com.jdc.rdb.sql
Class SQLHelper

java.lang.Object
  |
  +--com.jdc.lang.Object
        |
        +--com.jdc.rdb.sql.SQLHelper

All Implemented Interfaces:

Serializable

public class SQLHelper

extends Object

implements Serializable

SQLHelper is a utility class that provides Structured Query Language (SQL) helper methods to simplify the creation of Table command statements. The following methods are available:

• Create a qualified Table alias.
• Format a Table Column value.

Version:

1.0

Author:

Jay Damon

See Also:

SQLClauseHelper, Serialized Form

Field Summary

static String	COMMA The SQL statement comma character.
static String	EQUALS The SQL statement equals character.
protected static String	LEFT_PARENTHESIS The SQL statement left parenthesis character.
static String	NULL The SQL statement null keyword.
protected static String	RIGHT_PARENTHESIS The SQL statement right parenthesis character.
static String	SPACE The SQL statement space character.
protected static String	SUBSTITUTION_VALUE The SQL statement substitution value character.

Fields inherited from class com.jdc.lang.Object

string

Constructor Summary

SQLHelper()
Constructs a new SQLHelper object.

Method Summary

String	addCommas(String[] sqlClauseItems) Adds commas to SQL list items and return a comma-delimited SQL clause.
String	addDoubleQuotes(String sqlString) Adds double quotes to the SQL string, if the SQL string is not already contained in double quotes.
String	addParentheses(String sqlString) Adds parentheses to an SQL clause, if the SQL clause is not already contained in parentheses.
String	addSingleQuotes(String sqlString) Adds single quotes to the SQL string, if the SQL string is not already contained in single quotes.
String	createNameValues(String[] columnNames, String[] columnValues) Sets the SET clause for the UPDATE command.
Object	formatValue(Column column, Object value)
String	formatValue(String columnName, String columnValue) Returns a formatted table column value of appropriate type for a database Insert or Update statement.
String	getQualifiedAlias(Table table) Returns a fully-qualified database Table alias.
Table	getTable() Returns the database table to execute the SQL command upon.
boolean	isPreparedStatement() Returns true if creating an prepared, i.e.
boolean	isStatement() Returns true if creating a static SQL statement.
void	logNoRequiredClause(String command, String objectName, String clauseKeyword) Logs an error message for required SQL (DML) statement clause.
static void	main(String[] args) Executes unit tests for the SQLHelper class.
String	removeDoubleQuotes(String sqlString) Removes double quotes from SQL string, if present.
void	setPreparedStatement(boolean preparedStatement) Sets the prepared SQL statement flag.
void	setTable(Table table) Sets the database table to execute the SQL command upon.

Methods inherited from class java.lang.Object

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

Field Detail

COMMA

public static final String COMMA

The SQL statement comma character.

See Also:

Constant Field Values

EQUALS

public static final String EQUALS

The SQL statement equals character.

See Also:

Constant Field Values

LEFT_PARENTHESIS

protected static final String LEFT_PARENTHESIS

The SQL statement left parenthesis character.

See Also:

Constant Field Values

NULL

public static final String NULL

The SQL statement null keyword.

See Also:

Constant Field Values

RIGHT_PARENTHESIS

protected static final String RIGHT_PARENTHESIS

The SQL statement right parenthesis character.

See Also:

Constant Field Values

SPACE

public static final String SPACE

The SQL statement space character.

See Also:

Constant Field Values

SUBSTITUTION_VALUE

protected static final String SUBSTITUTION_VALUE

The SQL statement substitution value character.

See Also:

Constant Field Values

Constructor Detail

SQLHelper

public SQLHelper()

Constructs a new SQLHelper object.

Method Detail

formatValue

public Object formatValue(Column column,
                          Object value)

getQualifiedAlias

public String getQualifiedAlias(Table table)

Returns a fully-qualified database Table alias.

Returns:

A fully-qualified database Table alias.

See Also:

Into

addCommas

public String addCommas(String[] sqlClauseItems)

Adds commas to SQL list items and return a comma-delimited SQL clause.

Returns:

String The comma-delimited SQL clause.

addDoubleQuotes

public String addDoubleQuotes(String sqlString)

Adds double quotes to the SQL string, if the SQL string is not already contained in double quotes.

Returns:

String The SQL string with double quotes.

removeDoubleQuotes

public String removeDoubleQuotes(String sqlString)

Removes double quotes from SQL string, if present.

Returns:

String The SQL string without double quotes.

addParentheses

public String addParentheses(String sqlString)

Adds parentheses to an SQL clause, if the SQL clause is not already contained in parentheses.

Returns:

String The SQL clause with parentheses.

addSingleQuotes

public String addSingleQuotes(String sqlString)

Adds single quotes to the SQL string, if the SQL string is not already contained in single quotes.

Returns:

String The SQL string with single quotes.

createNameValues

public String createNameValues(String[] columnNames,
                               String[] columnValues)

Sets the SET clause for the UPDATE command. A VALUES clause specifies the table column values for each table column.

Returns:

Update This Update statement object.

formatValue

public String formatValue(String columnName,
                          String columnValue)

Returns a formatted table column value of appropriate type for a database Insert or Update statement.

Returns:

String The insert/update table column value.

getTable

public Table getTable()

Returns the database table to execute the SQL command upon.

Returns:

Table The database table.

isPreparedStatement

public boolean isPreparedStatement()

Returns true if creating an prepared, i.e. precompiled, SQL statement.

Returns:

boolean

isStatement

public boolean isStatement()

Returns true if creating a static SQL statement.

Returns:

boolean

logNoRequiredClause

public void logNoRequiredClause(String command,
                                String objectName,
                                String clauseKeyword)

Logs an error message for required SQL (DML) statement clause.

setPreparedStatement

public void setPreparedStatement(boolean preparedStatement)

Sets the prepared SQL statement flag.

setTable

public void setTable(Table table)

Sets the database table to execute the SQL command upon.

main

public static void main(String[] args)

Executes unit tests for the SQLHelper class.