com.edustructures.sifworks.tools.queries
Class QueryFormatter

java.lang.Object
  com.edustructures.sifworks.tools.queries.QueryFormatter

Direct Known Subclasses:

SQLQueryFormatter

public abstract class QueryFormatter
extends java.lang.Object

The abstract base class for query formatters, which format SIF_Query queries in another form such as an SQL WHERE clause. The way in which a query is formatted is determined by the subclass implementation. A subclass must implement these methods:

• getOpenBrace
• getCloseBrace
• getOperator
• renderField
• renderValue

Version:

ADK 1.0

Constructor Summary

QueryFormatter()
Constructs a QueryFormatter

Method Summary

java.lang.String	format(Query query, java.util.Map table) Builds a query string given a dictionary of field definitions and a Query instance.
java.lang.String	format(Query query, java.util.Map table, boolean explicit)
abstract java.lang.String	getCloseBrace() Return the text that should be inserted for a closing brace
abstract java.lang.String	getOpenBrace() Return the text that should be inserted for an opening brace
abstract java.lang.String	getOperator(ComparisonOperators op) Return the text that should be inserted for the particular comparison operator, such as "Equals"
abstract java.lang.String	getOperator(GroupOperators op) Return the text that should be inserted for the particular grouping operator, such as "AND"
abstract java.lang.String	renderField(ElementDef field, java.lang.Object def) Return the text for a field name
abstract java.lang.String	renderValue(java.lang.String value, java.lang.Object def) Return the text for a field value

Methods inherited from class java.lang.Object

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

Constructor Detail

QueryFormatter

public QueryFormatter()

Constructs a QueryFormatter

Method Detail

format

public java.lang.String format(Query query,
                               java.util.Map table)
                        throws QueryFormatterException

Builds a query string given a dictionary of field definitions and a Query instance. This method evaluates the conditions of that Query to produce a textual query string in the format determined by the implementation.

The dictionary should contain application-defined field values that map to ElementDef key elements. Whenever a SIF element or attribute is found in the Query, the corresponding application-defined field is used in its place.

A special convention allows agents to define an in-line translation table for replacing SIF element/attribute values with values defined in the table. If a field is expressed in the form "field-name{value1=cons1;value2=cons2;..}", the comma-delimited list of values within the curly braces is applied to the value of the SIF_Value element in the SIF_Query, such that "value1" is represented as "cons1". For example, the acceptable values for LibraryPatronStatus/@SifRefIdType attribute are "StudentPersonal" and "StaffPersonal". If in your application you represent these values as numeric types - say, 1 and 2, respectively - you could create the following in-line translation table to instruct the QueryFormatter to substitute "StudentPersonal" with "1" and "StaffPersonal" with "2": "CircRecord.PatronType{StudentPersonal=1;StaffPersonal=2}"

Parameters:

query - An ADK Query object, usually obtained during the processing of a SIF_Request by a Publisher message handler

table - A dictionary that maps SIFDTD ElementDef constants to application-defined field values

Throws:

QueryFormatterException

format

public java.lang.String format(Query query,
                               java.util.Map table,
                               boolean explicit)
                        throws QueryFormatterException

Throws:

QueryFormatterException

getOpenBrace

public abstract java.lang.String getOpenBrace()

Return the text that should be inserted for an opening brace

getCloseBrace

public abstract java.lang.String getCloseBrace()

Return the text that should be inserted for a closing brace

getOperator

public abstract java.lang.String getOperator(ComparisonOperators op)

Return the text that should be inserted for the particular comparison operator, such as "Equals"

getOperator

public abstract java.lang.String getOperator(GroupOperators op)

Return the text that should be inserted for the particular grouping operator, such as "AND"

renderField

public abstract java.lang.String renderField(ElementDef field,
                                             java.lang.Object def)
                                      throws QueryFormatterException

Return the text for a field name

Parameters:

field - The field name

def - The corresponding field definition from the Map passed to the format method

Returns:

The implementation returns the field name in whatever form is appropriate to the implementation, using the supplied def Object if necessary to obtain additional field information.

Throws:

QueryFormatterException

renderValue

public abstract java.lang.String renderValue(java.lang.String value,
                                             java.lang.Object def)
                                      throws QueryFormatterException

Return the text for a field value

Parameters:

field - The field value

def - The corresponding field definition from the Map passed to the format method

Returns:

The implementation returns the field value in whatever form is appropriate to the implementation, using the supplied def Object if necessary to obtain additional field information

Throws:

QueryFormatterException