Package org.apache.commons.beanutils

Class ResultSetDynaClass

  • All Implemented Interfaces:
    java.io.Serializable, DynaClass
    public class ResultSetDynaClass
extends java.lang.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);
   }
    Version:
    $Id$
    See Also:
    Serialized Form

    • Field Summary

      Fields 
      Modifier and Type Field Description
      protected boolean lowerCase
      Flag defining whether column names should be lower cased when converted to property names.
      protected DynaProperty[] properties
      The set of dynamic properties that are part of this DynaClass.
      protected java.util.Map<java.lang.String,​DynaProperty> propertiesMap
      The set of dynamic properties that are part of this DynaClass, keyed by the property name.
      protected java.sql.ResultSet resultSet
      The ResultSet we are wrapping.

    • Constructor Summary

      Constructors 
      Constructor Description
      ResultSetDynaClass​(java.sql.ResultSet resultSet)
      Construct a new ResultSetDynaClass for the specified ResultSet.
      ResultSetDynaClass​(java.sql.ResultSet resultSet, boolean lowerCase)
      Construct a new ResultSetDynaClass for the specified ResultSet.
      ResultSetDynaClass​(java.sql.ResultSet resultSet, boolean lowerCase, boolean useColumnLabel)
      Construct a new ResultSetDynaClass for the specified ResultSet.

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      protected DynaProperty createDynaProperty​(java.sql.ResultSetMetaData metadata, int i)
      Factory method to create a new DynaProperty for the given index into the result set metadata.
      protected java.lang.String getColumnName​(java.lang.String name)
      Get the table column name for the specified property name.
      DynaProperty[] getDynaProperties()
      Return an array of ProperyDescriptors for the properties currently defined in this DynaClass.
      DynaProperty getDynaProperty​(java.lang.String name)
      Return a property descriptor for the specified property, if it exists; otherwise, return null.
      java.lang.String getName()
      Return the name of this DynaClass (analogous to the getName() method of java.lang.ClassDynaClass implementation class to support different dynamic classes, with different sets of properties.
      protected java.lang.Object getObject​(java.sql.ResultSet resultSet, java.lang.String name)
      Get a column value from a ResultSet for the specified name.
      java.lang.Object getObjectFromResultSet​(java.lang.String name)
      Get a value from the ResultSet for the specified property name.
      protected void introspect​(java.sql.ResultSet resultSet)
      Introspect the metadata associated with our result set, and populate the properties and propertiesMap instance variables.
      java.util.Iterator<DynaBean> iterator()
      Return an Iterator of DynaBean instances for each row of the wrapped ResultSet, in "forward" order.
      protected java.lang.Class<?> loadClass​(java.lang.String className)
      Loads the class of the given name which by default uses the class loader used to load this library.
      DynaBean newInstance()
      Instantiate and return a new DynaBean instance, associated with this DynaClass.
      void setUseColumnLabel​(boolean useColumnLabel)
      Set whether the column label or name should be used for the property name.

      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

    • Field Detail

      • resultSet

        protected java.sql.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 java.util.Map<java.lang.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.

    • Constructor Detail

      • ResultSetDynaClass

        public ResultSetDynaClass​(java.sql.ResultSet resultSet)
                   throws java.sql.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:
        java.lang.NullPointerException - if resultSet is null
        java.sql.SQLException - if the metadata for this result set cannot be introspected

      • ResultSetDynaClass

        public ResultSetDynaClass​(java.sql.ResultSet resultSet,
                          boolean lowerCase)
                   throws java.sql.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:
        java.lang.NullPointerException - if resultSet is null
        java.sql.SQLException - if the metadata for this result set cannot be introspected

      • ResultSetDynaClass

        public ResultSetDynaClass​(java.sql.ResultSet resultSet,
                          boolean lowerCase,
                          boolean useColumnLabel)
                   throws java.sql.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:
        java.lang.NullPointerException - if resultSet is null
        java.sql.SQLException - if the metadata for this result set cannot be introspected
        Since:
        1.8.3

    • Method Detail

      • iterator

        public java.util.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

      • getObjectFromResultSet

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

      • loadClass

        protected java.lang.Class<?> loadClass​(java.lang.String className)
                                throws java.sql.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.

        Parameters:
        className - The name of the class to load
        Returns:
        The loaded class
        Throws:
        java.sql.SQLException - if the class cannot be loaded

      • getName

        public java.lang.String getName()

        Return the name of this DynaClass (analogous to the getName() method of java.lang.ClassDynaClass implementation class to support different dynamic classes, with different sets of properties.

        Specified by:
        getName in interface DynaClass
        Returns:
        the name of the DynaClass

      • getDynaProperty

        public DynaProperty getDynaProperty​(java.lang.String name)

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

        Specified by:
        getDynaProperty in interface DynaClass
        Parameters:
        name - Name of the dynamic property for which a descriptor is requested
        Returns:
        The descriptor for the specified property
        Throws:
        java.lang.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.

        Specified by:
        getDynaProperties in interface DynaClass
        Returns:
        the set of properties for this DynaClass

      • newInstance

        public DynaBean newInstance()
                     throws java.lang.IllegalAccessException,
                            java.lang.InstantiationException

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

        Specified by:
        newInstance in interface DynaClass
        Returns:
        A new DynaBean instance
        Throws:
        java.lang.IllegalAccessException - if the Class or the appropriate constructor is not accessible
        java.lang.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.
        Parameters:
        useColumnLabel - true if the column label should be used, otherwise false

      • createDynaProperty

        protected DynaProperty createDynaProperty​(java.sql.ResultSetMetaData metadata,
                                          int i)
                                   throws java.sql.SQLException

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

        Parameters:
        metadata - is the result set metadata
        i - is the column index in the metadata
        Returns:
        the newly created DynaProperty instance
        Throws:
        java.sql.SQLException - If an error occurs accessing the SQL metadata

      • introspect

        protected void introspect​(java.sql.ResultSet resultSet)
                   throws java.sql.SQLException

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

        Parameters:
        resultSet - The resultSet whose metadata is to be introspected
        Throws:
        java.sql.SQLException - if an error is encountered processing the result set metadata

      • getObject

        protected java.lang.Object getObject​(java.sql.ResultSet resultSet,
                                     java.lang.String name)
                              throws java.sql.SQLException
        Get a column value from a ResultSet for the specified name.
        Parameters:
        resultSet - The result set
        name - The property name
        Returns:
        The value
        Throws:
        java.sql.SQLException - if an error occurs

      • getColumnName

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