public class RowSetDynaClass extends Object implements DynaClass, 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.
| Modifier and Type | Field and 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 Map<String,DynaProperty> |
propertiesMap
The set of dynamic properties that are part of this
DynaClass, keyed by the property name. |
protected List<DynaBean> |
rows
The list of
DynaBeans representing the contents of
the original ResultSet on which this
RowSetDynaClass was based. |
| Constructor and Description |
|---|
RowSetDynaClass(ResultSet resultSet)
Construct a new
RowSetDynaClass for the specified
ResultSet. |
RowSetDynaClass(ResultSet resultSet,
boolean lowerCase)
Construct a new
RowSetDynaClass for the specified
ResultSet. |
RowSetDynaClass(ResultSet resultSet,
boolean lowerCase,
boolean useColumnLabel)
Construct a new
RowSetDynaClass for the specified
ResultSet. |
RowSetDynaClass(ResultSet resultSet,
boolean lowerCase,
int limit)
Construct a new
RowSetDynaClass for the specified
ResultSet. |
RowSetDynaClass(ResultSet resultSet,
boolean lowerCase,
int limit,
boolean useColumnLabel)
Construct a new
RowSetDynaClass for the specified
ResultSet. |
RowSetDynaClass(ResultSet resultSet,
int limit)
Construct a new
RowSetDynaClass for the specified
ResultSet. |
| Modifier and Type | Method and Description |
|---|---|
protected void |
copy(ResultSet resultSet)
|
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(ResultSetMetaData metadata,
int i)
Factory method to create a new DynaProperty for the given index
into the result set metadata.
|
protected String |
getColumnName(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(String name)
Return a property descriptor for the specified property, if it
exists; otherwise, return
null. |
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 Object |
getObject(ResultSet resultSet,
String name)
Get a column value from a
ResultSet for the specified name. |
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(ResultSet resultSet)
Introspect the metadata associated with our result set, and populate
the
properties and propertiesMap instance
variables. |
protected Class<?> |
loadClass(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.
|
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, waitgetDynaProperties, getDynaProperty, getName, newInstanceprotected 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.
protected List<DynaBean> rows
The list of DynaBeans representing the contents of
the original ResultSet on which this
RowSetDynaClass was based.
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 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.
public RowSetDynaClass(ResultSet resultSet) throws SQLException
Construct a new RowSetDynaClass 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 wrappedNullPointerException - if resultSet
is nullSQLException - if the metadata for this result set
cannot be introspectedpublic RowSetDynaClass(ResultSet resultSet, int limit) throws SQLException
Construct a new RowSetDynaClass for the specified
ResultSet. The property names corresponding
to column names in the result set will be lower cased.
limit is not less than 0, max limit
number of rows will be copied into the list.resultSet - The result set to be wrappedlimit - The maximum for the size of the result.NullPointerException - if resultSet
is nullSQLException - if the metadata for this result set
cannot be introspectedpublic RowSetDynaClass(ResultSet resultSet, boolean lowerCase) throws 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.
limit is not less than 0, max limit
number of rows will be copied into the resultset.resultSet - The result set to be wrappedlowerCase - Should property names be lower cased?NullPointerException - if resultSet
is nullSQLException - if the metadata for this result set
cannot be introspectedpublic RowSetDynaClass(ResultSet resultSet, boolean lowerCase, int limit) throws 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.
resultSet - The result set to be wrappedlowerCase - Should property names be lower cased?limit - Maximum limit for the List of DynaBeanNullPointerException - if resultSet
is nullSQLException - if the metadata for this result set
cannot be introspectedpublic RowSetDynaClass(ResultSet resultSet, boolean lowerCase, boolean useColumnLabel) throws 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.
resultSet - The result set to be wrappedlowerCase - Should property names be lower cased?useColumnLabel - true if the column label should be used, otherwise falseNullPointerException - if resultSet
is nullSQLException - if the metadata for this result set
cannot be introspectedpublic RowSetDynaClass(ResultSet resultSet, boolean lowerCase, int limit, boolean useColumnLabel) throws 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.
resultSet - The result set to be wrappedlowerCase - Should property names be lower cased?limit - Maximum limit for the List of DynaBeanuseColumnLabel - true if the column label should be used, otherwise falseNullPointerException - if resultSet
is nullSQLException - if the metadata for this result set
cannot be introspectedpublic 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.
List of DynaBean instancesprotected void copy(ResultSet resultSet) throws 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().
resultSet - The ResultSet whose data is to be
copiedSQLException - if an error is encountered copying the dataprotected DynaBean createDynaBean()
Create and return a new DynaBean instance to be used for
representing a row in the underlying result set.
DynaBean instancepublic 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.
public DynaProperty getDynaProperty(String name)
Return a property descriptor for the specified property, if it
exists; otherwise, return null.
getDynaProperty in interface DynaClassname - Name of the dynamic property for which a descriptor
is requestedIllegalArgumentException - if no property name is specifiedpublic 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 in interface DynaClasspublic DynaBean newInstance() throws IllegalAccessException, InstantiationException
Instantiate and return a new DynaBean instance, associated with this DynaClass. NOTE - This operation is not supported, and throws an exception.
newInstance in interface DynaClassDynaBean instanceIllegalAccessException - if the Class or the appropriate
constructor is not accessibleInstantiationException - if this Class represents an abstract
class, an array class, a primitive type, or void; or if instantiation
fails for some other reasonpublic void setUseColumnLabel(boolean useColumnLabel)
useColumnLabel - true if the column label should be used, otherwise falseprotected Class<?> loadClass(String className) throws 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.
className - The name of the class to loadSQLException - if an exception was thrown trying to load
the specified classprotected 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 metadatai - is the column index in the metadataSQLException - If an error occurs accessing the SQL metadataprotected 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 introspectedSQLException - if an error is encountered processing the
result set metadataprotected Object getObject(ResultSet resultSet, String name) throws SQLException
ResultSet for the specified name.resultSet - The result setname - The property nameSQLException - if an error occursCopyright © 2000–2019 The Apache Software Foundation. All rights reserved.