com.klg.jclass.datasource.jdbc
Class MetaData

java.lang.Object
  |
  +--javax.swing.tree.DefaultMutableTreeNode
        |
        +--com.klg.jclass.datasource.DataSourceTreeNode
              |
              +--com.klg.jclass.datasource.BaseMetaData
                    |
                    +--com.klg.jclass.datasource.jdbc.MetaData

All Implemented Interfaces:

Cloneable, MetaDataModel, MutableTreeNode, Serializable, TreeNode

public class MetaData

extends BaseMetaData

implements Serializable

This MetaData connects to a data source through JDBC. Each instance of this MetaData will have a particular query associated with it. This MetaData will execute that query and cache the results.

When used in the context of the JClass HiGrid, multiple result sets will be cached. These result sets will be based on the same query but with different parameters. When used in JClass HiGrid, this control will be a node in the MetaTree describing the relationships between SQL queries.

Transaction support is built on top of JDBC transactions. To turn on transaction support, "auto commit" must be disabled on the JDBC Connection which is passed into this object. Alternatively, calling setAutoCommit(false) on this MetaData object does the same. Since the same Connection can be shared among one or more MetaData objects calling MetaData.setAutoCommit(false) is redundant on all but the first.

Commits and rollbacks happen on a per Connection basis. If all MetaData objects share the same Connection, modifications spanning levels will be committed as group within one transaction. If multiple Connections objects are used however, say for example, one per MetaData object, RootMetaData.rollbackTransaction() will recurse and rollback transaction on all those MetaData objects which have not yet been successfully committed. If they have been committed, they are not rolledback and their changes are permanent. Those on which a successful commitTransaction has not occurred will be rolled back.

The default is to accept the JDBC default which is "auto commit" is "true". This means that unless the auto commit on the Connection is explicitly set to "false" (by calling setAutoCommit(false) on the Connection object directly or indirectly through MetaData.setAutoCommit(false), each statement will be commit upon completion.

See Also:

Serialized Form

Field Summary

static int	DEFAULT_DESIGN_TIME_MAX_ROWS
protected static int	designTimeMaxRows
protected String	driverTable The table which drives a row when there is more than one table for a row.
protected com.klg.jclass.datasource.jdbc.DataTableConnection	ds_connection Encapsulates JDBC connection.
protected Vector	join_columns These are the keys columns used by this control to link to its parent.
protected static int	NOT_FOUND
protected int	numColumns Number of colums for this ds.
protected boolean	open Returns true if this instance been initialized.
protected com.klg.jclass.datasource.jdbc.MetaData	parent_control This data control's parent.
protected com.klg.jclass.datasource.util.SqlParser	parser
protected com.klg.jclass.datasource.jdbc.PersistorModel	persistor Class responsible for saving changes to db
protected String	query The query statement is used to populate this DataTable
protected PreparedStatement	query_statement The JDBC version of the query.
protected Vector	tableColumnIndexes Vector of column indexes for a table.
protected Vector	tables Vector of database tables for this level.
protected Hashtable	tableToPrimaryKeyMap Primary keys.

Fields inherited from class com.klg.jclass.datasource.BaseMetaData

binding, bufferSize, cacheChildren, columns, commitPolicy, counter, currentBookmark, currentDataTable, dataModel, deletePermissions, description, idxToColumnMap, initialHashtableSize, insertPermissions, maxRows, metaDataID, provider, showDeletedRows, storeClass, updatePermissions

Fields inherited from class javax.swing.tree.DefaultMutableTreeNode

allowsChildren, children, EMPTY_ENUMERATION, parent, userObject

Fields inherited from interface com.klg.jclass.datasource.MetaDataModel

COMMIT_LEAVING_ANCESTOR, COMMIT_LEAVING_RECORD, COMMIT_MANUALLY, TYPE_BIG_DECIMAL, TYPE_BOOLEAN, TYPE_BYTE, TYPE_BYTE_ARRAY, TYPE_DOUBLE, TYPE_FLOAT, TYPE_INTEGER, TYPE_LONG, TYPE_OBJECT, TYPE_SHORT, TYPE_SQL_DATE, TYPE_SQL_TIME, TYPE_SQL_TIMESTAMP, TYPE_STRING, TYPE_UTIL_DATE

Constructor Summary

MetaData(com.klg.jclass.datasource.DataModel dataModel, com.klg.jclass.datasource.jdbc.DataTableConnection ds_connection)
General purpose MetaData Constructor.

MetaData(com.klg.jclass.datasource.DataModel dataModel, com.klg.jclass.datasource.jdbc.DataTableConnection ds_connection, String query)
Convenience root constructor.

MetaData(com.klg.jclass.datasource.DataModel dataModel, com.klg.jclass.datasource.jdbc.DataTableConnection ds_connection, String query, int maxRows)
Convenience root constructor which allows max rows to be set.

MetaData(com.klg.jclass.datasource.DataModel dataModel, com.klg.jclass.datasource.MetaDataModel parent, com.klg.jclass.datasource.jdbc.DataTableConnection ds_connection)
After first calling the Root constructor, call this to add master-detail relationships.

Method Summary

void	addColumn(com.klg.jclass.datasource.ColumnModel column) Adds a column to the list of column objects.
void	addColumnToIdentifiers(String column_name, int position) Adds the column to the internal mapping
void	clear() For internal use only.
void	commitTransaction() Recursivly Commits the transaction.
com.klg.jclass.datasource.jdbc.DataTable	executeQuery() Internal method, passes parent row to new DataTables.
com.klg.jclass.datasource.jdbc.DataTable	executeQuery(long parent_row) Execute the query.
protected void	finalize() Free any lingering jdbc resources.
boolean	getAutoCommit() Default implementation: returns true.
Vector	getColumnIndexesForTable(String table) Convenience method: returns this table's column indexes.
com.klg.jclass.datasource.jdbc.DataTableConnection	getDataTableConnection() Gets this data control's DataTableConnection.
static int	getDesignTimeMaxRows() Gets the maximum number of rows returned from a database at design-time.
String	getDriverTable() Returns the name of the table used to drive requeries when more than one table contributes columns to a row.
int	getDriverTableIndex() Returns the index of the driver table in the list of tables.
Vector	getJoinColumns() Return the list of join columns.
Object	getNativeMetaData() Return the native meta data object.
com.klg.jclass.datasource.util.SqlParser	getParser() Returns the parser of the sql query statement.
com.klg.jclass.datasource.jdbc.PersistorModel	getPersistor() Return the PersistorModel instance which is to be used to save changes to the data base.
String	getStatement() Return the current query statement.
Vector	getTables() Convenience method: returns the tables associated with this level.
String	getWhereClause() Return the current "where" clause used for getting data.
boolean	isOpen() Returns true if this MetaData object has been initialized.
boolean	isUpdateAllowedOnColumn(String column) Returns true if an update is allowed on this column.
void	joinOnParentColumn(String parentColumn, String childColumn) Adds a key column which will be used to join to this control's parent.
com.klg.jclass.datasource.jdbc.DataTable	open() Initializes by causing the ResultSetMetaData to be loaded.
void	rollbackTransaction() Recursivly rolls back the transaction.
void	setAutoCommit(boolean value) Sets the auto commit flag.
void	setColumnTableRelations(String table, String[] columnNames) Explicitly sets the relationships between tables and columns.
void	setConnection(com.klg.jclass.datasource.jdbc.DataTableConnection ds_connection) Sets this data control's connection to DataTableConnection.
static void	setDesignTimeMaxRows(int max) Sets the maximum number of rows returned from a database at design-time.
void	setDriverTable(String driverTable) Sets the name of the table whose primary key will be used to requery a row when more than one table contributes columns to a row.
void	setParameter(int number, Object value, int type) Sets a particular parameter in the sql statement.
void	setPersistor(String className) Sets the class which is to be used for saving data modifications back to the originating data base.
void	setPrimaryKeys(String table, String[] columnNames) Sets the primary keys for a table.
void	setStatement(String query) Set the SQL statement used to retrieve data.
void	setWhereClause(String whereClause) Change or add a where clause for the existing query statement.

Methods inherited from class com.klg.jclass.datasource.BaseMetaData

createByteArrayFromBinaryStream, getBinding, getBufferSize, getCacheChildren, getColumnCount, getColumnIdentifier, getColumnIndex, getColumnMap, getColumnObject, getColumnObjects, getCommitPolicy, getCurrentBookmark, getCurrentDataTable, getDataModel, getDeleteAllowed, getDescription, getInsertAllowed, getJavaColumnType, getMaxRows, getMetaID, getProvider, getShowDeletedRows, getStoreClass, getUpdateAllowed, setBinding, setBufferSize, setCacheChildren, setCommitPolicy, setCurrentBookmark, setCurrentDataTable, setDeleteAllowed, setDescription, setInsertAllowed, setMaxRows, setMetaID, setProviderClassName, setShowDeletedRows, setStoreClass, setUpdateAllowed

Methods inherited from class com.klg.jclass.datasource.DataSourceTreeNode

getChildren, getFirstChild, getIterator, getIterator, getIterator, getIterator, getLastChild, getNextChild, getPreviousChild, hasChildren, insert, isChildOf, toString

Methods inherited from class javax.swing.tree.DefaultMutableTreeNode

add, breadthFirstEnumeration, children, clone, depthFirstEnumeration, getAllowsChildren, getChildAfter, getChildAt, getChildBefore, getChildCount, getDepth, getFirstLeaf, getIndex, getLastLeaf, getLeafCount, getLevel, getNextLeaf, getNextNode, getNextSibling, getParent, getPath, getPathToRoot, getPreviousLeaf, getPreviousNode, getPreviousSibling, getRoot, getSharedAncestor, getSiblingCount, getUserObject, getUserObjectPath, insert, isLeaf, isNodeAncestor, isNodeChild, isNodeDescendant, isNodeRelated, isNodeSibling, isRoot, pathFromAncestorEnumeration, postorderEnumeration, preorderEnumeration, remove, remove, removeAllChildren, removeFromParent, setAllowsChildren, setParent, setUserObject

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface javax.swing.tree.TreeNode

children, getAllowsChildren, getChildAt, getChildCount, getIndex, getParent, isLeaf

Field Detail

DEFAULT_DESIGN_TIME_MAX_ROWS

public static final int DEFAULT_DESIGN_TIME_MAX_ROWS

See Also:

Constant Field Values

ds_connection

protected com.klg.jclass.datasource.jdbc.DataTableConnection ds_connection

Encapsulates JDBC connection.

query_statement

protected transient PreparedStatement query_statement

The JDBC version of the query.

numColumns

protected int numColumns

Number of colums for this ds.

tableToPrimaryKeyMap

protected Hashtable tableToPrimaryKeyMap

Primary keys.

Since:

JClass 4.0K for Java 2. If you are using JClass 4.0J, which is based on JDK 1.1, this field's or method's return type is based on the corresponding com.sun.java.util class.

parent_control

protected com.klg.jclass.datasource.jdbc.MetaData parent_control

This data control's parent.

join_columns

protected Vector join_columns

These are the keys columns used by this control to link to its parent.

tables

protected Vector tables

Vector of database tables for this level.

query

protected String query

The query statement is used to populate this DataTable

tableColumnIndexes

protected Vector tableColumnIndexes

Vector of column indexes for a table. The table is indexed by its own Vector.

open

protected boolean open

Returns true if this instance been initialized.

driverTable

protected String driverTable

The table which drives a row when there is more than one table for a row.

persistor

protected com.klg.jclass.datasource.jdbc.PersistorModel persistor

Class responsible for saving changes to db

parser

protected com.klg.jclass.datasource.util.SqlParser parser

designTimeMaxRows

protected static int designTimeMaxRows

NOT_FOUND

protected static int NOT_FOUND

Constructor Detail

MetaData

public MetaData(com.klg.jclass.datasource.DataModel dataModel,
                com.klg.jclass.datasource.jdbc.DataTableConnection ds_connection)

General purpose MetaData Constructor. Can be used as an alternate to the convenience root meta data constructor to, say, set query parameters on the root. For example,

     MetaData Orders = new MetaData(this, connection);
     Orders.setStatement("select * from Orders where OrderID < ?");
     Orders.setDescription("Orders");
     Orders.setParameter(1, new Integer(OrderIdParameter), java.sql.Types.INTEGER);
     Orders.setMaxRows(5);
     getMetaDataTree().setRoot(Orders);
     getDataTableTree().setRoot(Orders.executeQuery());
 

As this example shows, this constructor does not automatically add this MetaData object to the meta data tree as do the convenience constructors. It must be added manually. Since in this example we created the root-level node we must also manually set the root of the data table tree.

Your query must include all the primary key columns for each table in the select statement, otherwise update anomalies may occur.

Parameters:

dataModel - the DataModel

MetaData

public MetaData(com.klg.jclass.datasource.DataModel dataModel,
                com.klg.jclass.datasource.jdbc.DataTableConnection ds_connection,
                String query,
                int maxRows)
         throws DataModelException

Convenience root constructor which allows max rows to be set. Useful for design time where only a sampling of rows is required. Sets and executes the query to bootstrap root levels of the MetaDataTree and the DataTableTree. This constructor executes the query and sets the resulting DataTable as the root of the DataTableTree. Call this constructor first, then call the MetaData(DataTableConnection, DataModel, MetaData parent) to build the MetaDataTree hierarchy. Sets "open" to true.

Your query must include all the primary key columns for each table in the select statement, otherwise update anomalies may occur.

Parameters:

dataModel - the DataModel to which this meta data object will be added.

query - the String sql query the results of which will form the root level in the MetaDateTree.

maxRows - an int restricting the number of rows this query can return.

Throws:

DataModelException - If the operation fails.

MetaData

public MetaData(com.klg.jclass.datasource.DataModel dataModel,
                com.klg.jclass.datasource.jdbc.DataTableConnection ds_connection,
                String query)
         throws DataModelException

Convenience root constructor. Sets and executes the query to bootstrap root levels of the MetaDataTree and the DataTableTree. This constructor executes the query and sets the resulting DataTable as the root of the DataTableTree. Call this constructor first, then call the MetaData(DataTableConnection, DataModel, MetaData parent) to build the MetaDataTree hierarchy. Sets "open" to true.

Your query must include all the primary key columns for each table in the select statement, otherwise update anomalies may occur.

Parameters:

dataModel - the DataModel to which this meta data object will be added.

query - the String sql query the results of which will form the root level in the MetaDateTree.

Throws:

DataModelException - If the operation fails.

MetaData

public MetaData(com.klg.jclass.datasource.DataModel dataModel,
                com.klg.jclass.datasource.MetaDataModel parent,
                com.klg.jclass.datasource.jdbc.DataTableConnection ds_connection)

After first calling the Root constructor, call this to add master-detail relationships. After calling setStatement() and joinOnParentColumn(), you must call open().

Parameters:

dataModel - the HiGrid DataModel to which this meta data object will be added.

parent - the MetaData object which will be the master of this detail MetaData object.

Method Detail

setConnection

public void setConnection(com.klg.jclass.datasource.jdbc.DataTableConnection ds_connection)

Sets this data control's connection to DataTableConnection.

getDataTableConnection

public com.klg.jclass.datasource.jdbc.DataTableConnection getDataTableConnection()

Gets this data control's DataTableConnection.

Returns:

this data control's DataTableConnection

setStatement

public void setStatement(String query)
                  throws DataModelException

Set the SQL statement used to retrieve data. The statement can be a select statement or a call to stored procedure. For example, setStatement(" select * from products where id = ? ") or setStatement(" {call sp_product_info(?)} ") Note: the primary keys for each table involved in the select statement must be included in the columns selected.

Parameters:

query - a String, the SQL statement to be executed

Throws:

DataModelException - If set fails.

setWhereClause

public void setWhereClause(String whereClause)
                    throws DataModelException

Change or add a where clause for the existing query statement. After setting the query statement by calling setStatement() you can call this method to change (or add) the where clause of the existing statement. This allows you to dynamcially change the selection criteria at run-time.

If this is a child level, you must preserve the number and order of the join parameters (i.e. the order in which they were added by calls to the joinOnParentColumn method).

For example, if your original query was this:

  select * from OrderDetails where OrderID = ?"
 

calling setWhereClause("where OrderID = ? and ProductID = 'AMPB5'") results in this new query:

  select * from OrderDetails where OrderID = ? and ProductID = 'AMPB5'
 

Parameters:

whereClause - a String which is the new where clause

Throws:

DataModelException - If the set fails.

See Also:

joinOnParentColumn(java.lang.String, java.lang.String)

getWhereClause

public String getWhereClause()

Return the current "where" clause used for getting data. This is a convenience method. It calls getParser().getClause(SqlParser.WHERE).

Returns:

a String, the current where clause

See Also:

SqlParser

getStatement

public String getStatement()

Return the current query statement.

Returns:

a String, the current query statement for getting data

See Also:

setStatement(java.lang.String), setWhereClause(java.lang.String)

joinOnParentColumn

public void joinOnParentColumn(String parentColumn,
                               String childColumn)

Adds a key column which will be used to join to this control's parent. For composite keys (that is, tables are joined on more than one column), call this method once for each key column.

Parameters:

childColumn - a String indicating to which child column the parent column should match, required because parent column names can be different than child column names; if the column is aliased, used the alias, otherwise use the name as it appears in the select statement ([catalog.][schema.][table.]column.)

setParameter

public void setParameter(int number,
                         Object value,
                         int type)
                  throws DataModelException

Sets a particular parameter in the sql statement. Statement can be a SQL statement or a stored procedure. Sets the parameters by their position in the original statement.

Parameters:

number - an int indicating the position of the parameter, starts at 1.

value - the Object which is to be set

Throws:

DataModelException - If setParameter fails.

getTables

public Vector getTables()

Convenience method: returns the tables associated with this level. There can be one or many tables (related by one-to-one relationships) for a level.

Returns:

tables a Vector of tables for this level

getColumnIndexesForTable

public Vector getColumnIndexesForTable(String table)

Convenience method: returns this table's column indexes. Through calls to ResultSetMetaData.getTableName() or by explicitly calling setColumnTableRelationships() each Column object in the columns array has its table name property set. This method returns the ordinal positions of this table's columns in the row.

Parameters:

table - the String name of a table; if aliased, used the alias, otherwise use the table name as it appears in the select statement ([catalog.][schema.]table)

Returns:

a Vector of Integers which are the ordinal positions of this table's columns in the row.

executeQuery

public com.klg.jclass.datasource.jdbc.DataTable executeQuery()
                                                      throws DataModelException

Internal method, passes parent row to new DataTables.

Throws:

DataModelException - If executeQuery fails.

executeQuery

public com.klg.jclass.datasource.jdbc.DataTable executeQuery(long parent_row)
                                                      throws DataModelException

Execute the query. Builds a cached version of the result set data.

Returns:

a DataTable of the new results

Throws:

DataModelException - If executeQuery fails

addColumnToIdentifiers

public void addColumnToIdentifiers(String column_name,
                                   int position)
                            throws DataModelException

Adds the column to the internal mapping

Parameters:

column_name - a String which is the column alias or the column name as it appears in the select statement ([catalog.][schema.][table.]column)

Throws:

DataModelException - If the mapping fails.

See Also:

BaseMetaData.addColumn(com.klg.jclass.datasource.ColumnModel)

clear

public void clear()

Description copied from class: BaseMetaData

For internal use only. Changes the query for this data control. For customizer use during design-time.

Specified by:

clear in interface MetaDataModel

Overrides:

clear in class BaseMetaData

setPrimaryKeys

public void setPrimaryKeys(String table,
                           String[] columnNames)

Sets the primary keys for a table. If both JDBC methods getPrimaryKeys() and getBestRowIdentifier() fail to determine the primary keys for a table, you must explicitly set them by calling this method. An exception will be thrown when the primary keys cannot be determined automatically.

Parameters:

table - a String which is the table alias or table name as it appears in the select statement (([catalog.][schema.]table)

open

public com.klg.jclass.datasource.jdbc.DataTable open()
                                              throws DataModelException

Initializes by causing the ResultSetMetaData to be loaded. Does nothing if already open. Performs checks to see that the number of join_columns equals the number of question mark place holders. Also checks that for unique column names.

Throws:

DataModelException - If the operation fails.

setColumnTableRelations

public void setColumnTableRelations(String table,
                                    String[] columnNames)
                             throws DataModelException

Explicitly sets the relationships between tables and columns. If introspection fails to determine the association between tables and their columns (when there is more than one table to a level), or you wish to override the assocations, say to exculde a column in the update statement, use this method. This method must be called for each table. For example, if SalesOrder and Store are joined in a one-to-one relationship for a level, these would be the necessary calls. In this example the MetaData object is called Orders. Orders.setColumnTableRelations("SalesOrder", new String[] {"id","store_id","cust_id","ship_via","purchase_order_number","order_date","order_total"}); Orders.setColumnTableRelations("Store", new String[] {"store_store_id","address","phone_number","name"}); Or for a single table on a level the call would be, Customer.setColumnTableRelations("Customer", new String[] {"*"}); The "*" means all columns are from the Customer table.

Parameters:

table - a String, the name to which (a subset of the columns belong); use the table name as it appears in the FROM clause; don't use alias

Throws:

DataModelException - If the operation fails.

isOpen

public boolean isOpen()

Returns true if this MetaData object has been initialized.

Returns:

true if this MetaData object has been opened, false otherwise.

See Also:

open

setDriverTable

public void setDriverTable(String driverTable)

Sets the name of the table whose primary key will be used to requery a row when more than one table contributes columns to a row. The default is to use the first table in the list of tables. The driver table is the table whose primary key is used to requery the row, the other tables join to this table.

Parameters:

driverTable - a String, the table alias or name as it appears in the select statement ([catalog.][schema.]table)

getDriverTable

public String getDriverTable()

Returns the name of the table used to drive requeries when more than one table contributes columns to a row. The driver table is the table whose primary key is used to requery the row, the other tables join to this table.

Returns:

a String which is the driver table name.

getDriverTableIndex

public int getDriverTableIndex()

Returns the index of the driver table in the list of tables. Default is to use the first table. The driver table is the table whose primary key is used to requery the row, the other tables join to this table.

Returns:

an int which is the index of the driver table in the tables list.

setAutoCommit

public void setAutoCommit(boolean value)
                   throws DataModelException

Sets the auto commit flag. If the underlying data source supports transactions and this flag is set to false, a transaction will wrap data modifications. The default is to not attempt to wrap modifications in a transaction.

Specified by:

setAutoCommit in interface MetaDataModel

Overrides:

setAutoCommit in class BaseMetaData

Throws:

DataModelException - If the operation fails.

getAutoCommit

public boolean getAutoCommit()
                      throws DataModelException

Default implementation: returns true. Must be overridden in specific implementations if transactions are supported and enabled. Return true if the transaction capabilities of the underlying data source are to be used when saving modifications (transactions are supported and enabled). If the underlying data source supports transactions and this capability has been enabled, data modifications will be wrapped in a transaction which can be committed or rolled back.

Specified by:

getAutoCommit in interface MetaDataModel

Overrides:

getAutoCommit in class BaseMetaData

Throws:

DataModelException - If the operation fails.

See Also:

commitTransaction(), rollbackTransaction()

rollbackTransaction

public void rollbackTransaction()
                         throws DataModelException

Recursivly rolls back the transaction. If the underlying data source supports transactions and transactions have been enabled, calling this method will roll back all pending transactions on the data source, otherwise it does nothing.

Specified by:

rollbackTransaction in interface MetaDataModel

Overrides:

rollbackTransaction in class BaseMetaData

Throws:

DataModelException - If rollback fails.

See Also:

MetaDataModel.getAutoCommit()

commitTransaction

public void commitTransaction()
                       throws DataModelException

Recursivly Commits the transaction. If the underlying data source supports transactions and transactions have been enabled, calling this method will commit all pending transactions on the data source, otherwise it does nothing.

Specified by:

commitTransaction in interface MetaDataModel

Overrides:

commitTransaction in class BaseMetaData

Throws:

DataModelException - If commit fails.

See Also:

MetaDataModel.getAutoCommit()

isUpdateAllowedOnColumn

public boolean isUpdateAllowedOnColumn(String column)
                                throws DataModelException

Returns true if an update is allowed on this column.

Specified by:

isUpdateAllowedOnColumn in interface MetaDataModel

Overrides:

isUpdateAllowedOnColumn in class BaseMetaData

Returns:

true if updates are allowed (by the data model) on this column

Throws:

DataModelException - If primary keys not found.

See Also:

BaseMetaData.getUpdateAllowed(java.lang.String), BaseMetaData.setUpdateAllowed(java.lang.String, boolean)

getParser

public com.klg.jclass.datasource.util.SqlParser getParser()

Returns the parser of the sql query statement. From this you can get the SELECT, FROM, and WHERE clauses of the statement.

Returns:

the parser of the current sql query statement

See Also:

SqlParser

addColumn

public void addColumn(com.klg.jclass.datasource.ColumnModel column)
               throws DataModelException

Adds a column to the list of column objects. Overrides BaseMetaData method of same name.

Specified by:

addColumn in interface MetaDataModel

Overrides:

addColumn in class BaseMetaData

Throws:

DataModelException - If column add fails.

See Also:

BaseMetaData.addColumn(com.klg.jclass.datasource.ColumnModel)

getNativeMetaData

public Object getNativeMetaData()

Return the native meta data object. This is a DataSet in JBuilder and a RelationView in VisualCafe.

Specified by:

getNativeMetaData in interface MetaDataModel

Overrides:

getNativeMetaData in class BaseMetaData

Returns:

this.

setPersistor

public void setPersistor(String className)
                  throws DataModelException

Sets the class which is to be used for saving data modifications back to the originating data base. This class must implement the PersistorModel interface. The default behavior is to use the com.klg.jclass.datasource.jdbc.Persistor class.

Parameters:

className - the name of the class on which a Class.forName(className).newInstance will be done

Throws:

DataModelException - If loading the class fails.

getPersistor

public com.klg.jclass.datasource.jdbc.PersistorModel getPersistor()

Return the PersistorModel instance which is to be used to save changes to the data base.

Returns:

PersistorModel

See Also:

setPersistor(java.lang.String)

setDesignTimeMaxRows

public static void setDesignTimeMaxRows(int max)

Sets the maximum number of rows returned from a database at design-time. It is used to improve the performance at design-time. It has no effect at run-time. (default: 10)

See Also:

Beans.isDesignTime()

getDesignTimeMaxRows

public static int getDesignTimeMaxRows()

Gets the maximum number of rows returned from a database at design-time.

See Also:

setDesignTimeMaxRows(int)

getJoinColumns

public Vector getJoinColumns()

Return the list of join columns.

finalize

protected void finalize()

Free any lingering jdbc resources.

Overrides:

finalize in class Object