Package org.apache.commons.beanutils

Class RowSetDynaClass

  • All Implemented Interfaces:
    java.io.Serializable, DynaClass
    public class RowSetDynaClass
extends java.lang.Object
implements DynaClass, java.io.Serializable

    Implementation of DynaClass that creates an in-memory collection of DynaBeans representing the results of an SQL query. Once the DynaClass instance has been created, the JDBC ResultSet and Statement on which it is based can be closed, and the underlying Connection can be returned to its connection pool (if you are using one).

    The normal usage pattern is something like:

       Connection conn = ...;  // Acquire connection from pool
   Statement stmt = conn.createStatement();
   ResultSet rs = stmt.executeQuery("SELECT ...");
   RowSetDynaClass rsdc = new RowSetDynaClass(rs);
   rs.close();
   stmt.close();
   ...;                    // Return connection to pool
   List rows = rsdc.getRows();
   ...;                   // Process the rows as desired

    Each column in the result set will be represented as a DynaBean property of the corresponding name (optionally forced to lower case for portability). There will be one DynaBean in the List returned by getRows() for each row in the original ResultSet.

    In general, instances of RowSetDynaClass can be serialized and deserialized, which will automatically include the list of DynaBeans representing the data content. The only exception to this rule would be when the underlying property values that were copied from the ResultSet originally cannot themselves be serialized. Therefore, a RowSetDynaClass makes a very convenient mechanism for transporting data sets to remote Java-based application components.

    Version:
    $Id$
    See Also:
    Serialized Form

    • Field Summary

      Fields 
      Modifier and Type Field Description
      protected int limit
      Limits the size of the returned list.
      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.util.List<DynaBean> rows
      The list of DynaBeans representing the contents of the original ResultSet on which this RowSetDynaClass was based.

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      protected void copy​(java.sql.ResultSet resultSet)
      Copy the column values for each row in the specified ResultSet into a newly created DynaBean, and add this bean to the list of DynaBeans that will later by returned by a call to getRows().
      protected DynaBean createDynaBean()
      Create and return a new DynaBean instance to be used for representing a row in the underlying result set.
      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.util.List<DynaBean> getRows()
      Return a List containing the DynaBeans that represent the contents of each Row from the ResultSet that was the basis of this RowSetDynaClass instance.
      protected void introspect​(java.sql.ResultSet resultSet)
      Introspect the metadata associated with our result set, and populate the properties and propertiesMap instance variables.
      protected java.lang.Class<?> loadClass​(java.lang.String className)
      Loads and returns the Class of the given name.
      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

      • limit

        protected int limit

        Limits the size of the returned list. The call to getRows() will return at most limit number of rows. If less than or equal to 0, does not limit the size of the result.

      • rows

        protected java.util.List<DynaBean> rows

        The list of DynaBeans representing the contents of the original ResultSet on which this RowSetDynaClass was based.

      • 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

      • RowSetDynaClass

        public RowSetDynaClass​(java.sql.ResultSet resultSet)
                throws java.sql.SQLException

        Construct a new RowSetDynaClass 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

      • RowSetDynaClass

        public RowSetDynaClass​(java.sql.ResultSet resultSet,
                       int limit)
                throws java.sql.SQLException

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

        If limit is not less than 0, max limit number of rows will be copied into the list.
        Parameters:
        resultSet - The result set to be wrapped
        limit - The maximum for the size of the result.
        Throws:
        java.lang.NullPointerException - if resultSet is null
        java.sql.SQLException - if the metadata for this result set cannot be introspected

      • RowSetDynaClass

        public RowSetDynaClass​(java.sql.ResultSet resultSet,
                       boolean lowerCase)
                throws java.sql.SQLException

        Construct a new RowSetDynaClass 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.

        If limit is not less than 0, max limit number of rows will be copied into the resultset.
        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

      • RowSetDynaClass

        public RowSetDynaClass​(java.sql.ResultSet resultSet,
                       boolean lowerCase,
                       int limit)
                throws java.sql.SQLException

        Construct a new RowSetDynaClass 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?
        limit - Maximum limit for the List of DynaBean
        Throws:
        java.lang.NullPointerException - if resultSet is null
        java.sql.SQLException - if the metadata for this result set cannot be introspected

      • RowSetDynaClass

        public RowSetDynaClass​(java.sql.ResultSet resultSet,
                       boolean lowerCase,
                       boolean useColumnLabel)
                throws java.sql.SQLException

        Construct a new RowSetDynaClass 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

      • RowSetDynaClass

        public RowSetDynaClass​(java.sql.ResultSet resultSet,
                       boolean lowerCase,
                       int limit,
                       boolean useColumnLabel)
                throws java.sql.SQLException

        Construct a new RowSetDynaClass 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?
        limit - Maximum limit for the List of DynaBean
        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

      • getRows

        public java.util.List<DynaBean> getRows()

        Return a List containing the DynaBeans that represent the contents of each Row from the ResultSet that was the basis of this RowSetDynaClass instance. These DynaBeans are disconnected from the database itself, so there is no problem with modifying the contents of the list, or the values of the properties of these DynaBeans. However, it is the application's responsibility to persist any such changes back to the database, if it so desires.

        Returns:
        A List of DynaBean instances

      • copy

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

        Copy the column values for each row in the specified ResultSet into a newly created DynaBean, and add this bean to the list of DynaBeans that will later by returned by a call to getRows().

        Parameters:
        resultSet - The ResultSet whose data is to be copied
        Throws:
        java.sql.SQLException - if an error is encountered copying the data

      • createDynaBean

        protected DynaBean createDynaBean()

        Create and return a new DynaBean instance to be used for representing a row in the underlying result set.

        Returns:
        A new DynaBean instance

      • 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

      • loadClass

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

        Loads and returns the Class of the given name. By default, a load from the thread context class loader is attempted. If there is no such class loader, the class loader used to load this class will be utilized.

        Parameters:
        className - The name of the class to load
        Returns:
        The loaded class
        Throws:
        java.sql.SQLException - if an exception was thrown trying to load the specified class

      • 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).