org.objectweb.cjdbc.common.sql
Class SelectRequest

java.lang.Object
  org.objectweb.cjdbc.common.sql.AbstractRequest
      org.objectweb.cjdbc.common.sql.SelectRequest

All Implemented Interfaces:

java.io.Serializable

public class SelectRequest

extends AbstractRequest

implements java.io.Serializable

A SelectRequest is an SQL request of the following syntax:

  SELECT [ALL|DISTINCT] select-item[,select-item]* 
  FROM table-specification[,table-specification]* 
  [WHERE search-condition] 
  [GROUP BY grouping-column[,grouping-column]] 
  [HAVING search-condition] 
  [ORDER BY sort-specification[,sort-specification]] 
  [LIMIT ignored]
 

Note that table-specification in the FROM clause can be a sub-select. Everything after the end of the WHERE clause is ignored.

Version:

1.0

Author:

Emmanuel Cecchet , Julie Marguerite , Mathieu Peltier , Sara Bouchenak

See Also:

Serialized Form

Field Summary

private java.util.ArrayList	aliasFrom ArrayList of AliasedTable objects
static int	AVERAGE_FUNCTION Represents a SQL average() macro
static int	COUNT_FUNCTION Represents a SQL count() macro
private java.util.ArrayList	from ArrayList of String objects.
int	funcType Need to keep track of type of query, e.g.
static int	MAX_FUNCTION Represents a SQL max() macro
static int	MIN_FUNCTION Represents a SQL min() macro
static int	NO_FUNCTION Some values to keep track of function in the SELECT request
private java.util.ArrayList	order ArrayList of OrderBy objects
private java.lang.String	pkValue Primary key value in case of a unique selection
private java.util.ArrayList	select ArrayList of TableColumn objects.
private static long	serialVersionUID
static int	SUM_FUNCTION Represents a SQL sum() macro
private java.util.ArrayList	where ArrayList of TableColumn objects.
private java.util.Hashtable	whereValues Hashtable of String keys corresponding to column names and String values corresponding to the values associated with the UNIQUE columns of a UNIQUE SELECT.

Fields inherited from class org.objectweb.cjdbc.common.sql.AbstractRequest

cacheable, cursorName, escapeProcessing, fetchSize, id, isAutoCommit, isParsed, isReadOnly, login, maxRows, requestType, sqlQuery, sqlSkeleton, timeoutInSeconds, transactionId, transactionIsolation

Constructor Summary

SelectRequest(CJDBCInputStream in)

SelectRequest(java.lang.String sqlQuery, boolean escapeProcessing, int timeout, java.lang.String lineSeparator)
Creates a new SelectRequest instance.

SelectRequest(java.lang.String sqlQuery, boolean escapeProcessing, int timeout, java.lang.String lineSeparator, DatabaseSchema schema, int granularity, boolean isCaseSensitive)
Creates a new SelectRequest instance.

Method Summary

void	cloneParsing(AbstractRequest request) Clones the parsing of a request.
void	debug() Displays some debugging information about this request.
java.util.ArrayList	getAliasedFrom() Returns an ArrayList of AliasedDatabaseTable objects representing the table names found in the FROM clause of this request.
java.util.ArrayList	getFrom() Returns an ArrayList of String objects representing the table names found in the FROM clause of this request.
private java.util.ArrayList	getFromTables(java.lang.String fromClause, DatabaseSchema schema, boolean isCaseSensitive) Extracts the tables from the given FROM clause and retrieves their alias if any.
java.util.ArrayList	getOrderBy() Returns an ArrayList of OrderBy objects representing the columns involved in the ORDER BY clause of this request.
java.lang.String	getPkValue()
java.util.ArrayList	getSelect() Returns an ArrayList of DatabaseColumn objects representing the columns selected in the SELECT clause of this request.
private java.util.ArrayList	getSelectedColumns(java.lang.String selectClause, java.util.ArrayList aliasedFrom, boolean isCaseSensitive) Gets all the columns selected in the given SELECT clause.
java.util.ArrayList	getWhere() Returns an ArrayList of TableColumn objects representing the columns involved in the WHERE clause of this request.
private java.util.ArrayList	getWhereColumns(java.lang.String whereClause, java.util.ArrayList aliasedFrom, boolean setUniqueCacheable, boolean isCaseSensitive) Gets all the columns involved in the given WHERE clause.
java.util.Hashtable	getWhereValues() Returns an Hashtable of String keys representing unique column names and String values associated with the columns involved in this request.
private boolean	isSqlFunction(java.lang.String str) Checks if the string parameter represents an SQL function, e. g., MAX, COUNT, SUM, etc.
boolean	needsMacroProcessing() Returns true if this request requires macro (RAND(), NOW(), ...) processing.
void	parse(DatabaseSchema schema, int granularity, boolean isCaseSensitive) The result of the parsing is accessible through the getSelect(), getFrom()and getWhere()functions.
boolean	returnsResultSet() Does this request returns a ResultSet?
void	sendToStream(CJDBCOutputStream out, boolean needSqlSkeleton) Serialize the request on the output stream by sending only the needed parameters to reconstruct it on the controller.
void	setPkValue(java.lang.String pkValue)

Methods inherited from class org.objectweb.cjdbc.common.sql.AbstractRequest

equals, getCacheAbility, getCursorName, getEscapeProcessing, getFetchSize, getId, getLineSeparator, getLogin, getMaxRows, getSQL, getSQLShortForm, getSqlSkeleton, getTimeout, getTransactionId, getTransactionIsolation, isAlter, isAutoCommit, isCreate, isDDL, isDelete, isDML, isDriverProcessed, isDrop, isInsert, isParsed, isReadOnly, isSelect, isUpdate, receiveResultSetParams, sendResultSetParams, setCacheAbility, setCursorName, setDriverProcessed, setFetchSize, setId, setIsAutoCommit, setIsReadOnly, setLogin, setMaxRows, setSQL, setSqlSkeleton, setTimeout, setTransactionId, setTransactionIsolation, trimCarriageReturnAndTabs

Methods inherited from class java.lang.Object

clone, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

serialVersionUID

private static final long serialVersionUID

See Also:

Constant Field Values

select

private transient java.util.ArrayList select

ArrayList of TableColumn objects.

from

private transient java.util.ArrayList from

ArrayList of String objects.

aliasFrom

private transient java.util.ArrayList aliasFrom

ArrayList of AliasedTable objects

where

private transient java.util.ArrayList where

ArrayList of TableColumn objects.

order

private transient java.util.ArrayList order

ArrayList of OrderBy objects

NO_FUNCTION

public static final int NO_FUNCTION

Some values to keep track of function in the SELECT request

See Also:

Constant Field Values

MAX_FUNCTION

public static final int MAX_FUNCTION

Represents a SQL max() macro

See Also:

Constant Field Values

MIN_FUNCTION

public static final int MIN_FUNCTION

Represents a SQL min() macro

See Also:

Constant Field Values

AVERAGE_FUNCTION

public static final int AVERAGE_FUNCTION

Represents a SQL average() macro

See Also:

Constant Field Values

COUNT_FUNCTION

public static final int COUNT_FUNCTION

Represents a SQL count() macro

See Also:

Constant Field Values

SUM_FUNCTION

public static final int SUM_FUNCTION

Represents a SQL sum() macro

See Also:

Constant Field Values

funcType

public transient int funcType

Need to keep track of type of query, e.g. MAX, COUNT, etc.

pkValue

private transient java.lang.String pkValue

Primary key value in case of a unique selection

whereValues

private transient java.util.Hashtable whereValues

Hashtable of String keys corresponding to column names and String values corresponding to the values associated with the UNIQUE columns of a UNIQUE SELECT.

Used with the COLUMN_UNIQUE_DELETE granularity.

See Also:

CachingGranularities

Constructor Detail

SelectRequest

public SelectRequest(java.lang.String sqlQuery,
                     boolean escapeProcessing,
                     int timeout,
                     java.lang.String lineSeparator,
                     DatabaseSchema schema,
                     int granularity,
                     boolean isCaseSensitive)
              throws java.sql.SQLException

Creates a new SelectRequest instance. The caller must give an SQL request, without any leading or trailing spaces and beginning with 'select ' (it will not be checked).

The SQL request is parsed and selected tables and columns are retrieved using the given DatabaseSchema.

If the syntax is incorrect an exception is thrown.

Parameters:

sqlQuery - the SQL query

escapeProcessing - should the driver to escape processing before sending to the database ?

timeout - an int value

lineSeparator - the line separator used in the query

schema - a DatabaseSchema value

granularity - parsing granularity as defined in ParsingGranularities

isCaseSensitive - true if parsing is case sensitive

Throws:

java.sql.SQLException - if an error occurs

SelectRequest

public SelectRequest(java.lang.String sqlQuery,
                     boolean escapeProcessing,
                     int timeout,
                     java.lang.String lineSeparator)

Creates a new SelectRequest instance. The caller must give an SQL request, without any leading or trailing spaces and beginning with the 'select' keyword (it will not be checked).

The request is not parsed but it can be done later by a call to parse(DatabaseSchema, int, boolean).

Parameters:

sqlQuery - the SQL query

escapeProcessing - should the driver to escape processing before sending to the database ?

timeout - an int value

lineSeparator - the line separator used in the query

See Also:

parse(org.objectweb.cjdbc.common.sql.schema.DatabaseSchema, int, boolean)

SelectRequest

public SelectRequest(CJDBCInputStream in)
              throws java.io.IOException

See Also:

AbstractRequest.AbstractRequest(CJDBCInputStream, int)

Method Detail

sendToStream

public void sendToStream(CJDBCOutputStream out,
                         boolean needSqlSkeleton)
                  throws java.io.IOException

Description copied from class: AbstractRequest

Serialize the request on the output stream by sending only the needed parameters to reconstruct it on the controller. Has to mirror the deserialization method above.

Overrides:

sendToStream in class AbstractRequest

Parameters:

out - destination CJDBCOutputStream

needSqlSkeleton - true if controller wants SQL templates

Throws:

java.io.IOException - if fails

See Also:

AbstractRequest

parse

public void parse(DatabaseSchema schema,
                  int granularity,
                  boolean isCaseSensitive)
           throws java.sql.SQLException

The result of the parsing is accessible through the getSelect(), getFrom()and getWhere()functions.

Specified by:

parse in class AbstractRequest

Parameters:

schema - a DatabaseSchema value

granularity - parsing granularity as defined in ParsingGranularities

isCaseSensitive - true if parsing must be case sensitive

Throws:

java.sql.SQLException - if the parsing fails

See Also:

AbstractRequest.parse(org.objectweb.cjdbc.common.sql.schema.DatabaseSchema, int, boolean)

cloneParsing

public void cloneParsing(AbstractRequest request)

Description copied from class: AbstractRequest

Clones the parsing of a request.

Specified by:

cloneParsing in class AbstractRequest

Parameters:

request - the parsed request to clone

See Also:

AbstractRequest.cloneParsing(AbstractRequest)

getFromTables

private java.util.ArrayList getFromTables(java.lang.String fromClause,
                                          DatabaseSchema schema,
                                          boolean isCaseSensitive)
                                   throws java.sql.SQLException

Extracts the tables from the given FROM clause and retrieves their alias if any.

Parameters:

fromClause - the FROM clause of the request (without the FROM keyword)

schema - the DatabaseSchema this request refers to

isCaseSensitive - true if table name parsing is case sensitive

Returns:

an ArrayList of AliasedDatabaseTable objects

Throws:

java.sql.SQLException - if an error occurs

getSelectedColumns

private java.util.ArrayList getSelectedColumns(java.lang.String selectClause,
                                               java.util.ArrayList aliasedFrom,
                                               boolean isCaseSensitive)

Gets all the columns selected in the given SELECT clause.

The selected columns or tables must be found in the given ArrayList of AliasedDatabaseTable representing the FROM clause of the same request.

Parameters:

selectClause - SELECT clause of the request (without the SELECT keyword)

aliasedFrom - an ArrayList of AliasedDatabaseTable

isCaseSensitive - true if column name parsing is case sensitive

Returns:

an ArrayList of TableColumn

isSqlFunction

private boolean isSqlFunction(java.lang.String str)

Checks if the string parameter represents an SQL function, e. g., MAX, COUNT, SUM, etc.

Parameters:

str - A lower-case string that may represent an SQL function

Returns:

boolean true if it is an SQL function and false otherwise.

getWhereColumns

private java.util.ArrayList getWhereColumns(java.lang.String whereClause,
                                            java.util.ArrayList aliasedFrom,
                                            boolean setUniqueCacheable,
                                            boolean isCaseSensitive)

Gets all the columns involved in the given WHERE clause.

The selected columns or tables must be found in the given ArrayList of AliasedDatabaseTable representing the FROM clause of the same request.

Parameters:

whereClause - WHERE clause of the request (without the WHERE keyword)

aliasedFrom - an ArrayList of AliasedDatabaseTable

setUniqueCacheable - true if we have to check is this select is UNIQUE or not

isCaseSensitive - true if column name parsing is case sensitive

Returns:

an ArrayList of TableColumn

getSelect

public java.util.ArrayList getSelect()

Returns an ArrayList of DatabaseColumn objects representing the columns selected in the SELECT clause of this request.

Returns:

an ArrayList of TableColumn

getFrom

public java.util.ArrayList getFrom()

Returns an ArrayList of String objects representing the table names found in the FROM clause of this request.

Returns:

an ArrayList of String

getAliasedFrom

public java.util.ArrayList getAliasedFrom()

Returns an ArrayList of AliasedDatabaseTable objects representing the table names found in the FROM clause of this request.

Returns:

an ArrayList of AliasedDatabaseTable

getWhere

public java.util.ArrayList getWhere()

Returns an ArrayList of TableColumn objects representing the columns involved in the WHERE clause of this request.

Returns:

an ArrayList of TableColumn

getOrderBy

public java.util.ArrayList getOrderBy()

Returns an ArrayList of OrderBy objects representing the columns involved in the ORDER BY clause of this request.

Returns:

an ArrayList of OrderBy

getWhereValues

public java.util.Hashtable getWhereValues()

Returns an Hashtable of String keys representing unique column names and String values associated with the columns involved in this request.

Returns:

an Hashtable value

needsMacroProcessing

public boolean needsMacroProcessing()

Description copied from class: AbstractRequest

Returns true if this request requires macro (RAND(), NOW(), ...) processing.

Specified by:

needsMacroProcessing in class AbstractRequest

Returns:

true

See Also:

AbstractRequest.needsMacroProcessing()

returnsResultSet

public boolean returnsResultSet()

Description copied from class: AbstractRequest

Does this request returns a ResultSet?

Specified by:

returnsResultSet in class AbstractRequest

Returns:

true is this request will return a ResultSet

See Also:

AbstractRequest.returnsResultSet()

getPkValue

public java.lang.String getPkValue()

Returns:

Returns the pkValue.

setPkValue

public void setPkValue(java.lang.String pkValue)

Parameters:

pkValue - The pkValue to set.

debug

public void debug()

Displays some debugging information about this request.

Overrides:

debug in class AbstractRequest