java.lang.Object
- org.apache.derby.impl.tools.planexporter.AccessDatabase

```
public class AccessDatabase
extends java.lang.Object
```
This class will perform the database connection establishment, querying the database, shut downing the database. Created under DERBY-4587-PlanExporter tool

Field Summary

Fields
Modifier and Type	Field	Description
`private java.sql.Connection`	`conn`
`private TreeNode[]`	`data`
`private int`	`depth`
`private static int`	`ID`
`private static int`	`INPUT_ROWS`
`private static int`	`NEXT_QUALIFIERS`
`private static int`	`NO_OF_OPENS`
`private static int`	`NO_OF_OUTPUT_ROWS_BY_SORTER`
`private static int`	`NODE_TYPE`
`private static int`	`P_ID`
`private java.lang.String`	`query`
`private static int`	`RETURNED_ROWS`
`private static int`	`SCAN_QUALIFIERS`
`private static int`	`SCAN_TYPE`
`private static int`	`SCANNED_OBJECT`
`private java.lang.String`	`schema`
`private boolean`	`schemaExists`
`private static int`	`SORT_TYPE`
`private static int`	`VISITED_PAGES`
`private java.lang.String`	`xmlDetails`

Constructor Summary

Constructors
Constructor	Description
`AccessDatabase(java.lang.String dburl, java.lang.String aSchema, java.lang.String aQuery)`
`AccessDatabase(java.sql.Connection aConn, java.lang.String aSchema, java.lang.String aQuery)`

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`void`	`closeConnection()`	closing the connection to the database
`private static java.sql.Connection`	`createConnection(java.lang.String dbURL)`
`private void`	`createXMLData(java.lang.String qry, int x)`	Create XML data based on the query that's passed in.
`void`	`createXMLFragment()`	This method creates the queries such that after execution of the query it will return XML data fragments.
`private static java.lang.String`	`escapeForXML(java.lang.String text)`	Escape characters that have a special meaning in XML.
`private java.lang.String`	`escapeInAttribute(java.lang.String text)`	This method is needed since in the case of XML attributes we have to filter the quotation (") marks that is compulsory.
`private void`	`findChildren(int idx, int dep)`
`private void`	`getChildren(int currentLevel, java.lang.String id)`
`TreeNode[]`	`getData()`
`int`	`getDepth()`
`java.lang.String`	`getQuery()`
`java.lang.String`	`getXmlString()`	Generating the XML tree
`java.lang.String`	`indent(int j)`
`boolean`	`initializeDataArray()`
`void`	`markTheDepth()`	marking the depth of each element
`private int`	`noOfNodes()`
`private boolean`	`schemaExists()`	Check if there is a schema in the database that matches the schema name that was passed in to this instance.
`private void`	`setSchema()`	Set the schema of the current connection to the XPLAIN schema in which the statistics can be found.
`java.lang.String`	`statement()`
`java.lang.String`	`stmtID()`
`java.lang.String`	`time()`
`boolean`	`verifySchemaExistance()`

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

conn
```
private final java.sql.Connection conn
```

schema
```
private final java.lang.String schema
```

query
```
private final java.lang.String query
```

schemaExists
```
private final boolean schemaExists
```

data
```
private TreeNode[] data
```

depth
```
private int depth
```

xmlDetails
```
private java.lang.String xmlDetails
```

ID
```
private static final int ID
```
See Also:

Constant Field Values

P_ID
```
private static final int P_ID
```
See Also:

Constant Field Values

NODE_TYPE
```
private static final int NODE_TYPE
```
See Also:

Constant Field Values

NO_OF_OPENS
```
private static final int NO_OF_OPENS
```
See Also:

Constant Field Values

INPUT_ROWS
```
private static final int INPUT_ROWS
```
See Also:

Constant Field Values

RETURNED_ROWS
```
private static final int RETURNED_ROWS
```
See Also:

Constant Field Values

VISITED_PAGES
```
private static final int VISITED_PAGES
```
See Also:

Constant Field Values

SCAN_QUALIFIERS
```
private static final int SCAN_QUALIFIERS
```
See Also:

Constant Field Values

NEXT_QUALIFIERS
```
private static final int NEXT_QUALIFIERS
```
See Also:

Constant Field Values

SCANNED_OBJECT
```
private static final int SCANNED_OBJECT
```
See Also:

Constant Field Values

SCAN_TYPE
```
private static final int SCAN_TYPE
```
See Also:

Constant Field Values

SORT_TYPE
```
private static final int SORT_TYPE
```
See Also:

Constant Field Values

NO_OF_OUTPUT_ROWS_BY_SORTER
```
private static final int NO_OF_OUTPUT_ROWS_BY_SORTER
```
See Also:

Constant Field Values

Constructor Detail

AccessDatabase

public AccessDatabase(java.lang.String dburl,
                      java.lang.String aSchema,
                      java.lang.String aQuery)
               throws java.lang.InstantiationException,
                      java.lang.IllegalAccessException,
                      java.lang.ClassNotFoundException,
                      java.sql.SQLException,
                      java.lang.NoSuchMethodException,
                      java.lang.reflect.InvocationTargetException

Parameters:: dburl -; aSchema -; aQuery -
Throws:: java.lang.InstantiationException; java.lang.IllegalAccessException; java.lang.ClassNotFoundException; java.sql.SQLException; java.lang.NoSuchMethodException; java.lang.reflect.InvocationTargetException

AccessDatabase

public AccessDatabase(java.sql.Connection aConn,
                      java.lang.String aSchema,
                      java.lang.String aQuery)
               throws java.sql.SQLException

Parameters:: aConn -; aSchema -; aQuery -
Throws:: java.sql.SQLException

Method Detail
- getQuery
```
public java.lang.String getQuery()
```
  Returns:
  
  the stmt_id
- getDepth
```
public int getDepth()
```
- createConnection
```
private static java.sql.Connection createConnection(java.lang.String dbURL)
                                             throws java.lang.InstantiationException,
                                                    java.lang.IllegalAccessException,
                                                    java.lang.ClassNotFoundException,
                                                    java.sql.SQLException,
                                                    java.lang.NoSuchMethodException,
                                                    java.lang.reflect.InvocationTargetException
```
  Throws:
  
  java.lang.InstantiationException
  
  java.lang.IllegalAccessException
  
  java.lang.ClassNotFoundException
  
  java.sql.SQLException
  
  java.lang.NoSuchMethodException
  
  java.lang.reflect.InvocationTargetException
- setSchema
```
private void setSchema()
                throws java.sql.SQLException
```
  Set the schema of the current connection to the XPLAIN schema in which the statistics can be found.
  
  Throws:
  
  java.sql.SQLException - if an error happens while accessing the database
- schemaExists
```
private boolean schemaExists()
                      throws java.sql.SQLException
```
  Check if there is a schema in the database that matches the schema name that was passed in to this instance.
  
  Throws:
  
  java.sql.SQLException
- verifySchemaExistance
```
public boolean verifySchemaExistance()
```
- createXMLFragment
```
public void createXMLFragment()
                       throws java.sql.SQLException
```
  This method creates the queries such that after execution of the query it will return XML data fragments.
  
  Throws:
  
  java.sql.SQLException
- getXmlString
```
public java.lang.String getXmlString()
```
  Generating the XML tree
  
  Returns:
  
  all xml elements as a String
- getChildren
```
private void getChildren(int currentLevel,
                         java.lang.String id)
```
  Parameters:
  
  currentLevel - level of the XML tree (0 based) of current node
  
  id - current node's stmt_id
- indent
```
public java.lang.String indent(int j)
```
  Parameters:
  
  j - indent needed
  
  Returns:
  
  indent as a string
- markTheDepth
```
public void markTheDepth()
```
  marking the depth of each element
- findChildren
```
private void findChildren(int idx,
                          int dep)
```
  Parameters:
  
  idx - current element's index
  
  dep - current examining depth
- initializeDataArray
```
public boolean initializeDataArray()
                            throws java.sql.SQLException
```
  Returns:
  
  whether the initialization is successful or not
  
  Throws:
  
  java.sql.SQLException
- createXMLData
```
private void createXMLData(java.lang.String qry,
                           int x)
                    throws java.sql.SQLException
```
  Create XML data based on the query that's passed in. The query should have exactly one parameter, which will be initialized to the statement id before the query is executed.
  
  Parameters:
  
  qry - query to be executed
  
  Throws:
  
  java.sql.SQLException
- noOfNodes
```
private int noOfNodes()
               throws java.sql.SQLException
```
  Returns:
  
  total # of nodes
  
  Throws:
  
  java.sql.SQLException
- statement
```
public java.lang.String statement()
                           throws java.sql.SQLException
```
  Returns:
  
  the <statement> element
  
  Throws:
  
  java.sql.SQLException
- escapeForXML
```
private static java.lang.String escapeForXML(java.lang.String text)
```
  Escape characters that have a special meaning in XML.
  
  Parameters:
  
  text - the text to escape
  
  Returns:
  
  the text with special characters escaped
- escapeInAttribute
```
private java.lang.String escapeInAttribute(java.lang.String text)
```
  This method is needed since in the case of XML attributes we have to filter the quotation (") marks that is compulsory. eg: scanned_object="A "quoted" table name";
  
  Parameters:
  
  text - attribute string to be checked
  
  Returns:
  
  modified string
- time
```
public java.lang.String time()
                      throws java.sql.SQLException
```
  Returns:
  
  XPLAIN_TIME of SYSXPLAIN_STATEMENTS
  
  Throws:
  
  java.sql.SQLException
- stmtID
```
public java.lang.String stmtID()
```
  Returns:
  
  stmt_id as a XML element
- closeConnection
```
public void closeConnection()
```
  closing the connection to the database
- getData
```
public TreeNode[] getData()
```
  Returns:
  
  data array of TreeNode Objects

Class AccessDatabase

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

conn

schema

query

schemaExists

data

depth

xmlDetails

ID

P_ID

NODE_TYPE

NO_OF_OPENS

INPUT_ROWS

RETURNED_ROWS

VISITED_PAGES

SCAN_QUALIFIERS

NEXT_QUALIFIERS

SCANNED_OBJECT

SCAN_TYPE

SORT_TYPE

NO_OF_OUTPUT_ROWS_BY_SORTER

Constructor Detail

AccessDatabase

AccessDatabase

Method Detail

getQuery

getDepth

createConnection

setSchema

schemaExists

verifySchemaExistance

createXMLFragment

getXmlString

getChildren

indent

markTheDepth

findChildren

initializeDataArray

createXMLData

noOfNodes

statement

escapeForXML

escapeInAttribute

time

stmtID

closeConnection

getData