uk.ac.ed.epcc.webapp.jdbc

Interface SQLContext

All Superinterfaces:

Contexed

All Known Implementing Classes:

MysqlSQLContext, PostgresqlSQLContext

public interface SQLContext
extends Contexed

This encodes the differences between different databases and dialects of SQL.

Method Summary

Modifier and Type	Method and Description
void	close() Clean up internal state
DateSQLExpression	convertToDate(SQLExpression<? extends java.lang.Number> val, long res) Convert a Number SQLExpression to a date.
SQLExpression<? extends java.lang.Number>	convertToMilliseconds(SQLExpression<java.util.Date> expr) Convert a Date SQLExpression to milliseconds
default SQLExpression<? extends java.lang.Number>	convertToSeconds(SQLExpression<java.util.Date> expr)
default SQLExpression<? extends java.lang.Number>	dateDifference(long resolution, SQLExpression<java.util.Date> start, SQLExpression<java.util.Date> end) generate a SQLExpression for the difference between two dates.
java.sql.Connection	getConnection() Get a database connection for the current context
java.lang.String	getConnectionHost() Get an identifying string for the database host we are connected to.
FieldTypeVisitor	getCreateVisitor(java.lang.StringBuilder sb, java.util.List<java.lang.Object> args) Get a FieldTypeVisitor used to generate table specifications.
DatabaseService	getService() get the DatabaseService
SQLExpression<java.lang.String>	hashFunction(Hash h, SQLExpression<java.lang.String> arg) Generate a SQL hash function.
boolean	isReadOnly() Is this a read-only connection
java.lang.StringBuilder	quote(java.lang.StringBuilder sb, java.lang.String name) Quote a field or table name
java.lang.StringBuilder	quoteQualified(java.lang.StringBuilder sb, java.lang.String table, java.lang.String name) Quote a field or table name

Methods inherited from interface uk.ac.ed.epcc.webapp.Contexed

getContext

Method Detail

getConnection

java.sql.Connection getConnection()

Get a database connection for the current context

Returns:

quote

java.lang.StringBuilder quote(java.lang.StringBuilder sb,
                              java.lang.String name)

Quote a field or table name

Parameters:

sb - StringBuilder

name -

Returns:

modified StringBuilder

quoteQualified

java.lang.StringBuilder quoteQualified(java.lang.StringBuilder sb,
                                       java.lang.String table,
                                       java.lang.String name)

Quote a field or table name

Parameters:

sb - StringBuilder

table -

name -

Returns:

modified StringBuilder

convertToMilliseconds

SQLExpression<? extends java.lang.Number> convertToMilliseconds(SQLExpression<java.util.Date> expr)

Convert a Date SQLExpression to milliseconds

Parameters:

expr -

Returns:

SQLExpression

convertToSeconds

default SQLExpression<? extends java.lang.Number> convertToSeconds(SQLExpression<java.util.Date> expr)

dateDifference

default SQLExpression<? extends java.lang.Number> dateDifference(long resolution,
                                                                 SQLExpression<java.util.Date> start,
                                                                 SQLExpression<java.util.Date> end)

generate a SQLExpression for the difference between two dates.

Parameters:

resolution - size of time unit (in milliseconds)

start -

end -

Returns:

SQLExpression

convertToDate

DateSQLExpression convertToDate(SQLExpression<? extends java.lang.Number> val,
                                long res)

Convert a Number SQLExpression to a date.

Parameters:

val -

res - resolution in milliseconds

Returns:

SQLExpression

hashFunction

SQLExpression<java.lang.String> hashFunction(Hash h,
                                             SQLExpression<java.lang.String> arg)
                                      throws CannotUseSQLException

Generate a SQL hash function.

Parameters:

h - Hash algorithm to apply

arg - SQLExpression to hash

Returns:

SQLExpression

Throws:

CannotUseSQLException

getCreateVisitor

FieldTypeVisitor getCreateVisitor(java.lang.StringBuilder sb,
                                  java.util.List<java.lang.Object> args)

Get a FieldTypeVisitor used to generate table specifications.

Parameters:

sb - StringBuilder to add SQL fragments to

args - List query parameters

Returns:

FieldTypeVisitor

getConnectionHost

java.lang.String getConnectionHost()

Get an identifying string for the database host we are connected to.

Returns:

close

void close()
    throws java.lang.Exception

Clean up internal state

Throws:

java.lang.Exception

getService

DatabaseService getService()

get the DatabaseService

Returns:

isReadOnly

boolean isReadOnly()

Is this a read-only connection

Returns:

Throws:

DataException