? ResultSetDynaClass

java.lang.Object
org.apache.commons.beanutils.ResultSetDynaClass
????????:
Serializable, DynaClass

public class ResultSetDynaClass extends Object implements DynaClass

Implementation of 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);
   }
 
??:
$Id$
????:
  • ??????

    • resultSet

      protected ResultSet resultSet

      The ResultSet we are wrapping.

    • lowerCase

      protected boolean lowerCase

      Flag defining whether column names should be lower cased when converted to property names.

    • properties

      protected DynaProperty[] properties

      The set of dynamic properties that are part of this DynaClass.

    • propertiesMap

      protected Map<String,DynaProperty> propertiesMap

      The set of dynamic properties that are part of this DynaClass, keyed by the property name. Individual descriptor instances will be the same instances as those in the properties list.

  • ???????

    • 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.

      ??:
      resultSet - The result set to be wrapped
      ??:
      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.

      ??:
      resultSet - The result set to be wrapped
      lowerCase - Should property names be lower cased?
      ??:
      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.

      ??:
      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
      ??:
      NullPointerException - if resultSet is null
      SQLException - if the metadata for this result set cannot be introspected
      ???????:
      1.8.3
  • ??????

    • 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.

      ??:
      An Iterator of DynaBean instances
    • getObjectFromResultSet

      Get a value from the ResultSet for the specified property name.
      ??:
      name - The property name
      ??:
      The value
      ??:
      SQLException - if an error occurs
      ???????:
      1.8.0
    • 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.

      ??:
      className - The name of the class to load
      ??:
      The loaded class
      ??:
      SQLException - if the class cannot be loaded
    • getName

      public String getName()

      Return the name of this DynaClass (analogous to the getName() method of java.lang.Class</code), which allows the same DynaClass implementation class to support different dynamic classes, with different sets of properties.

      ???:
      getName ???? DynaClass
      ??:
      the name of the DynaClass
    • getDynaProperty

      public DynaProperty getDynaProperty(String name)

      Return a property descriptor for the specified property, if it exists; otherwise, return null.

      ???:
      getDynaProperty ???? DynaClass
      ??:
      name - Name of the dynamic property for which a descriptor is requested
      ??:
      The descriptor for the specified property
      ??:
      IllegalArgumentException - if no property name is specified
    • getDynaProperties

      public DynaProperty[] getDynaProperties()

      Return an array of ProperyDescriptors for the properties currently defined in this DynaClass. If no properties are defined, a zero-length array will be returned.

      ???:
      getDynaProperties ???? DynaClass
      ??:
      the set of properties for this DynaClass
    • newInstance

      Instantiate and return a new DynaBean instance, associated with this DynaClass. NOTE - This operation is not supported, and throws an exception.

      ???:
      newInstance ???? DynaClass
      ??:
      A new DynaBean instance
      ??:
      IllegalAccessException - if the Class or the appropriate constructor is not accessible
      InstantiationException - if this Class represents an abstract class, an array class, a primitive type, or void; or if instantiation fails for some other reason
    • setUseColumnLabel

      public void setUseColumnLabel(boolean useColumnLabel)
      Set whether the column label or name should be used for the property name.
      ??:
      useColumnLabel - true if the column label should be used, otherwise false
    • createDynaProperty

      protected DynaProperty createDynaProperty(ResultSetMetaData metadata, int i) throws SQLException

      Factory method to create a new DynaProperty for the given index into the result set metadata.

      ??:
      metadata - is the result set metadata
      i - is the column index in the metadata
      ??:
      the newly created DynaProperty instance
      ??:
      SQLException - If an error occurs accessing the SQL metadata
    • introspect

      protected void introspect(ResultSet resultSet) throws SQLException

      Introspect the metadata associated with our result set, and populate the properties and propertiesMap instance variables.

      ??:
      resultSet - The resultSet whose metadata is to be introspected
      ??:
      SQLException - if an error is encountered processing the result set metadata
    • getObject

      protected Object getObject(ResultSet resultSet, String name) throws SQLException
      Get a column value from a ResultSet for the specified name.
      ??:
      resultSet - The result set
      name - The property name
      ??:
      The value
      ??:
      SQLException - if an error occurs
    • getColumnName

      protected String getColumnName(String name)
      Get the table column name for the specified property name.
      ??:
      name - The property name
      ??:
      The column name (which can be different if the lowerCase option is used).