OpenJDK 1.22 · com.sun.rowset.internal.CachedRowSetReader

The facility called by the RIOptimisticProvider object internally to read data into it. The calling RowSet object must have implemented the RowSetInternal interface and have the standard CachedRowSetReader object set as its reader.

This implementation always reads all rows of the data source, and it assumes that the command property for the caller is set with a query that is appropriate for execution by a PreparedStatement object.

Typically the SyncFactory manages the RowSetReader and the RowSetWriter implementations using SyncProvider objects. Standard JDBC RowSet implementations provide an object instance of this reader by invoking the SyncProvider.getRowSetReader() method.

Field Summary

Modifier and Type	Field and Description
private JdbcRowSetResourceBundle	resBundle
pack-priv static final long	serialVersionUID
private int	startPosition
private boolean	userCon
private int	writerCalls The field that keeps track of whether the writer associated with this `CachedRowSetReader` object's rowset has been called since the rowset was populated.

Constructor Summary

Access	Constructor and Description
public	CachedRowSetReader()

Method Summary

Modifier and Type	Method and Description
public Connection	Returns: a `Connection` object that represents a connection to the caller's data source connect(RowSetInternal a `RowSet` object that has implemented the `RowSetInternal` interface and had this `CachedRowSetReader` object set as its reader caller) Establishes a connection with the data source for the given `RowSet` object.
private void	decodeParams(Object[] an array of parameters to be used with the given `PreparedStatement` object params, PreparedStatement the `PreparedStatement` object that is the command for the calling rowset and into which the given parameters are to be set pstmt) Sets the parameter placeholders in the rowset's command (the given `PreparedStatement` object) with the parameters in the given array.
protected boolean	Returns: a boolean giving the status of whether the connection has been closed. getCloseConnection() Assists in determining whether the current connection was created by this CachedRowSet to ensure incorrect connections are not prematurely terminated.
public void	readData(RowSetInternal a `RowSet` object that has implemented the `RowSetInternal` interface and had this `CachedRowSetReader` object set as its reader caller) Implements javax.sql.RowSetReader.readData. Reads data from a data source and populates the given `RowSet` object with that data.
private void	readObject(ObjectInputStream ois)
public boolean	Returns: `true` if writer associated with this reader needs to reset the values of its fields; `false` otherwise reset() Checks to see if the writer associated with this reader needs to reset its state.
public void	setStartPosition(int integer indicating the position in the `ResultSet` to begin populating from. pos) This sets the start position in the ResultSet from where to begin.

Inherited from java.lang.Object:: clone equals finalize getClass hashCode notify notifyAll toString wait wait wait

Field Detail

resBundle	back to summary
private JdbcRowSetResourceBundle resBundle

serialVersionUID	back to summary
pack-priv static final long serialVersionUID

startPosition	back to summary
private int startPosition

userCon	back to summary
private boolean userCon

writerCalls back to summary

writerCalls	back to summary
private int writerCalls The field that keeps track of whether the writer associated with this `CachedRowSetReader` object's rowset has been called since the rowset was populated. When this `CachedRowSetReader` object reads data into its rowset, it sets the field `writerCalls` to 0. When the writer associated with the rowset is called to write data back to the underlying data source, its `writeData` method calls the method `CachedRowSetReader.reset`, which increments `writerCalls` and returns `true` if `writerCalls` is 1. Thus, `writerCalls` equals 1 after the first call to `writeData` that occurs after the rowset has had data read into it.

private int writerCalls

The field that keeps track of whether the writer associated with this CachedRowSetReader object's rowset has been called since the rowset was populated.

When this CachedRowSetReader object reads data into its rowset, it sets the field writerCalls to 0. When the writer associated with the rowset is called to write data back to the underlying data source, its writeData method calls the method CachedRowSetReader.reset, which increments writerCalls and returns true if writerCalls is 1. Thus, writerCalls equals 1 after the first call to writeData that occurs after the rowset has had data read into it.

Constructor Detail

CachedRowSetReader	back to summary
public CachedRowSetReader()

Method Detail

connect back to summary

connect	back to summary
public Connection connect(RowSetInternal caller) throws SQLException Establishes a connection with the data source for the given `RowSet` object. If the rowset's `dataSourceName` property has been set, this method uses the JNDI API to retrieve the `DataSource` object that it can use to make the connection. If the url, username, and password properties have been set, this method uses the `DriverManager.getConnection` method to make the connection. This method is used internally by the reader and writer associated with the calling `RowSet` object; an application never calls it directly. Parameters caller:RowSetInternal a `RowSet` object that has implemented the `RowSetInternal` interface and had this `CachedRowSetReader` object set as its reader Returns:Connection a `Connection` object that represents a connection to the caller's data source Exceptions SQLException: if an access error occurs

public Connection connect(RowSetInternal caller) throws SQLException

Establishes a connection with the data source for the given RowSet object. If the rowset's dataSourceName property has been set, this method uses the JNDI API to retrieve the DataSource object that it can use to make the connection. If the url, username, and password properties have been set, this method uses the DriverManager.getConnection method to make the connection.

This method is used internally by the reader and writer associated with the calling RowSet object; an application never calls it directly.

Parameters

caller:RowSetInternal: a RowSet object that has implemented the RowSetInternal interface and had this CachedRowSetReader object set as its reader

Returns:Connection

a Connection object that represents a connection to the caller's data source

Exceptions

SQLException:: if an access error occurs

decodeParams back to summary

decodeParams	back to summary
private void decodeParams(Object[] params, PreparedStatement pstmt) throws SQLException Sets the parameter placeholders in the rowset's command (the given `PreparedStatement` object) with the parameters in the given array. This method, called internally by the method `CachedRowSetReader.readData`, reads each parameter, and based on its type, determines the correct `PreparedStatement.setXXX` method to use for setting that parameter. Parameters params:Object[] an array of parameters to be used with the given `PreparedStatement` object pstmt:PreparedStatement the `PreparedStatement` object that is the command for the calling rowset and into which the given parameters are to be set Annotations @SuppressWarnings:deprecation Exceptions SQLException: if an access error occurs

private void decodeParams(Object[] params, PreparedStatement pstmt) throws SQLException

Sets the parameter placeholders in the rowset's command (the given PreparedStatement object) with the parameters in the given array. This method, called internally by the method CachedRowSetReader.readData, reads each parameter, and based on its type, determines the correct PreparedStatement.setXXX method to use for setting that parameter.

Parameters

params:Object[]: an array of parameters to be used with the given PreparedStatement object
pstmt:PreparedStatement: the PreparedStatement object that is the command for the calling rowset and into which the given parameters are to be set

Annotations

@SuppressWarnings:deprecation

Exceptions

SQLException:: if an access error occurs

getCloseConnection	back to summary
protected boolean getCloseConnection() Assists in determining whether the current connection was created by this CachedRowSet to ensure incorrect connections are not prematurely terminated. Returns:boolean a boolean giving the status of whether the connection has been closed.

getCloseConnection

back to summary

protected boolean getCloseConnection()

Assists in determining whether the current connection was created by this CachedRowSet to ensure incorrect connections are not prematurely terminated.

Returns:boolean: a boolean giving the status of whether the connection has been closed.

readData back to summary

readData	back to summary
public void readData(RowSetInternal caller) throws SQLException Implements javax.sql.RowSetReader.readData. Reads data from a data source and populates the given `RowSet` object with that data. This method is called by the rowset internally when the application invokes the method `execute` to read a new set of rows. After clearing the rowset of its contents, if any, and setting the number of writer calls to `0`, this reader calls its `connect` method to make a connection to the rowset's data source. Depending on which of the rowset's properties have been set, the `connect` method will use a `DataSource` object or the `DriverManager` facility to make a connection to the data source. Once the connection to the data source is made, this reader executes the query in the calling `CachedRowSet` object's `command` property. Then it calls the rowset's `populate` method, which reads data from the `ResultSet` object produced by executing the rowset's command. The rowset is then populated with this data. This method's final act is to close the connection it made, thus leaving the rowset disconnected from its data source. Parameters caller:RowSetInternal a `RowSet` object that has implemented the `RowSetInternal` interface and had this `CachedRowSetReader` object set as its reader Exceptions SQLException: if there is a database access error, there is a problem making the connection, or the command property has not been set

public void readData(RowSetInternal caller) throws SQLException

Implements javax.sql.RowSetReader.readData.

Reads data from a data source and populates the given RowSet object with that data. This method is called by the rowset internally when the application invokes the method execute to read a new set of rows.

After clearing the rowset of its contents, if any, and setting the number of writer calls to 0, this reader calls its connect method to make a connection to the rowset's data source. Depending on which of the rowset's properties have been set, the connect method will use a DataSource object or the DriverManager facility to make a connection to the data source.

Once the connection to the data source is made, this reader executes the query in the calling CachedRowSet object's command property. Then it calls the rowset's populate method, which reads data from the ResultSet object produced by executing the rowset's command. The rowset is then populated with this data.

This method's final act is to close the connection it made, thus leaving the rowset disconnected from its data source.

Parameters

caller:RowSetInternal: a RowSet object that has implemented the RowSetInternal interface and had this CachedRowSetReader object set as its reader

Exceptions

SQLException:: if there is a database access error, there is a problem making the connection, or the command property has not been set

readObject	back to summary
private void readObject(ObjectInputStream ois) throws IOException, ClassNotFoundException

reset back to summary

reset	back to summary
public boolean reset() throws SQLException Checks to see if the writer associated with this reader needs to reset its state. The writer will need to initialize its state if new contents have been read since the writer was last called. This method is called by the writer that was registered with this reader when components were being wired together. Returns:boolean `true` if writer associated with this reader needs to reset the values of its fields; `false` otherwise Exceptions SQLException: if an access error occurs

public boolean reset() throws SQLException

Checks to see if the writer associated with this reader needs to reset its state. The writer will need to initialize its state if new contents have been read since the writer was last called. This method is called by the writer that was registered with this reader when components were being wired together.

Returns:boolean

true if writer associated with this reader needs to reset the values of its fields; false otherwise

Exceptions

SQLException:: if an access error occurs

setStartPosition back to summary

setStartPosition	back to summary
public void setStartPosition(int pos) This sets the start position in the ResultSet from where to begin. This is called by the Reader in the CachedRowSetImpl to set the position on the page to begin populating from. Parameters pos:int integer indicating the position in the `ResultSet` to begin populating from.

public void setStartPosition(int pos)

This sets the start position in the ResultSet from where to begin. This is called by the Reader in the CachedRowSetImpl to set the position on the page to begin populating from.

Parameters

pos:int: integer indicating the position in the ResultSet to begin populating from.

public Class CachedRowSetReader

Field Summary

Constructor Summary

Method Summary

Field Detail

Constructor Detail

Method Detail