] properties = rsdc.getDynaProperties();
   BasicDynaClass bdc =
     new BasicDynaClass("foo", BasicDynaBean.class,
                        rsdc.getDynaProperties());
   Iterator rows = rsdc.iterator();
   while (rows.hasNext()) {
     DynaBean oldRow = (DynaBean) rows.next();
     DynaBean newRow = bdc.newInstance();
     PropertyUtils.copyProperties(newRow, oldRow);
     results.add(newRow);
   }
See Also:

  • Field Details

    • serialVersionUID

      private static final long serialVersionUID
      See Also:

    • resultSet

      protected ResultSet resultSet

      The ResultSet we are wrapping.

  • Constructor Details

    • ResultSetDynaClass

      public ResultSetDynaClass(ResultSet resultSet) throws SQLException

      Construct a new ResultSetDynaClass for the specified ResultSet. The property names corresponding to column names in the result set will be lower cased.

      Parameters:
      resultSet - The result set to be wrapped
      Throws:
      NullPointerException - if resultSet is null
      SQLException - if the metadata for this result set cannot be introspected

    • ResultSetDynaClass

      public ResultSetDynaClass(ResultSet resultSet, boolean lowerCase) throws SQLException

      Construct a new ResultSetDynaClass for the specified ResultSet. The property names corresponding to the column names in the result set will be lower cased or not, depending on the specified lowerCase value.

      WARNING - If you specify false for lowerCase, the returned property names will exactly match the column names returned by your JDBC driver. Because different drivers might return column names in different cases, the property names seen by your application will vary depending on which JDBC driver you are using.

      Parameters:
      resultSet - The result set to be wrapped
      lowerCase - Should property names be lower cased?
      Throws:
      NullPointerException - if resultSet is null
      SQLException - if the metadata for this result set cannot be introspected

    • ResultSetDynaClass

      public ResultSetDynaClass(ResultSet resultSet, boolean lowerCase, boolean useColumnLabel) throws SQLException

      Construct a new ResultSetDynaClass for the specified ResultSet. The property names corresponding to the column names in the result set will be lower cased or not, depending on the specified lowerCase value.

      WARNING - If you specify false for lowerCase, the returned property names will exactly match the column names returned by your JDBC driver. Because different drivers might return column names in different cases, the property names seen by your application will vary depending on which JDBC driver you are using.

      Parameters:
      resultSet - The result set to be wrapped
      lowerCase - Should property names be lower cased?
      useColumnLabel - true if the column label should be used, otherwise false
      Throws:
      NullPointerException - if resultSet is null
      SQLException - if the metadata for this result set cannot be introspected
      Since:
      1.8.3

  • Method Details

    • getObjectFromResultSet

      public Object getObjectFromResultSet(String name) throws SQLException
      Get a value from the ResultSet for the specified property name.
      Parameters:
      name - The property name
      Returns:
      The value
      Throws:
      SQLException - if an error occurs
      Since:
      1.8.0

    • getResultSet

      ResultSet getResultSet()

      Return the result set we are wrapping.

    • iterator

      public Iterator<DynaBean> iterator()

      Return an Iterator of DynaBean instances for each row of the wrapped ResultSet, in "forward" order. Unless the underlying result set supports scrolling, this method should be called only once.

      Returns:
      An Iterator of DynaBean instances

    • loadClass

      protected Class<?> loadClass(String className) throws SQLException

      Loads the class of the given name which by default uses the class loader used to load this library. Dervations of this class could implement alternative class loading policies such as using custom ClassLoader or using the Threads's context class loader etc.

      Overrides:
      loadClass in class JDBCDynaClass
      Parameters:
      className - The name of the class to load
      Returns:
      The loaded class
      Throws:
      SQLException - if the class cannot be loaded